Femap Commands

December 13, 2017 | Author: MSC Nastran Beginner | Category: Windows Vista, Microsoft Windows, System Software, Technology, Computing
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FEMAP Commands

Version 10.3

Proprietary and Restricted Rights Notice This software and related documentation are proprietary to Siemens Product Lifecycle Management Software Inc. © 2011 Siemens Product Lifecycle Management Software Inc. All Rights Reserved. Siemens and the Siemens logo are registered trademarks of Siemens AG. NX is a trademark or registered trademark of Siemens Product Lifecycle Management Software Inc. or its subsidiaries in the United States and in other countries. All other trademarks, registered trademarks or service marks belong to their respective holders.

Siemens PLM Web:

http://www.femap.com

Customer Support Phone: Web:

(714) 952-5444, (800) 955-0000 (In US & Canada) http://support.ugs.com

The following copyright refers only to the “bmp2raster.exe” executable distributed with FEMAP: NeuQuant Neural-Net Quantization Algorithm Copyright (c) 1994 Anthony Dekker NEUQUANT Neural-Net quantization algorithm by Anthony Dekker, 1994. See "Kohonen neural networks for optimal colour quantization" in "Network: Computation in Neural Systems" Vol. 5 (1994) pp 351-367 for a discussion of the algorithm. See also http://members.ozemail.com.au/~dekker/NEUQUANT.HTML Any party obtaining a copy of these files from the author, directly or indirectly, is granted, free of charge, a full and unrestricted irrevocable, world-wide, paid up, royalty-free, nonexclusive right and license to deal in this software and documentation files (the "Software"), including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons who receive copies from any such party to do so, with the only requirement being that this copyright notice remain intact.

Conventions This manual uses different fonts to highlight command names or input that you must type.

a:setup

Shows text that you should type.

OK, Cancel

Shows a command name or text that you will see in a dialog box.

Throughout this manual, you will see references to Windows. Windows refers to Microsoft® Windows XP, Windows Vista, and Windows 7 (32-bit and 64-bit versions). You will need one of these operating environments to run FEMAP for the PC. This manual assumes that you are familiar with the general use of the operating environment. If you are not, you can refer to the Windows User’s Guide for additional assistance. Similarly, throughout the manual all references to FEMAP, refer to the latest version of our software.

Table of Contents

1

Proprietary and Restricted Rights Notice 1 Table of Contents 1. Introduction 2. File Manipulation 2.1 Opening a Model File . . . 2.1.1 File, New... . . . . 2.1.2 File, Open... . . . . 2.1.3 File, Close... . . . . 2.1.4 File, Close All . . . 2.2 Saving the Model File . . . 2.2.1 File, Save... . . . . 2.2.2 File, Save As... . . . 2.2.3 File, Save All . . . 2.2.4 File, Timed Save... . . 2.3 Importing/Exporting Files. . . 2.3.1 File, Import Menu . . . 2.3.2 File, Export Menu . . . 2.3.3 File, Analyze... . . . 2.4 Using Notes and References . . 2.4.1 File, Notes... . . . . 2.4.2 File, References... . . . 2.5 Using Print, Copy, and Paste . . 2.5.1 File, Page Setup... . . . 2.5.2 File, Print... . . . . 2.5.3 File, Printer Setup . . . 2.5.4 File, Picture . . . . 2.5.5 File, Messages Menu . . 2.6 Using Rebuild and Preferences. . 2.6.1 File, Rebuild... . . . 2.6.2 File, Preferences . . . 2.7 Using File, Recent Models - 1,2,3,4 . 2.8 Exiting FEMAP . . . .

3. Geometry

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3.1 Creating Points . . . . . . 3.1.1 Geometry, Point... . . . . 3.2 Creating Curves . . . . . 3.2.1 Lines . . . . . . 3.2.2 Arcs . . . . . . 3.2.3 Circles . . . . . . 3.2.4 Splines . . . . . . 3.2.5 Curves from Surfaces . . . 3.3 Creating Surfaces . . . . . 3.3.1 Sketch . . . . . . 3.3.2 Boundary Surfaces... . . . 3.3.3 Surfaces . . . . . . 3.3.4 Midsurface . . . . . 3.4 Creating Solids/Volumes . . . . 3.4.1 Volumes . . . . . . 3.4.2 Solids . . . . . . 3.5 Copying Geometry . . . . . 3.5.1 Geometry, Copy Commands . . 3.5.2 Geometry, Radial Copy Commands 3.5.3 Geometry, Scale Commands . . 3.5.4 Geometry, Rotate Commands . 3.5.5 Geometry, Reflect Commands .

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. 2-1 . 2-1 . 2-1 . 2-2 . 2-2 . 2-2 . 2-2 . 2-3 . 2-3 . 2-3 . 2-3 . 2-3 . 2-6 . 2-8 . 2-8 . 2-8 . 2-8 .2-10 .2-10 .2-12 .2-15 .2-15 .2-19 .2-20 .2-20 .2-20 .2-49 .2-49

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. 3-1 . 3-1 . 3-1 . 3-1 . 3-8 .3-11 .3-15 .3-19 .3-27 .3-28 .3-28 .3-32 .3-41 .3-43 .3-43 .3-47 .3-61 .3-61 .3-62 .3-63 .3-63 .3-64

TOC-2

Table of Contents

3.6 Modifying Geometry . . . . . . . . 3.6.1 Curve Operations . . . . . . . 3.6.2 Moving Geometry . . . . . . . 3.6.3 Edit/Parameters . . . . . . . . 3.6.4 Advanced Updates - Modify, Update Other Commands 3.7 Deleting Geometry . . . . . . . .

4. Finite Element Modeling

4.1 Creating Coordinate Systems . . . . 4.1.1 Model, Coord Sys... . . . . . 4.2 Creating Finite Element Entities . . . . 4.2.1 Model, Node... . . . . . . 4.2.2 Model, Element... . . . . . 4.2.3 Model, Material . . . . . 4.2.4 Model, Property... . . . . . 4.2.5 Model, Layup... . . . . . . 4.3 Creating Loads And Constraints . . . . 4.3.1 Create/Activate Load Set . . . . 4.3.2 Load Definitions . . . . . 4.3.3 Finite Element Loads . . . . . 4.3.4 Geometric Loads . . . . . 4.3.5 Load Analysis Options . . . . 4.3.6 Load Set Manipulation . . . . 4.3.7 Activate/Create Constraint Set . . . 4.3.8 Constraint Definitions . . . . 4.3.9 Finite Element (Nodal) Constraints . . 4.3.10 Geometric Constraints . . . . 4.3.11 Constraint Set Manipulation . . . 4.4 Creating Connections and Regions . . . 4.4.1 Connect, Automatic... . . . . 4.4.2 Connect, Surfaces... . . . . . 4.4.3 Connect, Connection Property... . . 4.4.4 Connect, Connection Region... . . . 4.4.5 Connect, Connector... (Contact Pair) . 4.4.6 Connect, Fluid Region... . . . . 4.4.7 Connect, Bolt Region... . . . . 4.4.8 Connect, Rotor Region... . . . . 4.5 Creating Aeroelastic Entities . . . . 4.5.1 Model, Aeroelasticity, Panel/Body... . 4.5.2 Model, Aeroelasticity, Property... . . 4.5.3 Model, Aeroelasticity, Spline... . . 4.5.4 Model, Aeroelasticity, Control Surface... . 4.6 Using Optimization Analysis . . . . 4.6.1 Goal . . . . . . . . 4.6.2 Vary - Design Variables . . . . 4.6.3 Limit - Design Constraints. . . . 4.7 Working with Functions . . . . . 4.8 Modifying FEA Entities . . . . . 4.8.1 Moving FEA Entities . . . . . 4.8.2 Edit/Parameters . . . . . . 4.8.3 Advanced Updates . . . . . 4.9 Deleting FEA Entities . . . . . . 4.10 Preparing for Analysis . . . . . 4.10.1 Defining a Analysis Set . . . . 4.10.2 Running the Analysis with an Analysis Set

5. Meshing

5.1 Meshing on Geometry . . . 5.1.1 Mesh, Geometry Preparation 5.1.2 Mesh, Mesh Control . . 5.1.3 Mesh, Geometry. . . 5.2 Non-Geometry Meshing . . 5.2.1 Mesh, Between... . . 5.2.2 Mesh, Region... . . . 5.2.3 Mesh, Connection . . 5.2.4 Mesh, Transition... . .

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3-64 3-64 3-70 3-76 3-78 3-79

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4-1 4-1 4-3 4-3 4-4 4-15 4-26 4-43 4-49 4-49 4-50 4-52 4-62 4-69 4-75 4-79 4-80 4-81 4-83 4-85 4-87 4-87 4-89 4-90 4-110 4-113 4-114 4-116 4-117 4-118 4-118 4-122 4-124 4-127 4-129 4-129 4-129 4-130 4-130 4-133 4-133 4-141 4-145 4-154 4-157 4-159 4-163

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5-1 5-1 5-6 5-22 5-45 5-45 5-50 5-51 5-53

TOC-3

Table of Contents

5.3 Modifying a Mesh . . . . . . 5.3.1 Mesh, Editing Menu . . . . 5.3.2 Mesh, Remesh Menu . . . . 5.3.3 Mesh, Edge Members... . . . 5.3.4 Mesh, Smooth... . . . . . 5.4 Copying a Mesh . . . . . . 5.4.1 Mesh, Copy Menu . . . . . 5.4.2 Mesh, Radial Copy Menu . . . 5.4.3 Mesh, Scale Menu . . . . . 5.4.4 Mesh, Rotate Menu . . . . 5.4.5 Mesh, Reflect Menu . . . . 5.5 Meshing by Extruding, Revolving, and Sweeping 5.5.1 Mesh, Extrude Menu . . . . 5.5.2 Mesh, Revolve Menu . . . . 5.5.3 Mesh, Sweep . . . . . .

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6.1 View Activation, Management, and Options . . 6.1.1 View, Create/Manage... . . . . . 6.1.2 View, All Views... . . . . . . 6.1.3 View, Background... . . . . . 6.1.4 View, Visibility... . . . . . . 6.1.5 View, Select and View, Options . . . 6.1.6 View, Advanced Post . . . . . 6.2 Modifying the View . . . . . . . 6.2.1 View, Rotate Menu . . . . . 6.2.2 View, Align By Menu . . . . . 6.2.3 View, Autoscale . . . . . . 6.2.4 View, Magnify... . . . . . . 6.2.5 View, Zoom... . . . . . . 6.2.6 View, UnZoom... . . . . . . 6.2.7 View, Center... . . . . . . 6.2.8 View, Pan... . . . . . . . 6.2.9 Deleting Views (Delete, View command) . 6.3 Window Menu Commands . . . . . 6.3.1 Manipulating Multiple View Windows . . 6.3.2 Redrawing Windows . . . . . 6.4 Groups and Layers . . . . . . . 6.4.1 Differences Between Groups and Layers . 6.4.2 Layer Commands . . . . . . 6.4.3 Group Menu Commands . . . . 6.4.4 Deleting Groups (Delete, Group command). 6.4.5 Renumbering Groups . . . . .

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. 6-1 . 6-1 . 6-2 . 6-2 . 6-5 .6-13 .6-32 .6-33 .6-33 .6-39 .6-39 .6-40 .6-41 .6-42 .6-43 .6-43 .6-44 .6-45 .6-45 .6-48 .6-50 .6-51 .6-51 .6-52 .6-71 .6-71

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. 7-1 . 7-1 . 7-2 . 7-5 . 7-7 .7-24 .7-49 .7-67 .7-69 .7-89 .7-90 .7-97 7-101 7-113 7-115 7-116 7-116 7-140 7-141 7-142 7-144

6. Viewing Your Model

7. Modeling Tools

7.1 Undo and Workplane . . . . . 7.1.1 Undo and Redo . . . . . 7.1.2 Tools, Workplane... . . . . 7.2 Dockable Panes. . . . . . . 7.2.1 Tools, Model Info . . . . . 7.2.2 Tools, Meshing Toolbox . . . 7.2.3 Tools, PostProcessing Toolbox . . 7.2.4 Tools, Entity Editor . . . . 7.2.5 Tools, Data Surface Editor . . . 7.2.6 Tools, Entity Info . . . . . 7.2.7 Tools, Data Table . . . . . 7.2.8 Tools, Programming, API Programming 7.2.9 Tools, Programming, Program File . 7.2.10 Tools, Other Windows, Messages . 7.2.11 Tools, Other Windows, Status Bar . 7.3 Tools, Toolbars... . . . . . . 7.3.1 Standard Toolbars . . . . . 7.4 Other FEMAP Tools. . . . . . 7.4.1 Tools, Parameters... . . . . 7.4.2 Tools, Convert Units... . . . . 7.4.3 Entity Tools . . . . . .

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TOC-4

Table of Contents

7.4.4 Measuring Tools . . 7.4.5 Checking Tools . . . 7.4.6 Tools, Stress Wizard . . 7.5 List Menu Commands . . . 7.5.1 List, Tools Menu . . 7.5.2 List, Geometry Menu. . 7.5.3 List, Surface... . . . 7.5.4 List, Connection Menu . 7.5.5 List, Model Menu . . 7.5.6 List, Output Menu . . 7.5.7 List, Group... . . . 7.5.8 List, View... . . . 7.5.9 List, Model Info . . . 7.5.10 List, Destination... . . 7.6 Model Style (View, Select command) 7.6.1 Features . . . . 7.6.2 Hidden Line Modes . . 7.6.3 Free Edge . . . . 7.6.4 Free Face . . . .

8. Post-Processing

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8.1 Procedure . . . . . . . . . 8.1.1 Reading Results . . . . . . . 8.1.2 Selecting Views . . . . . . . 8.1.3 Changing Options (View Options) . . . 8.1.4 Manipulating/Listing Output . . . . 8.2 Types of Views - View Select... . . . . . 8.2.1 Selecting Data for a Model Style . . . 8.2.2 Choosing Deformed and Contour Styles . . 8.2.3 Choosing an XY Style . . . . . 8.3 View Options - PostProcessing . . . . . 8.3.1 Post Titles... . . . . . . . 8.3.2 Deformed Style . . . . . . . 8.3.3 Vector Style . . . . . . . 8.3.4 Animated Style . . . . . . . 8.3.5 Deformed Model... . . . . . . 8.3.6 Undeformed Model.... . . . . . 8.3.7 Trace Style... . . . . . . . 8.3.8 Contour Type... . . . . . . . 8.3.9 Contour/Criteria Style... . . . . . 8.3.10 Contour/Criteria Levels... . . . . 8.3.11 Contour/Criteria Legend... . . . . 8.3.12 Criteria Limits . . . . . . . 8.3.13 Criteria - Elements that Pass/Fail... . . . 8.3.14 Beam Diagram... . . . . . . 8.3.15 IsoSurface... . . . . . . . 8.3.16 IsoLine... . . . . . . . . 8.3.17 Streamline... . . . . . . . 8.3.18 Contour Vector Style... . . . . . 8.3.19 XY Titles... . . . . . . . 8.3.20 XY Legend... . . . . . . . 8.3.21 XY Axes Style... . . . . . . 8.3.22 XY X Range/Grid... . . . . . . 8.3.23 XY Y Range/Grid... . . . . . . 8.3.24 XY Curve 1 through XY Curve 9... . . . 8.3.25 Freebody options . . . . . . 8.4 Specialized Post-processing . . . . . . 8.4.1 View, Advanced Post, Contour Model Data... . 8.4.2 View, Advanced Post, Animation... . . . 8.4.3 View, Advanced Post, Dynamic Cutting Plane... 8.4.4 View, Advanced Post, Dynamic IsoSurface... . 8.4.5 View, Advanced Post, Dynamic Streamline... . 8.4.6 View, Advanced Post, Beam Cross Section... . 8.5 Output Manipulation . . . . . . . 8.5.1 Model, Output, Create Manage/Set... . . 8.5.2 Model, Output, Vector... . . . . .

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7-147 7-152 7-166 7-169 7-169 7-170 7-173 7-175 7-176 7-186 7-187 7-188 7-189 7-189 7-190 7-190 7-190 7-190 7-190

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Table of Contents

8.5.3 Model, Output, Define... . . . . . . 8.5.4 Model, Output, Fill... . . . . . . . 8.5.5 Model, Output, Process . . . . . . . 8.5.6 Model, Output, Calculate... . . . . . . 8.5.7 Model, Output, From Load... . . . . . 8.5.8 Model, Output, Transform... . . . . . . 8.5.9 Model, Output, Extrapolate... . . . . . 8.5.10 Model, Output, Global Ply... . . . . . 8.5.11 Model, Output, Convert Complex... . . . . 8.5.12 Model, Output, Expand Complex... . . . . 8.5.13 Model, Output, Forced Response... . . . . 8.6 Listing Output (List, Output Menu) . . . . . . 8.6.1 List, Output, Query... . . . . . . . 8.6.2 List, Output, Compare... . . . . . . 8.6.3 List, Output, Summary to Data Table.... . . . 8.6.4 List, Output, Results to Data Table... . . . . 8.6.5 List, Output, Nodal Changes to Data Table... . . 8.6.6 List, Output, Unformatted... . . . . . . 8.6.7 List, Output, Standard... . . . . . . 8.6.8 List, Output, Use Format... . . . . . . 8.6.9 List, Output, Force Balance . . . . . . 8.6.10 List, Output, Force Balance to Data Table . . . 8.6.11 List, Output, Force Balance Interface Load. . . 8.6.12 List, Output, Force Balance Interface Load to Data Table 8.6.13 List, Output, XY Plot... . . . . . . 8.6.14 List, Output, Format... . . . . . . . 8.7 Deleting Output (Delete, Output Menu) . . . . . 8.7.1 Delete, Output, All... . . . . . . . 8.7.2 Delete, Output, Set... . . . . . . . 8.7.3 Delete, Output, Vector... . . . . . . 8.7.4 Delete, Output, Entry... . . . . . . . 8.7.5 Delete, Output, Format... . . . . . .

9. Help and Non-Menu

9.1 Help Menu Commands . . 9.1.1 Help Topics . . . 9.1.2 Help, Toolbars... . . 9.1.3 Help, Dockable Panes... 9.1.4 Help, NX Nastran . . 9.1.5 Help, Analysis . . 9.1.6 Help, What’s New . . 9.1.7 Help, Examples . . 9.1.8 Help, Using Help... . 9.1.9 Help, Programming . 9.1.10 Help, Basic Language . 9.1.11 Help, Tip of the Day . 9.1.12 Help, FEMAP on the Web 9.1.13 Help, Technical Support 9.1.14 Help, About... . . 9.2 Non-Menu Commands . . 9.2.1 Previous Command... . 9.2.2 Dialog Function Keys .

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TOC-6

Table of Contents

1.

Introduction FEMAP is finite element modeling and post-processing software that allows you to perform engineering analyses both quickly and confidently. FEMAP provides the capability to develop sophisticated analyses of stress, temperature, and dynamic performance directly on the desktop. With easy access to CAD and office automation tools, productivity is dramatically improved compared to traditional approaches. FEMAP automatically provides the integration that is necessary to link all aspects of your analysis. FEMAP can be used to create geometry, or you can import CAD geometry. FEMAP provides powerful tools for meshing geometry, as well as applying loads and boundary conditions. You may then use FEMAP to export an input file to over 20 finite element codes. FEMAP can also read the results from the solver program. Once results are obtained in FEMAP, a wide variety of tools are available for visualizing and reporting on your results.

Geometry FEMAP can directly import geometry from your CAD or design system. In fact, FEMAP can directly import a solid model from any ACIS-based or Parasolid-based modeling package. If your modeling package does not use either of these geometry engines, you can use the FEMAP IGES or STEP reader. If you are using I-DEAS, you can bring a single part into FEMAP by exporting a Viewer XML (IDI) file from I-DEAS. These files can be read and then stitched together to form a solid. This typically requires using one command. If you do not have CAD geometry, you can create geometry directly in FEMAP using powerful wireframe and solid modeling tools. Solid modeling directly in FEMAP uses the robust Parasolid modeling engine. You can build or modify solid models using the Parasolid engine, and then export the geometry out of FEMAP. This is very convenient if you need to export geometry to CAD packages that are Parasolid-based.

Finite Element Modeling Regardless of the origin of your geometry, you can use FEMAP to create a complete finite element model. Meshes can be created by many methods ranging from manual creation, to mapped meshing between keypoints, to fully automatic meshing of curves, surfaces and solids. FEMAP can even work with your existing analysis models. You can import and manipulate these models using the interfaces to any of the supported analysis programs. Appropriate materials and section properties can be created or assigned from FEMAP libraries. Many types of constraint and loading conditions can be applied to represent the design environment. You can apply loads/constraints directly on finite element entities (nodes and elements), or you can apply them to geometry. FEMAP will automatically convert geometric conditions to nodal/elemental values upon translation to your solver program. You may even convert these loads before translation to convince yourself that the loading conditions are appropriate for your model.

Checking Your Model At every step of the modeling process, you receive graphical verification of your progress. You need not worry about making a mistake because FEMAP contains a multi-level undo and redo capability. FEMAP also provides extensive tools for checking your model before you analyze it to give you the confidence that you have properly modeled your part. It constantly examines input to prevent errors in the model, and provides immediate visual feedback. FEMAP also provides a comprehensive set of tools to evaluate your finite element model and identify errors that are often not obvious. For example, FEMAP can check for coincident geometry, find improper connections, estimate mass and inertia, evaluate your constraint conditions, and sum your loading conditions. Each of these methods can be used to identify and eliminate potential errors, saving you considerable time and money.

Analyzing Your Model When your model is complete, FEMAP provides interface to over 20 popular programs to perform finite element analysis. You can even import a model from one analysis program and automatically convert it to the format for a different analysis program.

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Introduction

The NX Nastran for FEMAP solver is a general finite element analysis program for structural and thermal analysis that is integrated with FEMAP.

Post-processing After your analysis, FEMAP provides both powerful visualization tools that enable you to quickly interpret results, and numerical tools to search, report, and perform further calculations using these results. Deformation plots, contour plots, animations, and XY plots are just some of the post-processing tools available to the FEMAP user. FEMAP supports OpenGL, which provides even more capability for post-processing, including dynamic visualization of contours through solid parts. You can dynamically rotate solid contoured models with one push of your mouse button. Section cuts and isosurfaces can be viewed dynamically by simply moving your cursor.

Documenting Results Documentation is also a very important factor with any analysis. FEMAP obviously provides direct, high quality printing and plotting of both graphics and text. Frequently, however, graphics or text must be incorporated into a larger report or presentation. FEMAP can export both graphics and text to non-engineering programs with a simple Windows Cut command. You can easily export pictures to popular programs such as Microsoft Word, Microsoft Power Point, and Adobe Framemaker. You can export to spreadsheets, databases, word processors, desktop publishing software, and paint and illustration programs. These links enable you to create and publish a complete report or presentation, all electronically, right on your desktop. With support for AVI files, you can even include an animation directly in your Power Point Presentation or Word document. FEMAP also supports VRML and JPEG format so anyone can easily view results with standard viewers.

FEMAP Documentation FEMAP comes with a set of three printed manuals: FEMAP Examples, the FEMAP User Guide, and the FEMAP Commands reference manual. The FEMAP online help includes the contents of these manuals, as well as several additional books. The complete set includes: •

FEMAP Examples: Step-by-step examples for new users.



FEMAP User Guide: General information on how to use FEMAP, including an overview of the finite element modeling process. Also contains reference information for the FEMAP analysis program and geometry interfaces.



FEMAP Commands: Detailed information on how to use FEMAP commands.



FEMAP API Reference: Information on how to write your own applications that work with FEMAP.



What’s New: New features for this release.

When NX Nastran for FEMAP is installed, online help includes all of the above, as well as a full set of current NX Nastran documentation, to assist you during the solving portion of the analysis process.

2. File Manipulation This topic describes the File menu commands. These commands work with new or existing FEMAP models. They can produce printed or plotted hard copy, and transfer both text and graphics to other Windows and analysis programs. The commands on the File menu are described in the following sections: •

Section 2.1, "Opening a Model File"



Section 2.2, "Saving the Model File"



Section 2.3, "Importing/Exporting Files"



Section 2.4, "Using Notes and References"



Section 2.5, "Using Print, Copy, and Paste"



Section 2.6, "Using Rebuild and Preferences"



Section 2.7, "Using File, Recent Models - 1,2,3,4"



Section 2.8, "Exiting FEMAP"

2.1 Opening a Model File This section contains three commands, File, New, which opens a new FEMAP model file, File, Open, which allows you to access an existing FEMAP model file, and File, Close, which allows you to close any active model. The FEMAP model file is a binary database of everything contained in the FEMAP file. You can have multiple model files open in a given FEMAP session. All three commands are discussed further below. Note: If you are having a problem opening a file, check to confirm that the file has only one extension. Files with two extensions may have difficulty being opened due to the Windows file structures and default parameters. Also, you may want to remove any spaces in the file name. Spaces are typically not a problem, but may cause difficulty on certain file systems.

2.1.1 File, New... ... starts a new, empty model. All new models are named “Untitled”. When you save a model, FEMAP will prompt you give the model a name. (For information on how to save your current model, see Section 2.2, "Saving the Model File".) The FEMAP main window title bar will change to show the model name once saved. When you start FEMAP without specifying a model file name on the command line or the “?” command line option, you begin with a new, empty model. This is just like using the File, New command.

2.1.2 File, Open...

Shift+F4

... accesses an existing FEMAP model. File, Open uses the standard file access dialog box to request the file name of the model you wish to use. The default file name extension is *.MODFEM. Legacy *.MOD files may also be opened. Multiple FEMAP models can be open in the same FEMAP session. Click the title tabs at the top of the graphics window to switch between open models and views. The title bar for the FEMAP main window shows the file name of your active model. When you open a model, it returns to the screen with the same graphics windows active (and in the same position) as when you saved the file. When multiple views are open in one model, the view names will appear on title tabs above the FEMAP graphics window. When multiple models are open, the title tabs will show the file name of the model and the view name in the following format, File Name.modfem : View Name.

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Finite Element Modeling

If you start FEMAP and specify a model file name on the command line, FEMAP will open that model just as if you opened the file using this command. You can also start FEMAP using the “?” command line option. This will display the standard file access dialog box just like File, Open. You can also open an existing FEMAP model by “dragging and dropping” a FEMAP model file (*.MODFEM or *.MOD file) from an existing directory window onto an open FEMAP interface. If the model is from the current FEMAP version, it will simply open the model. If the model is from an older version, FEMAP will alert you and ask if it OK to import a FEMAP neutral file. (See Section 2.3.1.4, "File, Import, FEMAP Neutral..." for more details on the FEMAP neutral file).

2.1.3 File, Close... ... allows you to close the model file that is currently active in FEMAP. If only one model is open, File, Close will close the model, but FEMAP will remain running without a model until a new model is started using File, New, an existing model is opened using File, Open, or FEMAP is shut down using File, Exit. When multiple models are open, this command will only close the active model and the associated views, leaving the other open models running for continued use. FEMAP will always prompt you to save your model when the last open view is being closed.

2.1.4 File, Close All ... closes all currently open models in your FEMAP session with one command. Only available when multiple models are open in the same FEMAP session. FEMAP will prompt you to save each model individually when this command is used.

2.2 Saving the Model File FEMAP also has four commands which allow you to save the FEMAP binary database (model file). They are: •

File, Save, which saves the file under the existing name,



File, Save As, which allows you to change the model filename,



File, Save All, which saves all the open files under their existing names,



File, Timed Save, which allows periodic saving of the model file automatically.

2.2.1 File, Save...

F4

... writes a copy of your active model to the permanent file you specify. If your active model is “Untitled”, this command asks for a filename by calling File, Save As. You must specify a file name, or you cannot save an “Untitled” model. Whenever you are working on an active named model, File, Save simply writes to the same model file - without prompting for a file name. Your model will be named if you open an existing model file, or if you had previously saved the model. If you want to write to a different file, use File, Save As.

When to Save When you work on a FEMAP model, all changes are retained in memory, and in a temporary disk file. Your original model will not be updated until you save the data. This can be a mixed blessing. If you make a mistake, you can simply use File, Open to revert to your original model file. You will be right back to where you did your last save. On the other hand, if you accidentally turn your computer off, or forget to save your changes, they WILL be lost. In general, you should save whenever you make a significant change to your model and you are certain the change is correct. It usually does not take long to save the model, and the benefits can be well worth the time. Alternatively, you can use the File, Timed Save command to save your model automatically, at a time interval that you specify.

File, Save As...

2-3

2.2.2 File, Save As... ... is identical to File, Save, except that it always displays the standard file access dialog box to ask for the name of the file to write. File, Save automatically calls File, Save As if you are working on an “Untitled” model. You should only use this command when you want to save your model with a different file name.

2.2.3 File, Save All ... saves all currently open models in your FEMAP session with one command. Only available when multiple models are open in the same FEMAP session. FEMAP saves the models in the order in which they were open, so the first model opened will be the first model saved and so on.

2.2.4 File, Timed Save... ... instructs FEMAP to save all open models automatically either at a specified time interval or after a number of commands have been performed. It allows you to turn timed save on or off and set the time between automatic saves. The default settings for this option can be set in File, Preferences, Database. You also can request FEMAP to notify you prior to automatically saving your open models. If you choose this option, you can skip a timed save by canceling FEMAP's notification. Even if you cancel, however, timed save is still active and will notify you again when the interval expires. To disable timed save, you must turn it off with File, Timed Save. If you are working with an 'Untitled' model, you must specify a file name before the model can be saved. This follows the normal process, just like the File, Save As command. If your open models are not named, they will be saved to specified file names. Unlike some other programs, FEMAP does not interrupt your commands to save your open models. After the interval has expired, FEMAP waits until the end of your next command to save your open models. This means that FEMAP will never automatically save your open models unless you are actively working on a specific model. If you are not accessing any FEMAP commands, Timed Save will be inactive; however, the timer will continue to run. In many cases, you will find that Timed Save will save your open models after the next command that you access.

2.3 Importing/Exporting Files The next menu commands under the File command allow you to both import and export data. FEMAP works as a general pre and post-processor for finite element analysis. You may also import and export geometry, as well as analyze your model if you have loaded one for the many solver programs that can be automatically executed by FEMAP. The commands under this area of the menu are explained more fully below.

2.3.1 File, Import Menu The File, Import commands enable you to import information from CAD packages as well as other FEA codes. There are four commands based upon the type of information to import. You can import geometry from CAD packages, the analysis model from other FEA codes, the results from FEA solver codes, or a FEMAP neutral file. Each command is further explained below.

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Finite Element Modeling

2.3.1.1 File, Import, Geometry... ... is the interface between FEMAP and other CAD programs. When you select this command, you will see the standard Windows file section dialog box. There are many types of geometry files which FEMAP can import: •

ACIS Solid Model Files - *.SAT files (up to version 16)



Parasolid Solid Model Files - *.X_T files (up to version 20)



IGES Files - *.IGS files (4.0 to 5.3)



STEP Files - *.STP files (AP203 and AP214 geometry)



Stereolithography Files - *.STL files



Wireframe Files - *.DXF files.



CATIA V4 Models - *.MDL files (version 4.1.9 to 4.2.4)



CATIA V4 Express Files - *.EXP, *.DLV files



CATIA V5 Files - *.CATP files (up to CATIA V5 Version 18)



I-DEAS Files - *.IDI files



Pro/ENGINEER Models - *.PRT and *.ASM files (versions 16 to Wildfire 4.0)



Solid Edge Models - *.PAR, *.PSM, *PWD, and *ASM files (up to Solid Edge with Synchronous Technology)



Unigraphics Models - *.PRT files (versions 11 to 18 and NX 1 - NX 6)

In each of these cases, simply select the file to import. Normally FEMAP will display all of the files that it knows how to read, using the most common file name extensions for these formats. If your file uses a different extension, you may rename it, or simply drop down the file type list, choose the appropriate format, then specify the file name. If you do not use the standard extensions for each of the formats, and you are use the default All Geometry type, FEMAP may choose the wrong format to read the file, which will result in errors. Depending upon the type of file you choose, FEMAP may display information in the Messages window and then prompt you with one or more additional dialog boxes where you can set various options. For more information on the options contained in the dialog boxes, see Section 9, "Geometry Interfaces" in the FEMAP User Guide. You can also import some types of geometry into FEMAP by “dragging and dropping” a geometry file of a currently supported format (*.X_T; *.SAT; *.IGES or *.IGS; and *.STEP or *.STP only) from an existing directory window onto an open FEMAP interface. FEMAP will bring up a dialog box asking you if it is “OK to Start New Model” with “dragged and dropped” geometry or if you would like to “Add” the geometry “to Current Model”. Click Yes to create a new model or No to add it to the current model.

File, Import, Analysis Model...

2.3.1.2 File, Import, Analysis Model...

2-5

Ctrl+Shift+T This command allows you to import an analysis model from many popular FEA codes. FEMAP has support for over 20 finite element solvers. By default, FEMAP will only show certain interfaces for solvers whose translators are currently being maintained. Once you select this command, you will see the Import From dialog box. Note:

All import options can be made visible by going to File, Preferences..., choosing the Interfaces tab and turning on the Enable Old Analysis Interfaces option. This is not recommended as the translators for the solvers not listed by default are no longer maintained and the FEMAP may no longer read some required entities.

Simply select the appropriate code, and FEMAP will then prompt you for the name of the input file. You may be asked other questions based upon the format you have chosen. For a more details, see Section 7, "Translation Tables for Analysis Programs" and Section 8, "Analysis Program Interfaces" in the FEMAP User Guide. You can also import analysis models from some solvers into FEMAP by “dragging and dropping” an analysis file of a currently supported format from an existing directory window onto an open FEMAP interface. Currently supported analysis input files “drag and drop” include *.DAT and *.NAS for NASTRAN programs; *.INP for ABAQUS; and *.ANS for ANSYS. All of these file types can be read in for the version of the solver currently supported by the FEMAP translators. (For a more details, see Section 7, "Translation Tables for Analysis Programs" and Section 8, "Analysis Program Interfaces" in the FEMAP User Guide.) FEMAP will bring up a dialog box asking you if it is “OK to Start New Model” with “dragged and dropped” analysis input file or if you would like to “Add” the input file “to Current Model”. Click Yes to create a new model or No to add it to the current model.

2.3.1.3 File, Import, Analysis Results... ... allows you to read results from an analysis you have performed, so you can then use FEMAP’s powerful postprocessing capability. When you choose this command, you will see the same dialog box as the File, Import, Analysis Model. Simply select the appropriate format and then enter the file name. For more information on the individual solver codes supported, see Section 7, "Translation Tables for Analysis Programs" and Section 8, "Analysis Program Interfaces" in the FEMAP User Guide. Note:

As with File, Import, Analysis Model, all import options can be made visible by going to File, Preferences..., choosing the Interfaces tab and turning on the Enable Old Analysis Interfaces option. This is not recommended as the translators for the solvers not listed by default are no longer maintained and the FEMAP may no longer read some required entities.

You can also import analysis results from some solvers into FEMAP by “dragging and dropping” an results file of a currently supported format from an existing directory window onto an open FEMAP interface. Currently supported analysis results files for “drag and drop” include *.OP2, *.F06, and *.XDB for NASTRAN programs; *.FIL for ABAQUS; and *.RST for ANSYS. All of these file types can be read in for the version of the solver currently supported by the FEMAP translators. (For a more details, see Section 7, "Translation Tables for Analysis Programs" and Section 8, "Analysis Program Interfaces" in the FEMAP User Guide.) After the file is “dropped” onto the FEMAP interface, FEMAP will bring up all dialog boxes which would normally appear when importing analysis results from a certain solver with the exception of the Import Results From

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Finite Element Modeling

dialog box. FEMAP is able to skip the Import Results From dialog box because it has recognized which solver the results file has come from already Note:

You should always import analysis results into an existing model containing those nodes and elements. If you read information for entities that do not exist in your model, FEMAP will provide a warning. This could mean that you have read the results into the wrong (or modified) model.

2.3.1.4 File, Import, FEMAP Neutral... ... translates a FEMAP neutral file into a binary FEMAP database file. Once the FEMAP neutral file is read, you can save this file as a FEMAP *.modfem file. Because the FEMAP neutral file is compatible across all platforms, it is the recommended format for long term storage. For more information on the FEMAP neutral file, see Section 8.1.2, "Reading a FEMAP Neutral File" in the FEMAP User Guide. You can also import a FEMAP neutral file into FEMAP by “dragging and dropping” a neutral file (*.NEU) from an existing directory window onto an open FEMAP interface. The FEMAP neutral file MUST have been created with either the current release or a previous release of FEMAP for import to be successful. FEMAP will bring up a dialog box asking you if it is "OK to Start New Model" with "dragged and dropped" neutral file or if you would like to "Add" the entities "to Current Model". Click Yes to create a new model or No to add it to the current model. There are also options to Read individual parts of the neutral file instead of the whole thing. The individual parts are Geometry Model, Analysis Model, Output, Groups, and Views.

2.3.2 File, Export Menu The File, Export menu allows you to export geometry, analysis model, or a FEMAP neutral file. Each of these areas are described below.

2.3.2.1 File, Export, Geometry... ...provides export capability for FEMAP solid models. FEMAP currently supports various types of geometry export. •

ACIS Solid Model Files - *.SAT files



Parasolid Solid Model Files - *.X_T files



STEP Files - *.STP



IGES Files - *.IGS



Stereolithography Files - *.STL files



VRML Files

The ACIS SAT interface will take geometry inside FEMAP and generate a .SAT file using an Parasolid to ACIS converter. The STEP interface will allow you to export a Parasolid entity to a STEP AP203 solid via a conversion from the Parasolid modeling kernel into the STEP standard. Similarly, the IGES interface will allow you to export Parasolid geometry to an IGES file. The stereolithography file is only applicable for a meshed model. FEMAP will export a faceted representation of your model using the FEA mesh as the basis of this file. The final option, VRML, allows easy viewing of solid or meshed models in many standard viewing programs. You can even save a deformed, contour plot in VRML format.

File, Export, Analysis Model...

2.3.2.2 File, Export, Analysis Model...

2-7

Ctrl+T

This command is used to start the translation to a analysis input file for a selected solver. FEMAP will display the Export Method dialog box which allows the user to translate using a Analysis Set or translate using the manual method, specifying the analysis parameters each time the active model is translated. •

Activate Analysis Set: The list box will contain any previously created Analysis Sets. If a Analysis Set has already been activated then that set will automatically be selected. Once you choose the Analysis Set you wish to translate from, press the OK button to create the input file.



Create/Edit Set: If you have not previously created a Analysis Set, pressing this button will bring you to the Model, Analysis command so that you can create or edit a existing Analysis Set. See Section 4.10, "Preparing for Analysis" and Section 4.10.1, "Defining a Analysis Set"

Note:



The preferred method of exporting an analysis model is to use the Analysis Set Manager. Support for new features or expanded solver support will only be added to the Analysis Set Manager. For solvers supported by the Analysis Manager see: Section 4.10, "Preparing for Analysis" When you create an Analysis Set all the options necessary for solving are defined once and saved with the model or in a library. This enables the user to reuse the Analysis Sets and for FEMAP to create the input file without user interaction

Other Interfaces: Pressing this button will bring up the Export To dialog box. When you select this command, you will see the available analysis programs for export include the FEMAP Neutral file, SINDA/G, CAEFEM, PATRAN, I-DEAS, and CommaSeparated file. Simply select the appropriate format. Unlike File, Import, Analysis Model, however, you will need to select the appropriate analysis type (Static, Normal Modes/Eigenvalue, etc.), when required. These are the only programs FEMAP can export a file to unless the “Enable Old Analysis Interfaces” option is checked on the Interfaces tab of the Preferences dialog box.

Note:

To translate using the “old method” of specifying the analysis parameters by prompting you to fill in the necessary options (for ALL supported solvers) you must use File, Preferences..., choose the Interfaces tab and turn on the Enable Old Analysis Interfaces option. With this option turned on, the Export To dialog box from FEMAP versions 9.1 and before will appear. This is not recommended as the translators for ALL solvers (including Nastran, ANSYS, and ABAQUS) using the “old method” are no longer maintained and any option added to or fixed in a translator after FEMAP version 8.0 will likely not be included in the input file generated.

For a more complete description of the options available for each analysis program, see Section 8, "Analysis Program Interfaces" in the FEMAP User Guide.

2.3.2.3 File, Export, FEMAP Neutral... ... allows you to store the FEMAP model file as a neutral file. Because the FEMAP neutral file is compatible across all platforms, it is the recommended format for long term storage. For more information on the FEMAP neutral file, see Section 8.1.1, "Writing a FEMAP Neutral File" in the FEMAP User Guide.

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Finite Element Modeling

2.3.3 File, Analyze... File, Analyze works similarly to File, Export, Analysis Model except if a Analysis Set is active then femap will simply write the model and try to launch the solver without user input. If an Analysis Set is not Active then the Export Model dialog box will be displayed so that the user can create an Analysis Set or translate using the Manual method by pressing the Manually Create Analysis Model button. If Manual creation of the input file is used then FEMAP will determine the analysis program and analysis type from the settings that you chose in File, Preferences, Interfaces. In the cases where FEMAP can run the analysis program, this command will also optionally begin the analysis.

2.4 Using Notes and References 2.4.1 File, Notes... The File, Notes command provides a method of attaching notes to your model as well as translate lines to your model input file. When you select this command, the Model Notes and Text for Translation dialog box will appear. This command is most often used to provide identifying characteristics to your model, such as date, program, creator etc. You may also provide information for translation by selecting the Translation Text option. You can choose to include the translation text in an output file by selecting the Include During Write Translation option. When these commands are selected, FEMAP will automatically write this information to the heading area (i.e. where FEMAP automatically writes its own date/time information) of your active model. Note:

Be careful when using the Translation Text option. The information included in the Notes area must have the appropriate syntax for the type of translation you are performing. FEMAP will not perform any checks on this syntax. It will simply write the information as you input it; therefore, improper syntax could cause a fatal error in your analysis run.

2.4.2 File, References... The File, References command allows you to insure that you are using the most current version of certain entities in a given model. A single model can contain references for any number of imported files (Geometry, analysis models, and analysis results sets). References can be added or removed manually or FEMAP can be set up to create them automatically based on settings in the File Reference Options in the Interface Preferences dialog box (See Section 2.6.2.7, "Interfaces").

File, References...

2-9

If FEMAP is generating references automatically, they will appear after the geometry, analysis model, or analysis results have been imported and reference a path to a particular file. FEMAP uses the “time stamp” on the file to determine if the reference is up to date or not. A check mark in a green circle will appear if the date of a reference file has not changed. When the date of a file that is being referenced has been changed, a “x” in a red circle will appear next to the reference.

There are a few methods to bring a reference up to date: Read File - Allows you to read in the updated file from the location currently specified in the reference. Note:

Depending on the type of geometry file that was referenced (.x_t, .sat, .igs, .stp, etc.) and the extent the geometry was changed can have a substantial effect on the usability of the mesh and any geometrybased loads and boundary conditions that are currently in the model. Be sure to verify all loads and boundary conditions in the model are correctly applied after new geometry file has been read into FEMAP. The same can be said about analysis models and results files as node and element numbering, loads and boundary conditions can also change and cause continuity issues.

Update Reference - Allows you to manually bring a reference up to the current date. This allows to continue to use the model without being alerted that the reference is not up to date, even though you did not read the new file in to FEMAP. A check mark in a yellow circle will appear next to the reference after the date has been updated. If the file is changed again after the Update Reference command has been used, FEMAP will again alert you that the reference is no longer valid. You can then make the decision to use the Read File command or simply update the reference once again. Locate File - If the reference file has moved to a different directory, this command allows you to browse and specify the path to the moved file in order to update the reference. Remove All - Allows you to remove all references from the list at once and FEMAP will no longer check any references for that model. Remove Reference - Allows you to remove a reference from the list and FEMAP will no longer check to make sure that this reference is up to date. Add Reference - Allows you to manually add a reference to the FEMAP model for geometry, analysis models, and analysis results sets.

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2.5 Using Print, Copy, and Paste The commands under this section of the menu involve exporting information to a printer, or to documentation programs for reporting. FEMAP is a true Windows program, which greatly simplifies the transfer of data from FEMAP to other Windows programs such as Microsoft PowerPoint or Word. The commands in this section involve different methods of transferring this data to programs such as Microsoft Word, or to a printer. Each of the five commands available in this section are explained more fully below.

2.5.1 File, Page Setup...

Shift+F3

... specifies headers, footers, margins, position and other parameters. These items will be used when printing/plotting either text or graphics using the File, Print command. The sections of the Page Setup dialog box include:

Page Header and Footer The Header and Footer text are printed in the top and bottom margin of every page. This text uses the Default Fixed Pitch Font for the selected printer/plotter. You can specify any other font by selecting Other Font, and then specifying the typeface and point size that you want to use. Note:

If you are using True Type, or other scalable fonts, you will often see only one size in the Point Size list, and it will usually be a very large: 50 point or larger. Since the font is scalable, you can choose any size that you want; you just have to type it manually.

Other Printed Text FEMAP uses these options when you print listings (with the List, Destination command). They are never used for printing/plotting graphics nor for printing the Messages and other text windows. Just like headers and footers, this text uses the Default Fixed Pitch Font. Again, you can select any other available font. Hint:

If the display looks fine on the screen, but characters are improperly printed, it is likely that your Windows printer driver does not support the selected font. Simply change the font both in this dialog box as well as under View Options, Label, Entities, and Colors, Label Parameters to a supported font.

Hint:

FEMAP listings will not be as easy to read if you select a proportionally spaced font. Selecting a fixed pitch font will properly align all columns in the listing.

File, Page Setup...

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Page Margins These margins identify the distance from the four edges of the page where you want printing to occur. When you are printing listings, printing will start at the top-left margin. The bottom and right margins will be used to compute the line length and number of lines on the page. For graphics printing, FEMAP combines the margins with the options in Plot Position and Size to compute the actual size and position of the graphics image. Often printers and plotters cannot print closer than some minimum distance from the edge of the paper. Check your printer documentation for information on these minimum values. Setting a margin smaller than those minimums can result in FEMAP trying to print to an inaccessible region of the paper. This should not cause any unrecoverable problems, but you will not see the portion of the print that is in the inaccessible regions.

Plot and Metafile Style The four options in this group allow you to control some specific details regarding the appearance of a graphics plot. FEMAP uses these options when you print a graphic image using File Print, or place an image from an XY Plot in a Metafile the File, Picture, Copy command. When Draw Border is active, a single line border will be drawn around the image. The location of this border is equivalent to the on-screen window border. In FEMAP's default configuration, graphic windows have black or shaded backgrounds, with white or colored images. In many cases, you may want to retain the white background of the paper and print with black lines - even though it does not match the image on the screen. In Render Mode, FEMAP will swap the black or shaded background to white and change any white entities to black, when a window is printed. When in Non-Render mode, setting Swap Black and White will automatically reverse the black and white colors during your print, resulting in the print style described. This option has no effect on other colors, which will always be printed as shown on the screen. This option also controls color swapping for Metafiles that you transfer to the Clipboard using File, Picture, Copy. If you are printing to a black and white printer like a laser printer, you may find that certain colors that are displayed on the screen do not show up very well (or at all) when you print them. This is caused by the method Windows uses to shade colors on the monochrome printer. To overcome this problem, you can change all your model colors to black and white so they can print well, or just turn on the Monochrome switch. In this case, colors will still be displayed on the screen, but all colors (except color 0, which is black) will be converted to white when they are printed. You can combine Monochrome with the Swap Black and White setting to print all black lines on a white background. While the Monochrome option can quickly make a print look much better, it must be used with caution. Since it sets all colors but background to a single color, it can result in a picture which is totally illegible. For example, you should never use it if you are using a color other than color 0 for the background. If you try, nothing will be visible. Similarly, any plot with filled areas is not usually a good candidate for Monochrome. Contour plots, which rely heavily on color shading, will not work well. Setting Transparent Background will simply skip plotting the background. For printing on white paper, you will still want to use Swap Black and White. Otherwise, you will get white lines on your white paper! Transparent Background is most often used when creating a Metafile of an XY Plot to be transferred into another application. Here, you may want just the graphic image, and rely on the other application to supply the background. This creates an image that can be overlaid on top of other text/graphics without erasing them.

Plot Position and Size These options control the shape, size and position of a graphics image that you print. Choosing Maintain Window Aspect Ratio will force the height-to-width ratio of a printed image to match the shape of the screen or window that you print. If you choose this option, the resulting print will be the largest possible rectangle, with the specified height-to-width ratio that fits inside the margins and size options that you specify. Choosing this option will generally result in a smaller printed image, but one that more closely resembles what you see on the screen. Integer Scaling is a further limitation to the mapping of the screen image to the printed page. When this option is on, the pixels in the on-screen window are scaled by the largest integer (whole number) scale factor that fits inside the margins and size specifications. Scaling occurs both horizontally and vertically. If the option is off, the scale factor used is a real number (whole + fractional number) that exactly fits the margin and size specifications. Setting this option usually results in a smaller printed image. When printing using bitmap formats however, you should always specify this option for the best quality print. If you do not, FEMAP stretches the bitmap (by the fractional portion of the real scale factor) to fit the margins. The stretching operation results in distortions that degrade the appearance of the image.

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Fill Printer Margins and Custom Size control the size of a printed graphic image. Choosing Fill Printer Margins simply calculates the printable area by subtracting the margins from the size of the paper. Custom Size allows you to specify the height and width that you want. Always make sure that you specify a size that is smaller than the margins that you choose. No matter which size option you pick, the print may still be reduced from that size if you selected either Maintain Window Aspect Ratio or Integer Scaling. The final option sets (Top, T/B Center, Bottom, Left, L/R Center or Right) control the position of the printed image within the margins. If you choose to fill the margins (and none of the other options reduce the image size) your choice here will not matter: FEMAP fills the margins. Whenever the image does not fill the margins however, these options control the alignment. For example, choosing Top and Left will result in an image that has its top and left borders aligned with the top and left margins. By combining these alignment options with the margins, you can position an image anywhere on the page.

Reset and Permanent Permanent allows you to save your Page Setup options, so that they will be the defaults for all future models and sessions. Reset deletes the saved options, and returns you to the normal FEMAP defaults.

2.5.2 File, Print...

F3

This command produces a printed or plotted hardcopy of your model. Header

Footer

The Print dialog box allows you to choose what will be printed and in what format. You will see two command buttons, Page Setup and Printer Setup, which provide you with further control of printing parameters. These buttons simply invoke the File, Page Setup and File, Printer Setup commands, respectively.

Print to File This button allows you to print directly to a file rather than to your printer. It can be used to create files in a native printer format (for example, Postscript). When you press OK, an additional dialog box will ask you for the name of the file that you want to create. Printed Image

Image Orientation

Header and Footer

These options provide a quick way to set the headers and footers that will be placed at the top and bottom of the page. They can also be set via the File, Page Setup command. In fact, you must use Page, Setup if you want to change fonts or other options.

Page Preview This section of the dialog box shows a symbolic graphical representation of your printed page. It quickly lets you know if your page and printer setup options are correct. You do not need to waste a piece of paper, or the time required to make a print. The outer black border represents the paper on which you will print. FEMAP calculates the size and orientation of this boundary (and the paper) from your Windows printer configuration. You can change these settings using Printer Setup. Inside this border you will see four lines (Top, Bottom, Right and Left) that represent relative margin positions. You also may see shorter horizontal lines located inside the top and bottom margins. These lines represent the locations where the page headers and footers (specified in Page Setup) will be printed. They are only visible if the header and/or footer is not blank. Finally, located inside the margin lines, is a filled rectangle. This rectangle represents the size and position of your printed image. If the printed image is smaller than you expected, FEMAP may have auto-

File, Print...

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matically reduced the size due to your Page Setup choices. Maintain Window Aspect Ratio and Integer Scaling are especially important.

What to Print These options specify what will be printed or plotted. •

Selecting Active View will print a picture of your model as it currently appears in your graphics window. If you currently have multiple graphics windows open (from one or multiple models), only the “top-most” (the one that you last selected in the active model) window will be printed.



If you do have multiple windows, and want to print them all as they are positioned on your screen, choose the Layout option.



Choosing Desktop will print an image of the “FEMAP Desktop” - the gray area underneath the Graphics window. This includes all windows: the Graphics window, dialog boxes, even non-FEMAP windows. This option is only available if you choose the Screen option in the Resolution section. Hint:



FEMAP can only print a multi-window layout as it is arranged on the screen with the Layout or Desktop options. Best results are usually obtained with Layout if you turn off the graphics window title bars. Otherwise, you will see gaps between the printed windows that represent the areas occupied by the title bars. In Layout mode, the Page Preview diagram shows one overall rectangle that surrounds all of your windows. Individual windows are not shown. For even more printing flexibility, you can transfer FEMAP graphics to other Windows programs which will allow you to print other page layouts.

Other print options allow you to print text/messages that are in the Messages, Program File, Entity Info, or API Program Dockable Panes. If you do not want to print all of the text in one of these Panes, you can select the lines that will be printed. For instructions, see Section 2.5.5, "File, Messages Menu". When you are printing messages, the Resolution setting and the shape of the active graphics window do not matter. When you choose this option, you will see the printed image disappear from the Page Preview area. Don’t worry; this is normal behavior, because the position of the printed messages is just based on the margin settings. Hint:



You can also print messages by using the File, Messages, Copy command and copying them to another Windows application, or by setting the List, Destination to your printer and then using any of the list commands.

Using the Data Table option will print out all of the rows that currently appear in the Data Table. When the Data Table is printed out, all of the columns for the rows will also be printed out. Since the columns in the Data Table will often be wider than the screen (or a sheet of paper), FEMAP will print out as many columns as it can for the current rows, then continue with the next set of columns for those rows directly below the first set of columns. This will continue until all of the columns for all of the current rows have been printed. To make the printed tables easier to read, the “ID” of the entities will appear as the first column in the printed table.

The print out will look like this: ID

Prop ID

Type

Topology

Orientation Node

Orientation Vector

1

1..Angle Stiffener

BEAM

Line2

0

0., 1., 0.

97

2..Upper Wing Skin

PLATE

Quad4

ID

Color

Layer

Formulation

C1

C2

1

124

1

0

6

322

97

124

1

0

6

322

C3

C4

197

7

Resolution You have three choices for the print resolution mode: Printer, Screen, or Scaled Screen.

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Finite Element Modeling



When you select Printer resolution, FEMAP recomputes the image at the resolution of the printer. The resulting printed image is almost always of much higher quality, but can take significantly longer for complex images.



Screen resolution directs FEMAP to use the on-screen bitmap and copy it to paper. The bitmap will be scaled and stretched, as required, to fill the desired margins and print size. However, the resolution of the screen image determines the ultimate print quality. This option may not be available for some older printers.



Scaled Screen resolution is much the same as Screen resolution, except the resolution is scaled by a factor which is specified using the File, Preferences command, choosing the Views tab, then pressing the Resolution button. The resolution may be scaled up (using any value above 1.0) or scaled down (using any value between 0.0 and 1.0), but typically it is not a good idea to scale the resolution down.

See Section 2.6.2.2, "Views" for more information about setting the Print Resolution scale factor.

Orientation You have two choices for the orientation of the printed image: portrait and landscape. •

Portrait positions the selected images or text in the center of a piece of paper with the longer length going from top to bottom.



Landscape positions the selected images or text in the center of a piece of paper with the longer length going from left to right.

Options •

Copies - If your printer/plotter supports making multiple copies, you can use this option to request the number of copies you need. If you choose multiple copies, and your printer does not support this option, you will receive a warning. Then, you will only get one copy of your print. For many printers, you can set this feature permanently using the Setup option under Printer Setup.

Note: •

FEMAP can only print a bitmap in render mode. FEMAP performs operations to provide more detail than the standard bitmap export, but it still may not be as clear and sharp as a Windows Metafile.

Print to File - Creates a print file (.prt file) which can then be used later and sent to a local printer.

Printing Tips Review the following items for some additional hints on printing: •

Use the Page Setup and Printer Setup options on this dialog box instead of the commands on the File menu. They graphically show the results of your settings in the Page Preview diagram.



If you want a quick draft hardcopy, print using Screen or Scaled Screen resolution. For final, high-quality output, always use Printer resolution.



When you are printing the active view using Screen resolution, you will get a better quality (higher resolution) print if you enlarge the window. Choose the Maximize button in the Window title bar to enlarge it to full-screen size prior to choosing File, Print.



Printing high-resolution images (especially color images) takes a lot of memory and/or disk space. You will need to make sure that your TEMP environment variable specifies a disk with plenty of room if you are going to print large models. Windows writes temporary files to this disk as it is printing. These files can often require many megabytes.



You cannot print when the active window is animating.



If you are having printing problems, make sure you have recent printer drivers and all windows updates.



If you want to print a contour plot on a monochrome printer, you may want to adjust the contour palette before printing. In particular, choose the View Options command. Then select the Post-processing category and the Contour/Criteria Levels option. Press Set Levels..., then press Reset Gray. Choose OK twice to accept the grayscale contour palette. With the grayscale palette loaded, your prints should come out much cleaner. If you are having trouble distinguishing contour levels on the print, you can adjust the individual colors in the palette. One good approach is to change every other color so that it uses a cross-hatched color instead of a solid color. This will result in contours that alternate between solid and the various hatch patterns.

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2.5.3 File, Printer Setup This command directly sets and modifies printer-related options. It also displays a list of the active printers. Printers that you installed, but did not activate, will not be shown. To choose a printer for use in FEMAP, select it from the list. To change the setup for the printer you have selected, press Setup. Depending on the printer, you will see one or more additional dialog boxes. These let you establish options like the active printing mode (i.e., 75, 150 or 300 dots/inch), portrait or landscape paper orientation, fonts, colors and many more. The dialog boxes that you see when you choose Setup are not really part of FEMAP. They are part of the printer driver that you loaded when you installed the printer for Windows. You also can modify all of the same settings using the Windows Control Panel. Refer to the Windows documentation and the documentation for your printer for further advice on setting options for particular printers. Using Control Panel, you can also install or activate additional printers. You can even make changes while FEMAP is still running. The next time you choose the Print or Printer Setup command, it will recognize any control panel changes that you have made. When you change certain printer settings, like the paper orientation (landscape vs. portrait) or paper size, it is usually good to review the Page Setup options. This will give you the opportunity to make any changes to margins, plot sizes or positions that are appropriate for your new printer settings.

2.5.4 File, Picture The commands on this submenu let you transfer a copy of your graphics to the Windows clipboard and then to other applications, or to a file. You can also redisplay graphics files.

2.5.4.1 File, Picture, Copy...

Ctrl+Shift+C

... transfers a copy of the image in the active graphics window to the Windows clipboard. No additional input is required. By default, FEMAP transfers the image in Bitmap and Windows Device Dependent Bitmap (DDB) formats. By producing these formats, you have great flexibility when you transfer the image to many other software packages. Note:

Ctrl+C can be used as a general copy command. FEMAP takes into account which window or dockable pane is currently active. When the main graphics window is active, Ctrl+C will perform the File, Picture, Copy command.

When you transfer a device independent bitmap to the clipboard, the black and white colors can be swapped. This is useful for changing a picture with white lines on a black background into black lines on a white background. The Swap Black and White option, in the File, Page Setup command, controls color swapping. If this option is on, FEMAP will swap the colors. The File, Page Setup, Monochrome option can also be used to convert to a monochrome image. These options have no effect on regular device dependent bitmaps which are copied to the clipboard. Additional Page Setup options control the background for Metafiles. The File, Picture, Copy command will be disabled if the current window is animating. You cannot transfer animations to the clipboard.

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Transferring Graphics to Other Applications After you use File, Picture, Copy to load your graphics to the clipboard, simply switch to the application that you want to receive the image. For most Windows applications that accept graphics input from the clipboard, you will find a Paste command somewhere in the menu (often under Edit). Pressing Ctrl+V (or Shift+Ins) will usually invoke that command, or you can simply choose it from the menu. The Paste command should immediately load the image into the other application. Some applications (like Windows Paint) sometimes require you to choose Paste twice. Other applications require you to define a region or area where the graphics will be placed prior to pasting. Refer to the documentation for the receiving application for more information.

2.5.4.2 File, Picture, Copy Layout... ... is the same as File, Picture, Copy, except that instead of simply saving the active graphics window, this command transfers a copy of all views currently visible in the “graphics area” of the active instance of FEMAP to the Windows clipboard. No additional input is required. By default, FEMAP transfers the image in Palette, Windows Device Dependent Bitmap (DDB), and Windows Metafile or Picture formats.

2.5.4.3 File, Picture, Copy Desktop... ...is the same as File, Picture, Copy, except that instead of simply saving the active graphics window, this command saves the entire screen to the Windows clipboard. No additional input is required. By default, FEMAP transfers the image in Palette, Windows Device Dependent Bitmap (DDB), and Windows Metafile or Picture formats.

2.5.4.4 File, Picture, Save...

Ctrl+F3

... transfers a copy of the image in the active graphics window to a file. The standard file access dialog box allows you to specify the name of the file to create. In addition to the normal fields in the file access dialog, there are more options that specify the picture format: •

Bitmap



Bitmap Series



Video for Windows - AVI



GIF



Animated GIF



JPEG



TIFF



PNG



Metafile (GDI Graphics Only - No Longer Available)



Placeable MF (Metafile) (GDI Graphics Only - No Longer Available)

All formats are not available for all types of pictures.

Using Bitmaps If you select Bitmap, which is available for all views, the default file extension is .BMP, and the file will be saved as a Windows Device Independent Bitmap. Bitmap files contain only the array of pixels currently displayed in the window and are therefore equivalent to the size of the window. When you choose this format, FEMAP will ask if you want to compress the bitmap. Compressed bitmaps usually take up significantly less disk space, but are incompatible with some Windows programs. Check the documentation for your other applications, or try transferring a compressed bitmap to see if your other applications can support it. If you only plan to replay your bitmaps using FEMAP, you should always use the compressed format.

Using GIFs There are several options available when saving a GIF or Animated GIF file. These may be set in the Views tab of the FEMAP Preferences by pressing the GIF Options button. For more information, see the GIF Options Button portion of Section 2.6.2.2, "Views" under File, Preferences.

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Using Metafiles (Obsolete for File, Picture, Save) If you select either Metafile or Placeable MF, the default file extension is .WMF. Both options save the picture as a Metafile. Metafile chooses the Windows Metafile format, while Placeable MF chooses the Placeable Metafile Format that is used by many Windows applications. Most often you will want to use the placeable Metafile for more reliable transfer to other programs. Metafiles contain commands that draw graphics into the current window. For this reason, when you load a Metafile into another application, you can scale and stretch it. The Metafile will redraw itself for the new shape. If you plan to load your pictures into another Windows application, you should refer to the documentation for that application to find advice on choosing the best format for that application. The Metafile and Placeable Metafile options are not available in Render mode. Just like for the File, Picture, Copy command, the colors black and white can be swapped when you save a Metafile or device independent bitmap. You can control color swapping with the Swap Black and White option under the File, Page Setup command. FEMAP will also convert all colors to a black and white image if the Monochrome option is on.

Saving Animations If your active graphics window is animating, FEMAP will let you choose either a bitmap, bitmap series, animated GIF, or AVI format. The single bitmap animation file format is very similar to the standard bitmap format, but will be incompatible with most (if not all) Windows applications other than FEMAP. Likewise, you will not be asked to choose compression. FEMAP uses the .BMP default file extension for animation files just like for standard bitmaps. Depending on the number of animation frames, the size of your animating window and the number of colors supported by your graphics board, these files can be very large. Unlike standard bitmaps or Metafiles, the various Page Setup options do not change animations. They are always saved just as they appear on the screen. You can also save animations as a Bitmap Series: a series of static bitmaps, one per animation frame with sequentially numbered file names. This format can be used with other tools to create video (AVI) files. If you choose Bitmap Series, FEMAP will save each frame in the animation as a series of bitmaps, under the names *n.bmp, where n ranges from 0 to n-1 frames. If you want to save an animation to replay in FEMAP, you should save the entire animation as one bitmap, not a series of bitmaps. This format is strictly for programs which can play a series of bitmaps. You can also simply save the animation as a Video for Windows (AVI) file. AVI files can be imported directly into most Windows applications. Hint:

When saving an AVI file, you must have a color resolution > 256 colors. if you have 256 colors or less, you will not be able to successfully import the AVI files into other applications.

When saving an animation from FEMAP as an Animated GIF, you will have some choices to make. First, like static GIF files, you will need to choose a Color Optimization option. You may choose from Network, Octree, or Color Diffusion (Dither). Next, you may specify a Frame Delay in milliseconds. Finally, by checking the Save GIF Frame Series box, the series of GIF files used to create the Animated GIF will also be saved.

2.5.4.5 File, Picture, Save Layout... ... is the same as File, Picture, Save, except that instead of simply saving the active graphics window, this command saves all views currently visible in the “graphics area” of the active instance of FEMAP to the file you specify. As always, FEMAP uses the standard file access dialog. Unlike File, Picture, Save however, the “layout” can only be saved in bitmap, JPEG, PNG, GIF, or TIFF format.

2.5.4.6 File, Picture, Save Desktop... ... is the same as File, Picture, Save, except that instead of simply saving the active graphics window, this command saves the entire screen to the file you specify. As always, FEMAP uses the standard file access dialog. Unlike File, Picture, Save however, the desktop can only be saved in bitmap, JPEG, PNG, GIF, or TIFF format.

2.5.4.7 File, Picture, Save JT... ... saves the FEMAP Graphics window as a *.JT file (Teamcenter Visualization file). Only entities visible in the active graphics window will be saved in the JT file. As always, FEMAP uses the standard file access dialog. After JT file has been named, there are a few JT Options which can be selected for the file.

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First, select one of the automatically generated names or “Untitled” from the Name drop-down list. Another option is to type a name directly in the field. Second, choose your JT File Version. The default version is 8.1, which was the first JT version to support a contoured image. You will want to use the same version of JT or a lower version than your visualization product is currently using. Note:

A different default JT File Version may be set using the “JT File Version” option in the Views tab of File, Preferences (Section 2.6.2.2, "Views")

Third, select JT File Units by selecting a “unit of length” from the drop-down list. Any unit may be selected and the JT File will be exported using that unit for length. For example, if “Inch” is selected, anything with a length of 1 “unit” in FEMAP will be 1 inch in the JT File. FEMAP will attempt to determine the “correct unit” based on the option set for “Solid Geometry Scale Factor” on the Geometry/Model tab of File, Preferences. If using the “Other” option for “Solid Geometry Scale Factor”, FEMAP will use the entered value to determine the “correct unit”. A Hierarchal “tree control” will be created in Teamcenter Visualization depending on which options are checked. The hierarchy can also be changed by using the Move Up and Move Down buttons. Each category selected will add a level of hierarchy in the tree. You can choose how many branches will be in your tree structure by selecting different categories. There will also be several options for each category type depending on the category type that is chosen. For example, Model will have options for deformed and undeformed as well as others. Entity Type will separate Geometry into Surfaces, Curves, and Points and Finite Element Data into Nodes and Elements. Entity Subtype will add different element types to the tree such as line elements, plates, solid elements, and other element types as well as individual section cuts and isosurfaces. Layer, Property, and Material will add branches for different Layers, Properties, and Materials currently visible. Curve & Surface ID will create branches under Curve and Surface respectively for each Curve and Surface currently shown on the screen. Note:

Loads and Constraints will NOT appear in a JT file even if they are on screen when the JT file is created. They may be available in future versions of FEMAP.

Note:

Line elements which have a symbol associated with them, such as springs and gaps will be shown as a line between two positions with a “dot” on the line. Mass elements will be shown as a single “dot” and any offsets will be designated with a red line representing the offset.

2.5.4.8 File, Picture, Replay...

Alt+F3

... displays graphics that you have saved in files. Just like File, Picture, Save, you will use the standard file access dialog box to select the graphics format and file that you want to display. FEMAP will create a new window to display the bitmap image, Metafile or animation. For bitmaps, animations, and placeable Metafiles, the initial size of the replay window will be the same size as the window that you saved. If that size is too large to fit on the screen, the size will be automatically reduced. The replay window does not have a command menu, but does have a system menu. You can use the system menu, or the window borders to move and resize the window. If you resize the window, FEMAP will stretch a bitmap or scale a Metafile to fit in the new window. FEMAP adds an additional command, Original Size, to the system menu. This command will automatically return the window to its default size and position. FEMAP also adds an Animation command to the system menu. This command is identical to the View, Animation command in FEMAP. It is used to control the replayed animations. You can also stop and start replayed animations simply by clicking in the window. To stop the animation, press the left mouse button while the cursor is anywhere inside the replay window. To restart the animation, press the right mouse button. You will find that animations work

File, Messages Menu

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best if you leave the window at the original size. If you change the size, the animation will slow down dramatically since FEMAP must do many more calculations for each animation frame. If you do change the size, you can always use the Original Size command to restore the window. Note:

FEMAP will never close the replay window. You must do that manually by choosing Close from the system menu or clicking on the “X” in the upper right corner of the FEMAP Replay window. By leaving the window open, you can continue to work in FEMAP and display many simultaneous pictures just by replaying different files. The only limitation is the amount of memory available for Windows. You must be careful if you are running FEMAP or any other application maximized to the full screen. When you choose the next FEMAP command, your replay window or windows will disappear behind the maximized FEMAP window. It is very easy to forget about these extra windows. While they do no harm, they are using system resources (especially if they are animating!) that may be better applied to FEMAP or some other ongoing process. Therefore, you should always close the window as soon as you are finished looking at it.

Replaying Pictures Outside of FEMAP When you choose the File, Picture, Replay command, FEMAP actually runs a separate Windows program (REPLAY.EXE). At any time you want to view a picture, you can run that program yourself without running FEMAP. When you run REPLAY by itself, you may choose a file from the standard “File Open” dialog box. Alternatively, you can specify the full file name on the command line, for example: REPLAY PICTURE.BMP

You can also run REPLAY directly from DOS with: WIN REPLAY PICTURE.BMP

REPLAY automatically determines the type of file that you are specifying from the data in the file. It does not rely on the file name extension, so you can specify any name. The commands shown above assume that both Windows and REPLAY are in directories along your PATH. If they are not, you must add the names of the appropriate directories to these commands.

2.5.5 File, Messages Menu The commands on this submenu allow you to transfer text from the Messages window. You can copy the text to a file or to the Windows clipboard and then to other applications. By default, these commands transfer all lines of text from the Messages window to the selected file, or to the clipboard. This includes all lines of text that are visible in the window, and the lines of text that can be retrieved by scrolling. You cannot copy text that has scrolled out of FEMAP's buffer. You can set the number of lines saved in the buffer using File, Preferences, Database.

Selecting Messages If you do not want all of the text, you must select the lines that FEMAP will copy prior to invoking these commands. To select messages, point to the line that you want to select with the cursor. Press the left mouse button and drag the cursor to the last (or first) line that you want to select. As you do this, the color of the selected lines will change. Now release the button. Don't worry if some lines appear to be missed as you drag the cursor. When you release the mouse button, FEMAP will select all lines between the two points. Simply clicking on a line with the left mouse button selects just that line. Clicking anywhere in the Messages window with the right mouse button cancels any lines that you have selected. If you want to change your selection, just repeat the process. You do not have to cancel your previous selection.

2.5.5.1 File, Messages, Copy...

Ctrl+Alt+Insert

... copies the selected (or all) lines of text from the Messages window to the Windows clipboard. No additional input is required. Note:

Ctrl+C can be used as a general copy command in FEMAP. FEMAP takes into account which window or dockable pane is currently active. When the Messages pane is active, Ctrl+C will perform the File, Messages, Copy command.

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Finite Element Modeling

Remember that the Windows clipboard only holds one image or one set of text. Every time you choose this command, you automatically overwrite the previous contents of the clipboard.

2.5.5.2 File, Messages, Save... ... transfers a copy of the selected (or all) lines of text from the Messages window to a file. The standard file access dialog box allows you to specify the name of the file to create. If you select an existing file, you will be given an option to overwrite, or append to, that file. The default filename extension is *.LST.

2.6 Using Rebuild and Preferences This section of the File menu pertains to rebuilding your model file and setting default parameters (preferences) for your model files. Each of these menu commands are described further below.

2.6.1 File, Rebuild... ... verifies the integrity of your current active model and can be used to reduce the size of a model where you have deleted entities. You will be asked to choose between two levels of rebuilding. The quickest method simply checks whether all entities that are referenced by other entities exist. For example, all nodes and properties that are referenced by elements must exist. You will receive messages informing you of any missing entities. This level of rebuilding is called automatically every time you use one of the read translators to input a model. It verifies the completeness of the model that you read. The more thorough level of rebuilding (“fully rebuild”) does everything that the quick method does and also reconstructs many internal database details. If you experience a power failure while a database is being written or run out of disk space, your model file may become corrupted. This level of rebuild will recover any data that is still present. Whenever you delete entities from a FEMAP model, the space that they occupied is marked as empty. The space is still retained in the model file. When you create new entities, FEMAP will reuse this empty space before allocating any new space. Therefore, as long as you plan to add to your model, the space will not be wasted - it will be reused. If you have a shortage of disk space, or if you have done a large amount of deleting, such as deleting sets of output data, you may want to choose the full rebuild option and allow it to compress your model. This will remove all of the empty space and reduce the size of your model file. Rebuilding is not usually required, but it is non-destructive so you can use it any time you have a question about the integrity of your model. Instead of using Rebuild, you can also use the FEMAP neutral file translator to export a neutral file, and then and import it to a new FEMAP database. The new database will also be free of empty space.

2.6.2 File, Preferences

Ctrl+Shift+P

This command allows you to customize the operation of FEMAP. These options control how certain commands will operate, set defaults, and define disks or files to be used. This command bring up a “tabbed” dialog box with 10 tabs, each tab representing the type of entity you want to modify. FEMAP will remember the tab used most recently and the Preferences dialog box will open with that tab active. For more information on each individual preference tab, see Section 2.6.2.1, "Messages", Section 2.6.2.2, "Views", Section 2.6.2.3, "Render", Section 2.6.2.4, "User Interface", Section 2.6.2.5, "Database", Section 2.6.2.6, "Geometry/Model", Section 2.6.2.7, "Interfaces", Section 2.6.2.8, "Library/Startup", Section 2.6.2.9, "Color", Section 2.6.2.10, "Spaceball" Hint:

Be careful when changing preferences labeled “startup” preferences. These preferences cannot be modified for the active session, and will be saved when OK is clicked. For these settings to have any impact on how FEMAP is operating, you must close your current session of FEMAP completely. The next time you initialize FEMAP the options will be set as you selected them.

The Reset All button permanently resets all changes that you have made back to the FEMAP default configuration. You will be asked to confirm this command before FEMAP resets all options. The only preferences which will not be changed are any shortcut keys you have defined.

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2.6.2.1 Messages These options control text displayed in the Messages window. When you select the Messages tab, the Preferences dialog box will display the options for messages. These options are partitioned into two types: Max Text Lines and Fonts and Colors. Max Text Lines This option controls the maximum number of lines of text that can be retained in the Messages window. The default value is 100,000. There is no set maximum number of lines that can be set, but the higher the number of max lines, the more memory will be used and this could effect the performance of FEMAP. Max Repeated Errors Limits the number of errors of the same type which will be listed to the Messages window. Default is 100. This is useful if you have executed a command which causes the same error for each instance of a particular entity type, and you have selected a large number of entities. Set this value to “0” to have all errors listed to the Messages window, regardless of how many times it will be repeated. Message Font, Listing Font and Size Message Font chooses the font for display of messages and feedback from FEMAP. Listing Font chooses the font for display of text written to the Messages window from any listing command in FEMAP. You can choose any Message Font, Listing Font, or size that you like for text display. In general, you should always choose a fixed-pitch font. If you choose a proportionally spaced font, none of the FEMAP reports or listings will be properly aligned and they will be harder to read. Program Font and Size Program Font chooses the font for display of text which has been recorded or written in the Program File window. You can choose a size specifically for the Program Font which is independent of the Message Font and Listing Font size. Colors These options let you choose the colors of text to be displayed. You can enter a numeric color value, or choose the Palette button to select the color from the standard color palette. For these options, you must select solid colors (Colors 0 to 149). You cannot select any cross-hatching or patterned lines. You should also make sure that you do not choose a color for the background which matches any of the text colors, or you won't be able to see the text. Furthermore, you can choose to make the font Bold Face by clicking the Bold check box next to the Palette button. For best results, you should always pick a background color that results in filled areas and lines being the same color. If you do not, the background may be a different color “behind” the text than it is to the “right” of the text.

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2.6.2.2 Views When you select the Views tab, the Preferences dialog box will display the options for views. The Views tab of the Preferences dialog box is partitioned into four areas: •

Startup View (from View Library)



Picture Copy



Background Bitmaps (Render Only)



Picture Save Defaults



Options



View and Dynamic Rotation Startup View (from View Library) The Startup View area includes: •The View Number option lets you change the view that FEMAP uses when you start a new model, or when you create a new view. When this value is set to 0, FEMAP uses its normal defaults. If you want a different view, use the View Visibility dialog box to store a view in the library, then set View Number to the ID of that view as it is stored in the library. The first view in the library has an ID of 1, the second is 2, and so on. You can also use the Browse button (...) to select a view from the View library. When you start a new model, that view will be used as the default.

Picture Copy When Include Text for XY Plots option is on, FEMAP will include a table of values representing the XY Plot as text along with the picture formats when an XY Plot is copied to the clipboard. When text is included, it will be used as the default when importing into Microsoft Office applications. If you always want to paste the actual picture of the XY Plot, not the underlying data used to create the XY Plot, then this option should be “off”. Note:

If the “XY Axes Style” in the PostProcessing category of View Options is set to anything other than “0..Rectilinear”, you will get 2 sets of values. The first data pair set represents the “actual values”, the second represents “actual-log(Y-Axis)”, “log(X-Axis)-log(X-Axis)”, or “log(X-Axis)-actual” values.

When the Include Metafile Format option is on, FEMAP will send Metafile format pictures of XY Plots to the clipboard, which may then be pasted into other applications. Certain applications will paste the Metafile in by default, which may or may not be desired. If you do not want or need Metafiles, then simply uncheck this option and only bitmaps will be sent to the clipboard.

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Background Bitmaps (Render Only) The Background Bitmaps area includes two different paths which can be to specified to use bitmap images in the background of the main FEMAP graphics window (Render Mode Only): •

Background - Allows you to specify a directory path or browse directories to designate a bitmap to be used as the background of the main FEMAP graphics window. The bitmap will only be shown when either option 7..Bitmap or 8..Stretched Bitmap is chosen in the Window Background portion of the Window Background dialog box (see Section 6.1.3, "View, Background...").



Logo - Allows you to specify a directory path or browse directories to designate a bitmap to shown in a particular location in the FEMAP graphics window. The bitmap will only be shown when Show Bitmap is checked in the Logo section of Window Background dialog box (see Section 6.1.3, "View, Background...").

There are two options for resolution which will be applied to any bitmaps which have been assigned, Screen or Printer. Screen will show the bitmap on the screen the actual size of the bitmap, while Printer will show the bitmap at a size that is determined by the actual size of the bitmap multiplied by the Render Res Factor, which can be found in the Plot and Metafile Style section of the Page Setup dialog box (see Section 2.5.1, "File, Page Setup...").

Picture Save Default Format These options control set defaults file format when using the File, Picture, Save; File, Picture, Save Layout; and File, Picture, Save Desktop commands. Picture Sets the default file format when using any of the File, Picture commands, while the display is NOT animating. Choices are Bitmap (*.BMP), JPEG (*.JPG), GIF(*.GIF), PNG(*.PNG), or TIFF (*.TIF). Animation Sets default file format when using the File, Picture, Copy command, only when the display is animating. Choices are Bitmap (*.BMP), Bitmap Series (*.BMP), Video for Windows (*.AVI), or Animated GIF (*.GIF). Resolution button Allows you to set the default values for Print Resolution, Copy/Save Resolution, Pen Width, and Logo and Background Bitmap Scaling.

Print Resolution There are three options when choosing a Print Resolution. For more information see the “Resolution” portion of Section 2.5.2, "File, Print..." A value other than 1.0 is required for Screen Scaled By to be different than Screen. Copy/Save Resolution When copying/saving a picture from the screen, you may want more detail than is provided by the Screen resolution. To output at higher than screen resolution, use the Screen Scaled By option. FEMAP creates an off-screen bit-

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map, renders your image to that bitmap, then copies that bitmap to the clipboard or saves it using a specified picture file format. The factor that you specify in this option is simply multiplied by the screen resolution to compute the size of the off-screen bitmap. Therefore, if you specify 2, you get a copied/saved image that uses twice the screen resolution. Be careful not to specify a number that is too large. It will take quite a large amount of memory, and may take a very long time to copy or save. You can also use Screen Scaled With Width to set a width in number of pixels used to scale the image, Screen Scaled With Height to set a height used to scale the image, or Fixed Size, which scales the image to a particular size. Pen Width Choose Auto or Manual Factor. When Manual Factor is selected, this factor is used for plotting directly to a printer and Metafiles. In FEMAP, graphics are normally drawn as “single-pixel-width” lines - that is they are only one dot wide. For high resolution printers, like typesetters, this type of line may appear very faint due to the small size of each pixel on these devices. By increasing the value of the Manual Factor, the width of each line is multiplied by this factor to obtain a print with “fatter” lines. This option has no effect on screen display. The value should be between 1 and 10 (2 is the default). Logo and Background Bitmap Scaling Set the scale factor for a bitmap image being used as a Logo or Background. You may want to set different scale factors depending on the destination of your image. There are options for Screen Scale (Default = 1), Print Scale (Default = 2), and Copy/Save Scale (Default = 1). GIF Options button Sets default options when saving a GIF or Animated GIF file. For GIF files, choose from Network, Octree, and Color Diffusion (Dither). Turning on the Optimized option will remove infrequently used colors in the picture first when reducing to 256 colors. In addition, the Frame Delay may be set for animated GIFs (milliseconds) and an option exists to Save GIF Frame Series. Depending on your machine and other applications where you might be placing saved pictures, one of these formats may produce a better image than the other two or similar image quality using a smaller file size. Hint:

For best image results, use a solid background when creating GIF files. This is due to the 256-color limitation of GIF files.

Hint:

Saving a “test image” once in each format will help you determine which option should be used with your machine and other applications.

JT File Version Sets the default value displayed for “JT File Version” in the JT Options dialog box when saving a picture as a JT file (see Section 2.5.4.7, "File, Picture, Save JT..."). Determining the proper “JT File Version” for software packages which support JT files is up to the user. Available file versions are 8.0, 8.1, 8.2, 9.0, 9.1, 9.2, 9.3, 9.4, and 9.5.

Options These options control various operational features of FEMAP views. Alternate Fill Mode FEMAP fills polygons whenever you turn on element fill or do a hidden line plot, a contour plot, or a criteria plot. Windows provides two different techniques for drawing a filled polygon, both of which should be equivalent for all cases in FEMAP. Unfortunately, some graphics adapters and their drivers have trouble filling polygons with one method or the other. Notably, some of the more “advanced” Windows accelerator boards like the Number Nine, Matrox, and other S3-based boards will often forget to draw a polygon when using the standard filling method. If you see missing spots/polygons when you draw a model (especially a contour plot), try switching the fill method. If that solves the problem, save this option when you exit Preferences so it will be used for all models. Workplane Never Visible in New View This option allows you to turn the workplane off when starting a new model. If this option is not checked, FEMAP will use the setting for the startup view to determine whether the workplane is visible in a new model. If this option is on, FEMAP will automatically turn the workplane off, even if the settings in the startup view call for it to be on.

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Color Palette Use this option to select one of the “Standard Color” options available in the Contour/Criteria Levels view option. Choose from “0..Standard”, “1..No Magenta”, “2..Temperature”, “3..Red Yellow Green”, or “4..Gray”. See Section 8.3.10.3, "Level Modes" for more information. Open Views of Existing Models By default, when you open an existing model, the view of that model automatically opens. Sometimes, however, opening graphics in a corrupt model file can cause a crash. To open a model file without the graphic view of the model, turn off the Open Views of Existing Models option. Once the file is open, you can work on solving the problem, perhaps by writing out a neutral file. You can “manually” open the view by using View, Activate or View, New. Aspect Ratio for New Views When a new view is created, the aspect ratio is normally set to 1.0. The geometry is not stretched either horizontally or vertically for display in that window. An aspect ratio of 2.0 would cause a square to be displayed two times as high as it is wide. Changing this value only sets the default for new views. You can use View, Options to update the aspect ratio for any existing window, and turn off the AutoAspect feature.

View and Dynamic Rotation These options control the rotation of views in your model when using the View Toolbar commands as well as when you access the View, Rotate command. Delta This is the default angle of rotation when you click in the scroll bars in the View, Rotate command or when you use the Rotate buttons on the toolbar. It must be specified in degrees. Dynamic This option chooses the method that will be used for displaying your model during the Dynamic Rotate/Pan/Zoom command from the toolbar. If you experience flashing when you perform a dynamic rotation, set this option to a different mode to remove the problem. This option has no impact on dynamic rotation. Dynamic Speed Allows you to increase the “speed” a model will rotate in the graphics window based on the distance the mouse is moved across the screen. The number must be between 1 and 10 and the higher the number, the greater number of full rotations will occur as the mouse is dragged from side of the graphics window to another. Rotation Angles These options allow you to define three view orientations which can be accessed using the View, Rotate command buttons. The default views are Isometric, Dimetric and Trimetric. In addition to the rotation angles you can also set the button text. Place an ampersand (&) in front of the letter that you want to be able to access using the Alt+Letter keyboard combination.

2.6.2.3 Render Render mode is a high-speed graphics mode that uses the OpenGL graphics language (It is the default graphics mode in FEMAP). The Render tab lets you control Render graphics options and the level of functionality that you have while in Render mode. Note:

FEMAP often performs better when using the “default settings” for OpenGL graphics cards. Issues may sometimes occur when using settings optimized for other applications, especially with animations.

The dialog box has four areas: •

Render Options



Include in Dynamic Rotation



Textures



Advanced/Debug Options

Render Options These options control how Render will be implemented.

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Hardware Accel (startup only) This option controls whether you use hardware acceleration while in the Render mode or if the rendering is to be done by software in Windows. This will be defaulted to on, but will only work when a hardware acceleration board has been installed in your computer. If a board has been installed and you do not wish to use hardware acceleration, you can uncheck this option. You must save this preference and restart FEMAP for this option to take effect. Use Midside Nodes If this option is selected, FEMAP will use the midside nodes when drawing rendered plots. This increases the complexity of the graphics, decreases the speed of drawing the graphics window, and increases memory usage. Memory Optimization When this option is selected, FEMAP doesn’t use as much memory when drawing. This may or may not be helpful, depending on the size of your model: •In very large models that require memory swapping, turning on this option will improve display performance. •In small/medium-size models that don’t require memory swapping, turning on this option may slow down display performance. For small models, you may find this option helpful in viewing arrowheads that represent boundary conditions. If the option is on, the arrowhead will display flat on the screen as the model is rotated. If the option is off, the orientation of the arrowhead will rotate with the model. Multi-Model Memory If this option is on (default) then FEMAP will use memory for the active window of each model currently open in the interface. This improves performance when graphically clicking from one model to another, but uses more of your machine’s memory. When turned off, only the active view from the model currently active in the FEMAP interface will be using memory. This will decrease performance when graphically switching between models, but use less memory. For users with a relatively low amount of memory dealing with very large models, this option should be turned off. Note:

This option does not effect performance when clicking between different views of one model.

Beam Facet Edges On

Off

This option controls how a cross section is displayed on a beam element. When on, the cross section extends along the length of the element. When off, the cross section is drawn only at the ends of the beam element.

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Smooth Lines When this option is on, FEMAP uses OpenGL anti-aliasing to draw smooth lines. This can enhance wireframe displays but can be computationally expensive. Hint:

If you switch it on in Render Options, you can switch it off in Include In Dynamic Rotation to improve dynamic rotation performance.

Auto Regenerate If this option is chosen, a graphics regenerate automatically occurs after virtually every command. The graphics will always reflect the current model status. For large models, this can be expensive and the option should be switched off. By default, this option is off. Fast Render Picking When selected, picking uses “in memory” data to pick nodes, elements, points, and surfaces. This results in much faster picking with large models. If you switch this option off, or use Pick Query or Pick Front, the standard picking algorithms are used. You should leave this option on. XOR Picking Graphics XOR picking effects how entities are highlighted when graphically picking in FEMAP. This was the only picking graphics method in FEMAP before version 10. With the advent of Windows Vista, picking was not able to draw to the screen image directly which made XOR picking much less efficient (slower) on some graphics cards. If XOR picking is “off”, FEMAP basically draws a bitmap of the screen image and then determines the color that is the “XOR” of the entity color and draws the entity twice, once with the “XOR” of the entity color but larger or thicker and once with the entity color. Un-highlighting is done by redrawing the bitmap of the screen. In non Vista hardware, turning XOR picking “on” will likely give better clarity but for Vista, performance is better with it “off”. Edges Using Lines Some graphics cards currently have poor quality support for the standard OpenGL method FEMAP uses to draw element and surface edges. Selecting this option forces all edges to be drawn as simple lines. This is not as efficient and may cause the edges to have a stitched appearance. You should use this option if element edges are not drawn correctly. Dialog Refresh With certain graphics cards, the view will not be redrawn behind open dialog boxes, thus if the dialog box is moved after the model has been dynamically rotated the display may not be correct. When this option is “on”, FEMAP will force a redraw of the graphics window. Vertex Arrays If your graphics card has good support of vertex arrays, you can get significant performance improvement by selecting vertex arrays. FEMAP provides three levels of support (No, Partial and Full) to account for different graphics cards: •

Full Vertex Arrays uses vertex arrays for all graphics. We have seen problems with this level of support on some graphics cards including severe system crashes.



Partial Vertex Arrays uses vertex arrays for all filled entities such as elements and surfaces, but does not use vertex arrays for element and surface borders.



No Vertex Arrays does not use vertex arrays at all.

You should use the level that gives the best performance without any problems. Block Size The block size determines the size of “blocked data” in “collectors” used by FEMAP internally. If you have a few large “collectors”, a larger block size should provide better performance. On the other hand, if you have a large number of small collectors (i.e., often happens with laminates), you might use a great deal of memory with too large a block size, so selecting a smaller block size should be beneficial. Search Depth To optimize memory usage, FEMAP internally groups entities which are exactly the same (same element type, property, material, layer, AND color) together. These “like” entities are stored in “collectors” in the FEMAP graph-

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ics data structures. Every time a new entity is created, FEMAP will search all of the existing collectors to see if the new entity can be placed into one of them. The Search Depth value refers to how many collectors FEMAP should search when a new entity is created before creating a new collector. By default, the value is “10”, which means that FEMAP will search through the 10 most recently used collectors and only create a new one if a collector does not exist with the entity’s same type, layer, color, and other attributes (i.e., property on an element). When Search Depth is set to “0”, FEMAP will search all collectors for matching attributes before creating a new collector. This will create the least number of collectors in the model. In general, searching all the collectors in a model is not an issue, but if you have a model with many different (typically in the hundreds or thousands) entity types, properties, materials, layers, and colors, this can slow down the graphics significantly as FEMAP looks for an existing collector in which to place the new entity. Note:

An example of when you might want to change the Search Depth is: A NASTRAN input deck has been imported into FEMAP with a large number of CELAS2 elements (spring elements which also contain spring property data on each connection entry). Since these elements are not associated with a “property” using a property ID, FEMAP is forced to create a property for each CELAS2 element. Each spring element is now a different property, causing FEMAP to place each one into its own collector. If there where 28000 springs in the model, FEMAP would have to search through 28000 collectors each time a new entity is created and this is not efficient for the FEMAP graphics data structures. Changing the value of Search Depth to a lower number can increase graphics performance by searching the collectors far less often and creating a new one only if no matching collectors can be found.

If you are using the “Auto Transparency” option available for “Transparency” in the Tools and View Style section of View Options (see Tools and View Style category, Transparency option of Section 6.1.5.3, "View, Options..."), it is likely that a Search Depth of “0” is recommended and will likely produce the best image.

Include in Dynamic Rotation These options let you select the entities that will be included in dynamic rotation. By deselecting some of these entities, you can improve display performance. In large models, you may see dramatic performance improvements when you turn off options such as Fill, Shading, Filled Edges, and Undeformed. If you turn Workplane off, some additional entities will also not appear during dynamic rotation. These entities include the Axisymmetric Axis, View Legend, View Axis, Origin, Workplane and Rulers, and Workplane Grid from the Tools and View Style category of View, Options as well as the Post Titles, Trace Locations (Trace Style), and Contour/Criteria Legend from the PostProcessing category of View, Options. If you select Elements as Free Edge, elements will be drawn as free edge only during dynamic rotation. This will greatly improve graphics performance for large models. Connections will turn off Connection Regions and Connectors If you deselect Element Symbols, elements that are drawn as symbols will not be drawn during dynamic rotation. This will greatly improve graphics performance for models that contain a large number of mass, mass matrix, link, gap or DOF Spring elements. Hint:

Remember, you can also use View, Options or View, Visibility to control which entities are displayed.

Textures These options enable you to control the texture maps used by post processing displays. 2D mapping If you select this option, 2 dimensional texture maps will be used; otherwise, 1 dimensional texture maps will be used. Different graphics cards have different levels of support of 1 and 2 dimensional texture maps. Smooth Textures This option is available for 1 or 2-Dimensional texture maps. It can provide better quality smooth contours.

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Force All Triangles This option forces quadrilateral elements to be split into 4 triangles for contouring purposes, instead of only 2. This is especially useful when looking at symmetric results on coarsely meshed models. Some plots may take longer. Also, some graphics cards split quadrilateral graphics primitives differently when they intersect the edge of the window. This can cause the contours on a model to move on an element face when the model is dynamically rotated while intersecting the edge of the window. If you select this option, all quadrilaterals are split into triangles and this gives consistent contours. The vertex colours are always correct: it is only the internal color pattern of an element face that is impacted. Max Size FEMAP tries to use the largest texture map possible. However, some graphics cards do not enable the maximum size to be determined. If you have problems with contour display colors, set this number lower and try again.

Advanced/Debug Options These options help you work with FEMAP Support to resolve Render graphics display problems that may be unique to your graphics card driver. Print Debug Messages If you turn this option on, FEMAP will write print debug messages to the Messages window. FEMAP Support may request this information to help you resolve a graphics display problem. The “Elapsed Time” option reports “elapsed times” of various operations related to FEMAP graphics. Turning on the “All” option will report quite a bit more information, but will also be slower. “OpenGL Errors” will report any errors specifically related to OpenGL. If there are no OpenGL errors, then nothing different will be reported. This option is off by default as it takes additional time to query FEMAP for these types of errors. Bitmap Alignment This option controls the way that bitmaps are stored. The default setting is 4. Changing this setting may cause severe display problems. Do not change this setting unless instructed to do so by FEMAP Support. Pixel Format This option controls graphics descriptors. The default setting of 0 instructs FEMAP to use the optimal pixel format for your graphics board. Changing this setting may cause severe display problems. Do not change this setting unless instructed to do so by FEMAP Support. BitBlt Delay If you are seeing “split images” in your FEMAP graphics window, you may need to enter a value for BitBlt Delay. In some low-end graphics cards, GDI and OpenGL graphics are not synchronized correctly, which can result in “split images” appearing inside the FEMAP graphics window. This is due to the picture capture of the screen occurring while the graphics are still in the swap buffer. In order to correct this problem, a value for the “BitBlt Delay” can be placed into FEMAP to allow extra time (in milliseconds/Megapixal) for the graphics to come out of the swap buffer and the screen image to be captured properly. The time it takes certain graphics cards to get OpenGL and GDI in sync appears to be proportional to the number of pixels in the window. If your graphics window is bigger than 1 Mega Pixels (MPix), the delay will be multiplied by how many mega pixels your screen occupies. This allows users to switch between monitor resolutions without having to change this value. Note:

Usually, a delay of 10 ms/Mpix or 20 ms/Mpix, will correct the issue. If these values do not help, we suggest starting with 100 ms/Mpix and moving back towards 0 ms/Mpix by increments of 10 ms/Mpix until the problem reappears.

2.6.2.4 User Interface When you choose the User Interface tab, the Preferences dialog box will display options for the how the different facets of the FEMAP User Interface (menus, toolbars, dockable panes, tooltips, etc.) will function. This User Interface tab is partitioned into seven categories: •

Menus and Dialog Boxes



Graphical Selection



Mouse Interface

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Meshing Toolbox



Dockable Panes



Model Info



Show Entities Defaults



Toolbars

Any options in the Menus and Dialog Boxes, Graphical Selection, or Mouse interface sections can be changed for a given session.

Menus and Dialog Boxes Alternate Color Scheme If this option is on, the menus, toolbars, and dockable pane borders will appear as a gray color instead of a shaded color regardless of which color is set for dialog box appearance in Windows. FEMAP appears more like pre-Version 9 releases when the Alternate Color Scheme is turned on. Autorepeat Create Commands If this option is on, all entity create commands will automatically repeat until you choose Cancel. This allows you to continue creating entities without repeatedly choosing the same command. Remember Dialog Positions When this option is on, FEMAP will remember the last screen location for each dialog box. If you move a dialog box then pick the command again later, FEMAP will place the dialog box in the position you chose rather than in the default position. FEMAP will remember the dialog box locations only for the current FEMAP session. To restore dialog boxes to their original positions, use the Reset Dialog Positions button. Alternate Accelerator Keys for Views When on, changes the way several Accelerator Keys (hard-coded shortcut keys) function in FEMAP to give quick access to orient the view. Ctrl+B becomes View, Rotate, Bottom; Ctrl+T becomes View, Rotate, Top; Ctrl+F becomes View, Rotate, Front; Ctrl+L becomes View, Rotate, Left; and Ctrl+I becomes View, Rotate, Isometric. These accelerators mimic Solid Edge and FEMAP must be restarted in order for this preference to take effect. Ask for Confirmation Before Delete Unchecking this box will cause FEMAP to no longer show Confirm Delete dialog boxes throughout the program. If you check the “Don’t confirm delete again” box in any Confirm Delete dialog box, the Confirm Delete dialog boxes will no longer appear when you delete an entity and this option will now be unchecked. If you would like to turn the Confirm Delete dialog boxes back on, simply check this option.

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Fast Output Delete This option can be used to dramatically increase the speed of deleting a large amount of output by eliminating the ability to “Undo” after the output is deleted. There are 3 options: •

Confirm - every time output is deleted, FEMAP will ask “OK to Delete Results without Undo? Deleting without Undo can be significantly faster.” Click Go Fast button to move forward without Undo or Preserve Undo.



Fast (No Undo) - Always eliminates Undo after output has been deleted



Preserve Undo - Preserves Undo after output is deleted.

This option will be set automatically to whatever option is chosen if the “Don’t confirm again” box is checked in the Confirm Fast Results Delete dialog box. Recently Used Files This option sets the number of recently used files that will be listed at the bottom of the File menu.

Graphical Selection Track Mouse Picking This option activates dynamic selection tracking. When you move the cursor through the graphics window to select nodes, elements or other geometry, FEMAP dynamically highlights the entity that will be selected if you click the mouse button. This makes accurate selection much easier in complex models. Pick All Inside This option controls selection of entities when screen area (using box or circle) picking is used to select entities whose position is defined by other multiple entities (i.e. elements by their nodes, curves by their points). If this option is on, all entities which comprise the selected entity must be inside the selected area (i.e. for an element, all of its nodes must be in the selected area for it to be picked). If it is off, only one entity must be selected (i.e. for an element, only one node must be in the selected region when this option is off). Pick Method This option controls the default Pick Method for Entity Selection dialog boxes. Choices are “Pick Normal”, “Pick Query”, and “Pick Front”. See Section 4.3.1, "Entity Selection" for more information about the Pick Methods. Tooltip Delay Allows you to set the amount of time before a “tooltip” will appear after an entity has been highlighted by the cursor. The number is in tenths of a second and can be from 1 to 1000. For example, the default value is “10” tenths of a second (i.e., 10 x 0.1 seconds = 1 second after an entity has been selected, a tooltip will appear). Tooltip Duration Allows you to set the amount of time a “tooltip” will be visible after it appears. The number is in tenths of a second (For example, the default is “100” tenths of a second, therefore, 100 x 0.1 seconds = 10 seconds that the Tooltip will be visible). If you want to set the Tooltip to remain visible until the cursor is no longer selecting that entity, you can set the value to “0” (zero).

Mouse Interface Reverse Mouse Wheel Direction By default, when the mouse wheel is used to zoom in and out inside the main FEMAP graphics window, spinning the mouse wheel up (away from the user) will zoom out, while spinning the mouse wheel down (towards the user) will zoom in on the model. When this option is checked, the direction of the mouse wheel will be reversed for the FEMAP graphics window only (the mouse wheel will work normally in any other Dockable Pane), therefore spinning the mouse wheel up (away from the user) will zoom in, while spinning the mouse wheel down (towards the user) will zoom out on the model Shift for Pan, Ctrl for Zoom By default, when the Shift key is held down along with the left mouse button (or mouse wheel is pressed when a dialog box is open) moving the mouse up or down will allow you to dynamically zoom in and out of the model. Also, when the Ctrl key is held down along with the left mouse button (or mouse wheel is pressed when a dialog box is open) moving the mouse up, down, left or right will allow you to dynamically translate the model around the screen in the corresponding direction. When this option is checked, the functionality of holding Shift or Control

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down along with the left mouse button and moving the mouse around will be swapped (i.e. Shift for Pan, Control for Zoom).

Meshing Toolbox Expand Active Tool Only and Auto Remesh Sets the defaults for Expand Active Tool Only and Auto Remesh in the Meshing Toolbox. Both “on” by default.

Dockable Panes Animate Fly-out This option is used when a Dockable Pane is in the “retracted” state (Retracted means that the pane is only visible as a tab and will fly-out when the curser is placed on the tab). This preference, when on, will animate the “fly-out” from the tab to full extension of the pane. The “Retraction” (when the pane goes from being fully extended back to tab only) will also be animated. When this preference is off, the pane will just “pop-up” to full size and then “minimize” to tab only instead of you viewing it extend and retract. This is a “start-up” only preference, therefore it the preference must be saved and FEMAP reopened in order for it to take effect. Captions Always on Top This option will force the Title Bar of any “docked” dockable pane to always be on the top of the pane, regardless of where the pane is currently docked. By default, dockable panes which are docked on the top or bottom of the graphics area will have the title bar displayed on the left side of the pane to use less space vertically. Alternate Docking Symbols This option simply allows you to choose which “Docking Position Indicators” are displayed in FEMAP. See below. Default Indicator

Alternate Indicator

Model Info Max Entities Limits the number of items of each category which will be shown in the Model Info tree. This can significantly improve performance if you have thousands of entities of one type. Options are added to the tree to show the next or previous group, whenever less than the full number of entities are displayed. The default value is 2000. Create Automatic Titles When on (default), FEMAP will create titles automatically for Materials and Properties based on the type of Material or Property being created. When off, Materials and Properties will be untitled.

Show Entities Defaults These options are the same options for highlighting entities that are found in the Window, Show Entities... command. For more information, see Section 6.3.2.3, "Window, Show Entities...". FEMAP will use these default settings for all new models and until the any of the options are changed by the user manually. The options can be changed using the Window, Show Entities... command, the Show When Selected icon in the Model Info tree, or the Show When Selected icon in the Data Table.

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Toolbars Save Layout When the Save Layout button is pushed, FEMAP will prompt you to save your User Interface layout to a *.LAYOUT file in a directory of your choice. You will be prompted to choose which portions of the current installation’s User Interface (Menu and Toolbars, Panes, Shortcut Keys, and User Commands) to save to the *.LAYOUT file. The *.LAYOUT file can be used to bring a specific User Interface layout to a different installation of FEMAP. Load Layout When the Load Layout button is pushed, FEMAP will prompt you to select a *.LAYOUT file from a directory of your choice in order to load a User Interface layout from an existing installation of FEMAP. This allows one layout to be used by multiple users. Reset User Interface Resets the FEMAP User Interface to the original configuration when the product was installed, by deleting all of the registry settings associated with FEMAP toolbars, dockable panes, menus, shortcut keys, and user-defined commands. When this command is used, the following message will appear: “OK to Reset Interface? Resetting the user interface will lose all customization. You must exit and restart to complete the reset.” If you click Yes, all toolbars or menus that have been changed (icons and commands added, moved, removed); all altered icons; all toolbar positions, all custom toolbars; all dockable pane positions, pinnings, and stackings; all user-defined shortcut keys; all custom commands that have been created; and all toolbar options which were chosen will be changed back to the defaults and can not be recovered unless you have saved them in a Toolbar layout (*.LAYOUT file). You must exit and restart FEMAP for this command to take effect. Hint:

Saving the toolbar layout to a *.LAYOUT file is a good idea before using the “Reset User Interface” command, as it will allow you to return to custom commands and shortcut keys if you need them in the future. You can always load them for use and then use the Reset User Interface command to get the defaults back again.

Note:

Using the *.LAYOUT file is a good way to recreate a customized FEMAP interface in a particular version of the software. If a *.LAYOUT file is loaded into a newer version of the software, the “Shortcut Keys” and “User Commands” will be updated, while “Menus and Toolbars” and “Panes” will not. For FEMAP 10.3 and above, “User-defined” Toolbars will be imported into newer versions. If you want to bring in a customized version of a “standard” toolbar, it is probably best to create your a “Userdefined” toolbar with the same commands, then customize that “User-defined” toolbar so it will be brought into the new version without overwriting any existing menus or toolbars.

Reset Dialog Positions Resets the FEMAP dialog box positions to the original positions when the product was installed. This command only has an effect if you have the Remember Dialog Positions option checked in the Menus and Dialog Boxes portion of this dialog box.

2.6.2.5 Database The options on the Database tab control certain database options, including memory management and location of scratch files. All of these options, with the exception of those labeled “immediate”, are only used at startup. You must therefore restart FEMAP after changing any of these option to have them take effect. The Database tab of the Preferences dialog box is partitioned into four areas: •

Database Options



Database Performance



Timed Save



Scratch Directory

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Each area is discussed more fully below.

Database Options These options control how FEMAP interacts with the FEMAP model file (binary database). Backup before Save When this option is on and your model has been saved previously, FEMAP will keep a backup copy of your model in the file modelname.BAK (where modelname.MODFEM is the name of your model). Only one backup copy is saved, so the .BAK file will be updated and overwritten every time you save. By default this option is disabled, and no backup copies are saved. Unlike the other options in this dialog box, changes to the backup option are effective immediately. You do not have to save them permanently. The backup option is ignored whenever Use Model Scratch File is off. In this state, you directly update the model file during every command, not just when you choose Save. Therefore, FEMAP does not attempt to make a backup when you save. Delete Model Scratch File When this option is on, FEMAP will automatically delete your scratch file whenever you begin a new model or exit FEMAP. The option is selected as a default. Preserve Next ID during Rebuild By default, FEMAP will reset the “Next ID” for all entities to the lowest available ID after the File, Rebuild command has been used. When this option is on, FEMAP will maintain the “Next ID” defined for all entities prior to the “Rebuild” operation. This will prevent FEMAP from “back-filling” empty IDs that may exist in a model that has been somehow partitioned using entity IDs. Low Disk Warning When this option is on, FEMAP will issue a warning when free space on the scratch file’s disk drops below the amount specified. Undo Levels Controls how many commands (0-99) that you will be able to undo. Setting this to a larger number gives you greater flexibility in being able to backup your commands, but can take a significant amount of disk space. All files are placed in the specified Scratch Directory.

Database Performance These options control how FEMAP uses your computer’s RAM. Setting these properly can greatly improve performance. Database Memory Limit The Database Memory Limit sets the maximum amount of system memory that FEMAP will use to hold parts of your model and results in memory. If your model is larger than the amount of memory that you choose, FEMAP will automatically read data from your disk as it is needed, replacing data that is not being used. While this “Swap-

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ping” process can slow down overall performance, it does let you work with much larger models than would otherwise fit into your available memory. The Database Memory Limit DOES NOT control the total amount of memory that FEMAP will be using. FEMAP uses memory for many different operations – this is just one of them. Almost every command temporarily uses some small amount of additional memory. Some commands, like meshing, node merging and reading results can temporarily use fairly significant amounts of memory. Other operations, like loading large amounts of data into the Data Table require memory for a longer period of time – in this case as long as the data is in the table. Finally, the largest use of additional memory, and one which normally persists the entire time you have a model open is for drawing your model. For optimal performance, FEMAP uses OpenGL graphics, and keeps copies of the data to be drawn in memory at all times. You must always have sufficient free memory available for all of these uses, or the operations will not be able to execute properly. In the very worst case scenario, running out of memory could cause FEMAP to crash. It is for this reason that the default Database Memory Limit is set fairly low – 20% of the memory in your computer (The 32-bit version is also restricted by the 2 GByte limit for any program). This does not mean that you can not increase the limit beyond its default, but the further into the yellow and red zones you push the slider, you are increasing the chance of running out of memory. Note:

Changing the Database Memory Limit does not change the amount of memory used for the current session. For this selection to take effect, you must exit and restart FEMAP.

Using the Control The slider control allows you to choose the amount of memory to use for the database. Move the slider to the left to reduce the limit, to the right to increase it. As you move the slider, the memory limit is updated and displayed above the slider. The colored bar below the slider gives you an indication of the risk of running out of memory if you use this setting. The yellow and red regions should be used with caution since there is a good chance of causing problems with other operations like meshing and graphics. The small line along the top edge of the green section indicates the default memory limit. It is simply displayed to make it easy for you to go back to that limit if you try other settings. The blue bar along the bottom edge indicates the amount of memory that the database is currently using. Note:

The blue bar in the above figure shows the amount of memory used by a 1,000,000 element model (4noded plate elements) on a 32-bit machine with 2 GB of RAM. Most potential problems with exceeding the 2 GB memory limit only occur with very large models.

With this option, you are simply setting the maximum amount of memory available for the database. If you are working with a smaller model, FEMAP will not use memory that it does not need and the blue bar will not extend the entire way to the slider setting. If you look at this control with an empty model, or if you have a small model and a large amount of memory in your system, the blue bar may not be visible – because it is too short to be seen along the bar. Max Cached Label Sets the largest label that FEMAP will reserve memory for. This option must be set to a ID higher than any entity in the model. Default value is 5,000,000. Blocks/Page This value sets the “page” size. The optimum setting of this number often depends on the speed of your disk and controller. Note:

The default value of “4” was determined via testing to produce the best performance over a wide range of values for Database Memory Limit and using the default settings for a number of different types of disk drives. You may want to try other values from 1 to 15 if you have changed any speed/caching settings on your drive or have “high-speed” drives to determine if performance is improved.

Open/Save Method and Read/Write Test button The Open/Save Method option should only be used if you are experiencing VERY slow opening/saving FEMAP model files. On certain hardware, switching to option “2..64K widows I/O” may make a dramatic difference in the

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time a model takes to open/save. Essentially, what option 2 does is copy to (opening) and from the scratch directory (saving) in 64K “blocks” instead of allowing the hardware to choose the size. Options 1 and 3 are simply other alternatives to try. The Read/Write Test may be used to determine which Open/Save Method should work best on your machine. It reads and writes a series of 12 100 MB files using various “block sizes” to determine the method. ( . When finished, results of the test will be written to the Messages window and the “recommended” setting will be displayed in the Open/Save Method drop-down. Note:

You will need 1.2 GB of free disk space to run the test properly. If FEMAP detects you have less than this, it will only perform the test with 4 100 MB files (64KB and 100MB for both Windows and C I/O).

Timed Save On and Notify The selected option specifies if FEMAP should notify you when it hits a preset limit or if it should just automatically save the model. Interval and Commands The Interval sets the time in minutes between automatic saves, while the number of Commands set the number of commands performed before FEMAP notifies you that it has performed an automatic save.

Scratch Directory This option determines where temporary files will be placed. Both the Model Scratch file and the Undo Files will always be saved in the same directory. •

The Model Scratch file is always turned on. The scratch file is a duplicate of your model file and therefore is the same size.



The size of the Undo Files depends upon how many levels of undo you choose and the FEMAP commands that you execute. They can be large.

The model scratch file is not deleted (unless you request deletion using the Delete Model Scratch File option, which is the default), when you exit FEMAP, but all other files are deleted. For Windows XP and Vista the directory path to the Scratch Directory should be complete path names. If the path is not specified these files are stored, by default, in the directory specified by the TEMP environment variable.

Recover Scratch Directory As FEMAP models, it creates temporary files in the Scratch Directory. These files are necessary so FEMAP can keep track of changes to the FEMAP database during the modeling process, but in general can not be used for anything on their own. When you the File, Save command is used in FEMAP, the model information is first “dumped” to the scratch directory, then the model file is “opened” in its saved location and the updated information is transferred to that location. If for some reason (usually running out of disk space), FEMAP crashes during the File, Save command and the information has been “dumped” to the scratch directory and the model file has been corrupted or disappeared, then the model can be recovered by clicking this button. When this happens, FEMAP should automatically prompt you to perform this action the next time FEMAP is started after the issue occurred. Note:

The Recover Scratch Directory command is not designed to recover the model from any crashes that occur during the modeling process. It is strictly for use when the model has been corrupted during the File, Save command. As always, it is recommended that you save your model as often as possible.

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2.6.2.6 Geometry/Model The Geometry/Model tab contains geometry options such as choosing the Geometry Engine for solid modeling, the Solid Geometry Scale Factor, and how Construction Geometry will be handled after it has been used.

There are also options for Load Expansion on Midside Nodes of elements, specifying defaults for Element Quality and Output Orientation, and several options for Meshing and Properties. Each of these are described below. Geometry Engine (startup only) FEMAP can perform solid modeling with the Parasolid Solid Modeling engine. This option controls the default geometry engine upon entering FEMAP. If you do not plan to export a solid model, you may use the FEMAP standard geometry engine to create wireframe and volume geometry. When importing solid geometry, FEMAP will automatically switch to the Parasolid geometry engine. In particular, when ACIS solid geometry is read into FEMAP, it will automatically invoke the ACIS-to-Parasolid converter and all geometry modification and creation inside of FEMAP will be done using the Parasolid engine. Solid Geometry Scale Factor The Internal Scale Factor is used to reduce the size of the part in the FEMAP database. The internal engine of Parasolid requires all positions be in a box of +/- 500. If you have entities outside of this box, Parasolid cannot perform operations on them. By using an internal scale factor, FEMAP can scale the part internally to prevent the part from extending beyond this box. You will not see changes in the dimensions of the part since FEMAP will do all scaling internally. This option allows the input of very large dimensions for the model, without exceeding the limits of the Parasolid geometry engine. By default the Solid Geometry Scale Factor is set to “0..Inches”, which automatically sets a value of 39.37 (i.e., inches to meters conversion) and this factor is applied internally in FEMAP so that a part of 1.0 on the desktop will be stored as 0.0254 in the database. The default factor of 39.37 will allow you to import and model parts that are +/ - 19,685 units. Without the scale factor the geometry would be outside of the Parasolid modeling limits and would

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become corrupt. The default of 39.37 is chosen since it allows you to import a part that was modeled in inches in CAD software, and continue to work in inches without manually having to scale the part. You can also choose to set the Scale Factor to “1..Meters” (value of 1.0), “2..Millimeters” (value of 1000.0), or “3..Other”, which allows you to specify a value of your choice. This is a startup preference; therefore, you must save the preference and exit FEMAP for it to take effect. Construction Geometry - when used Allows you to choose how “construction geometry” will be handled in FEMAP after the construction geometry has been used by another geometry command. In simplest terms, “construction geometry” is a curve used to create a surface using certain methods on the “Geometry, Surface...” menu (Edge Curves, Aligned Curves, Ruled, Extrude, Revolve, and Sweep) or a surface or boundary surface used to create a solid via extruding or revolving. Construction geometry also includes any curves used by a “construction surface” and all points on “construction curves”. FEMAP has three options for handling “construction geometry”: •

0..Delete (default) - All “construction geometry” will be automatically deleted from the model after use by one of the geometry commands specified above.



1..Move to NoPick Layer - Moves all “construction geometry” to layer “9999..Construction Layer”. Layer “9999” is always the default “NoPick Layer”. When an entity is on the “NoPick Layer” and that layer is visible, entities can be seen but not selected from the graphics window. You will need to change the “NoPick Layer” to “0..None” in order to select these entities graphically if you would like to use them again for any reason.



2..Do Nothing - “Construction geometry” will not be moved to Layer “9999..Construction Layer” and will also not be deleted from the model. All “construction geometry” will remain in the model on the original layer and be available for graphical selection when the layer containing the geometry is visible.

Note:

The only option available for “construction geometry” in FEMAP prior to version 10, was “1..Move to NoPick Layer”, so set this option to have FEMAP handle construction geometry as it has in the past.

Automatically Adjust Geometry Scale Factors Adjusts the solid geometry scale factor of imported geometry to match the scale factor of the model. For instance, if you read in geometry with a scale factor of “1” it will be imported and sized in FEMAP with a scale factor of “1”, then adjusted to whatever is set as your Solid Geometry Scale Factor in the Preferences. Having geometry with the same Solid Geometry Scale Factor is very helpful when modifying or creating additional geometry in FEMAP.

Load Expansion on Midside Nodes This section sets the defaults for modification of the distribution of nodal loads (such as force and moment) on parabolic elements. To obtain an even distribution of force across a parabolic element, most programs require a larger portion of the force be assigned to the midside nodes. You can set the factors Along Edges, On Tri-Face, or On Quad-Face to represent the amount of the total load on the element which will be applied to the midside node. You will typically want to use the default values above, as well as use the Midside Node Adjustment Default. If you have further questions on the distribution required for your solver program, please consult the reference documentation for your analysis program.

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Element Quality... This dialog box allows you to set default values used when checking element quality. Also, choose which element checks will be “on” by default when using Tools, Check, Element Quality. The Element Quality checks are: •Aspect Ratio •Taper •Alternate Taper •Internal Angles •Skew •Warping •Nastran Warping •Tet Collapse •Jacobian •Combined •Explicit Time Step The values set in this dialog box will be used for element quality every time FEMAP is opened. If you change the values while FEMAP is open, those values will persist until that session of FEMAP has been closed. Pressing the Permanent button when using the Tools, Check, Element Quality command will update these default values. See Section 7.4.5.6, "Tools, Check, Element Quality..." for details.

Output Orientation... This dialog box allows you to choose the default orientation of the “X” direction for different types of output for different element types. The options set in this dialog box will be the default values set for all new models. These options can be changed “on the fly” for a particular model when using the Model, Output, Transform command (see Section 8.5.8, "Model, Output, Transform...") or when using the “Transformation” functionality of the View, Select command (see Section 8.2.2.2, "Selecting Data for a Deformed or Contour Style"). The Current Output Orientation dialog box contains the “default” output orientation for both Plate and Solid elements. For plane elements, there is an option for each type of output data to transform (Stress, Strain, and Force), for each plane element shape that may appear in the model (Tria3, Tria6, Quad4, and Quad8). Defaults are for Nastran. Consult your analysis program’s documentation concerning the original coordinate system definition. There are two options for triangular elements (“0..First Edge” or “1..Midside Locations”) with the default being “0..First Edge” First Edge

Node 1

Midside Locations

Node 2

Node 1

Node 2

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“0..First Edge” orients the element X-direction to a vector between “Node 1” and “Node 2” of the element, while “1..Midside Locations” orients the element X-direction to a vector from the “midpoint” between “Node 1” and “Node 3” to the midpoint between “Node 2” and “Node 3”. There are three options for quadrilateral elements (“0..First Edge”, “1..Midside Locations”, or “2..Diagonal Bisector”) with “2..Diagonal Bisector” being the default. First Edge

Node 4

Node 1

Node 3

Midside Locations

Node 4

Node 2 Node 1

Node 3

Node 2

Diagonal Bisector

Node 4

Node 1

Node 3

Node 2

“0..First Edge” orients the element X-direction to a vector between “Node 1” and “Node 2” of the element, while “1..Midside Locations” orients the element X-direction to a vector from the “midpoint” between “Node 1” and “Node 4” to the midpoint between “Node 2” and “Node 3”. “2..Diagonal Bisector” orients the X-direction of the elements to a vector originating from the point where a line from “Node 2” to “Node 4” intersects a line from “Node 1” to “Node 3” and extends out following a vector which bisects the angle from “Node 2” to the “Intersection point” to “Node 3”. For solids, there are three orientation options (“0..Material Direction”, “1..Global Rectangular”, or “2..Element”) for different material types associated with solid properties (Isotropic, Anisotropic, and Hyperelastic). See the Solid Element Properties portion of Section 4.2.2.3, "Volume Elements" for more details. Pressing the Reset button when the Current Output Orientation dialog box is accessed through the Preferences will reset all of the output orientation options to the default values set when FEMAP is first installed.

Meshing and Properties Surface Meshing in Memory This preference determines whether additional memory will be allocated by the FEMAP boundary mesher. If this option is selected, FEMAP will allocate new memory to create the mesh. If it is not selected, FEMAP will utilize the memory allocated in the database to perform the mesh. By allocating new memory, the FEMAP mesher can run significantly faster than if it is limited to the database memory. Therefore, this option should almost always be turned on. The only reason to turn this option off is if the available memory on the current machine is low enough that allocation of new memory is extremely limited. Use Fast Tri Mesher The fast tri-mesher option uses a method to create triangles that generally produces fewer triangles with better aspect ratios. When this option is on, the FEMAP surface mesher will use the fast tri-mesher by default. You can also control the tri-mesher from the Automesh Surfaces dialog box (see Section 5.1.3.3, "Mesh, Geometry, Surface..."). Alternate Section Property Calculation Uses an alternate “Alternate Section Property Calculator” to determine the section properties for a Beam element property. For more information about the “Alternate Section Property Calculator” see Special Note about the Alternate Section Property Calculator in Section 4.2.2.1, "Line Elements" Pre-v10 Tet Meshing and Pre-v10 Surface Meshing The tetrahedral and surface meshing in FEMAP has dramatically changed for version 10. You will find in the “options” of several of the Mesh, Geometry... commands, there are check boxes to use the “pre-v10” meshers. These two switches in the preferences allow you to always use the “pre-v10” tetrahedral and/or surface meshing if you feel more comfortable with these meshers and the associated default values they use.

Interfaces

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Mesh Sizing FEMAP has three options for mesh sizing, “Parametric”, “Equal Length”, and “Parametric/Equal Length”. The default is “Parametric/Equal Length”. When set to “Parametric”, FEMAP mesh sizing along curves is done in the parametric space of curves. In many cases this is desirable resulting in finer mesh in areas of high curvature. In some cases however (such as unstitched geometry or geometry that has curves with unusual parameterization), “Equal Length” based spacing will yield much better results. Especially when dealing with unstitched geometry, length based sizing will produce meshes with matching nodal locations far more reliably than parametric spacing. “Parametric/Equal Length” sizes all curves using the “Parametric” option, then determines an “average distance” between each of the “mesh locations” on each curve. If the distance between any of the mesh locations is more than 1% different than the “average distance”, then that curve is resized using “Equal Length” sizing. Note:

Using “Length Based Sizing” can be very helpful for setting up mesh sizing if your geometry has come from Catia. The parameterization coming from Catia is often much different than what other CAD packages produce, therefore our “parameter based mesh sizing” is not as effective with this geometry.

2.6.2.7 Interfaces This section controls defaults for interfaces to other programs. When you select the Interfaces tab, the following options will appear in the Preferences dialog box:

The Interfaces tab of the Preferences dialog box is partitioned into five areas: •

Interface defaults (Specify default Solver, Analysis Type, Interface Style, etc.)



Analysis Monitor Options



File References Options



General Solver Options

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Finite Element Modeling

Nastran Solver Options

Detailed descriptions for each of the available options is provided below. Interface This option simply chooses the default analysis program that FEMAP will display for the File, Import (or Export) Analysis Model, and File, Import, Analysis Results commands. You should set this option to the interface that you use most often. Analysis Type This option chooses the default type of analysis that will be performed. Set this to the type of analysis you perform most often. Non-FEMAP Neutral Version To export a FEMAP model to some external analysis programs (CAEFEM, CDA/Spring, CFDesign, SINDA/G), you use a neutral file. If your external program requires a previous version as input, use this option to set the neutral file version. For example, an older version of CAEFEM may require a FEMAP version 6 neutral file rather than the current version. Neutral Digits Use this command to set the number of significant digits for real numbers in the neutral file. Interface Style These options mask commands for users of some analysis programs. The two thermal options will configure FEMAP in a thermal mode only, changing many dialog boxes. Many structural options will be hidden, and you will no longer have access to them. The thermal options are is only recommended when performing modeling specific to thermal analysis and exporting to a thermal specific program. •

Structural makes all commands visible. Most users should use this option.



Thermal displays only thermal properties in material dialog boxes. This option can be used by structural analysis program (such as Nastran) users who are performing thermal analyses.



Advanced Thermal displays only thermal properties in material dialog boxes, and limits the element types available. This option is for SINDA/G users only.

Enable Old Analysis Interfaces When this option is on, interfaces to ALL solvers supported in FEMAP will be shown when importing or exporting analysis files. Note:

The “Enable Old Analysis Interfaces” should not be used as these interfaces are no longer maintained and have not been updated since FEMAP version 8.0. Please see Section 2.3, "Importing/Exporting Files" for more information on using the Analysis Set Manager.

Analysis Monitor Options • Automatically Load Results: This option will set FEMAP to automatically read results when using the Analysis Monitor. •

Max Lines to Monitor: Sets the default for the number of lines that are monitored from the Analysis Monitor.

File Reference Options • Check References on Open: Toggles on and off checking the selected references (found in File, References) when a model is opened. •

Create Geometry References: When this option is on, a geometry reference will be created automatically for each piece of geometry when it is imported.



Create Analysis Model References: When this option is on, an analysis model reference will be created automatically for each analysis model when it is imported.



Create Analysis Results References: When this option is on, an analysis results reference will be created automatically for each analysis result set when it is imported.

All options are off by default. For more information on references, see Section 2.4.2, "File, References..."

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General Solver Options Run Analysis using VisQ Turn on this option to use VisQ, the Visual Queue Manager for FEMAP, to run an analysis. This option will check the Run Analysis using VisQ option by default in the Analysis Set Manager. Skip Comments when Exporting When this option is on, FEMAP will not write any comments into the input file. Comments include FEMAP names and IDs for corresponding groups and sets. Header information indicating the version of FEMAP used and the date the file was written will also not be written. Compute Principal Stress/Strain When this option is on and you read analysis results, FEMAP will automatically compute principal, Von Mises, max shear and mean stresses and strains if they have not been read, and if all required XYZ components of stress/ strain have been read. You can turn this option off if you do not want to post-process these output quantities. Turning this option off can result in substantial speed improvements during the final phases of reading results. You may also want to turn this option off if your analysis program already computes these values. FEMAP does not compute new values if results exist already, but the checking procedure for these vectors will take some time, especially in extremely large models. Assume Engineering Shear Strain Turn on this option to assume that the shear strain read from the solver results is engineering shear strain rather than actual shear strain. Since shear strain is used to calculate the principal stress/strain values, it’s important to specify the shear strain method. Nastran Solver Options Using MSC/MD Nastran 2004 or later Must be turned on when using MSC Nastran 2004, 2005, 2007, or any MD Nastran version in order to make sure that Nastran creates a compatible binary results file (.op2) that can be read into FEMAP correctly. It is a good idea to select this option if you are always using MSC Nastran 2004 or above for analysis. Note:

If you are using multiple versions of MSC/MD Nastran (Any MD, 2007, 2005, 2004, 2001, 70.7, 70.5, etc.) you may want to use the options available in the MSC/MD NASTRAN Version section of the NASTRAN Executive and Solution Options dialog box found in the Analysis Set Manager to choose the specific MSC/MD Nastran version on a case-by-case basis

Improve Single Field Precision When this option is on, FEMAP will write all values specified using “scientific notation” or longer than 8 characters to the Nastran input file without the “E” designation. For instance, a value such as “4.86111E-4” in FEMAP would appear in the Nastran input file as “4.8611-4” when this option is on instead of “4.861E-4”. Small field only. Write Alternate Line Continuation When this option is on, FEMAP will write all Nastran line continuation markers to “+” only. The only exception is for the “Basic Cylindrical” and “Basic Spherical” coordinate systems written out to every Nastran file by default. Previous versions of FEMAP would write “descriptive” continuation markers, which can be turned on again by turning off this option. Output Set Titles When this option is set FEMAP will use the specified type of Nastran title when reading output from the .op2 or .xdb results files. Options available are TITLE, SUBTITLE, and LABEL. Note:

This option is not available when importing results from the .f06 results file.

Solver Memory (Mb 0=Auto) Allows you to allocate the amount of memory for Nastran to use when solving. If you leave this field blank, Nastran will use the value currently set in your Nastran Resource file (Nast*.rcf located in the “conf” directory for NX Nastran 4.0, 4.1, or 5.0), which by default is often set to “memory = estimate” (NX Nastran will try to determine how much memory the job requires). This is usually recommended.

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The mechanism FEMAP uses to set this option is to add a command line option (memory = VALUE mb) when the job is submitted. This will override the value currently set in your Nastran Resource file. Note:

Please refer to NX Nastran documentation for more information on setting the correct memory value for the solver. Allocating more memory than your machine has can cause the solver to fail and setting this value too low can cause the solver to be less efficient.

Scratch Directory Allows you to select the “Scratch Directory” for NX Nastran to use: •

Nastran Default: Directory chosen during installation to use for creating NX Nastran scratch files.



Femap Scratch: Directory specified in the Database tab of the Preferences dialog box, where the FEMAP has been directed to place the FEMAP scratch file.



Output Directory: Directory specified by the Direct Output To option on this tab of the Preferences dialog box.

The Include Database Files in Scratch Option will make sure the Nastran files (i.e., *.DBALL, *.MASTER, *.OBJSCR, *.SCR300, *.SCRATCH, etc.) are also written to the specified Scratch Directory for Nastran. This is accomplished by using the “dbs” Nastran command line option when running the analysis. Direct Output To Allows you to select the directory to direct all Nastran output: •

Current Directory: Last used directory by FEMAP. If a model has been saved to a directory, the output will be directed to that directory when this option is on. If you have opened a model, imported geometry, or imported a FEMAP neutral file from a directory, then that is now the “current directory”.



Model File Directory (default): The directory where the model file currently being used in located. All output will go into this directory until the model is saved somewhere else. Importing geometry or neutral files from other directories has no effect on where the output will be sent. If you are working on a model that has not been saved, the output will be directed to a temporary directory until the model is saved.

Note:



If you are using the Model File Directory option, and you have a model that has never been saved (i.e., open FEMAP, create a model, then run in NX Nastran without saving), then the output files will be directed to the FEMAP “Scratch directory” specified on the Database tab of the Preferences dialog box. This is only the case for completely unsaved models.

Specified Directory: This option allows you to send all NX Nastran output to a directory that you have specified. You can us the “...” browse button to select a directory. This can helpful because your output will always be in the same place if you need to view the files or “clean-up” leftover output files from old analysis runs.

Note:

If you are using the Specified Directory option, it is a good idea to create a directory specifically for this purpose only, such as C:\Output.

Use ILP 64-bit NX Nastran If you have NX Nastran installed on a 64-bit system, this option will instruct NX Nastran to solve using the “ILP” version of 64-bit Nastran. “ILP” is able to allocate more memory than “regular” 64-bit Nastran by using a 64-bit word size and 64-bit memory pointer, while integers are 64-bits and floating point uses one 64-bit word. Write All Static Load/BC Sets When this option is on, FEMAP will write ALL loads and constraint sets to the Nastran input file for Linear Static Analysis. This essentially forces FEMAP to write out Nastran input files for SOL 101 the way it has in all versions before FEMAP 10.1. Read Comments as Titles When you write out a Nastran file from FEMAP, you can write out titles (such as property or material names) as comments. Turn on this option to read in these comments when you import the Nastran results back into FEMAP. This option works best reading in comments as material and property titles. It may not read in comments as function, load set, or constraint set titles.

Interfaces

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Read DirCos for Solid Stress/Strain This option can be used when you wish to retrieve the direction cosines for solid stress/strain post-processing information from your analysis program. Previous versions of FEMAP would ask you if you wanted to read this data during the results import process. This is off by default since the direction cosine information can be quite large and most users do not use this information. Delete Read Synthetic Load Sets When importing a Nastran input file, several additional load sets are sometimes created to facilitate combinations of structural, thermal, and dynamic loads. FEMAP allows different types of loads to be in a single load set, so often these additional load sets are not required after they have been assembled. When this option is “on”, FEMAP will simply delete these component load sets, as they are no longer needed. Create Groups from INCLUDE files This option will automatically create groups based on INCLUDE statements found in imported Nastran input files. Each INCLUDE statement points to a different Nastran input file. The entities found in each unique input file will be placed into a separate group. INCLUDE statements may point to files which also contain INCLUDE statements, creating a “nested” hierarchy. If this is the case, FEMAP will create a “Referenced Group” containing groups (regular or referenced) automatically created from INCLUDE statements. Therefore, it may be possible to have a “referenced group” which references any number of other “referenced groups” or “regular groups”. This is all done to try and keep the hierarchy of the original Nastran input file in place via groups in FEMAP. Auto Answer Post Questions button Pressing this button will display a dialog box which will allow you to toggle “Auto Answer” check boxes for a variety of questions which may appear in dialog boxes during import of Nastran results from .f06 file. One additional General Question may also be “auto-answered” with regard to reading Nonlinear Stresses and Strains from the .f06 and .op2 files. When the check box next to an option is “checked”, FEMAP will “Auto Answer” the dialog box question related to that option with the answer specified in the drop-down menu (“0..No” or “1..Yes”) to the right of the option. If the check box is “not checked”, FEMAP will display the question in a dialog box and await manual response from the user. Here is a detailed description of each option: Output Contains QUADR Elements - When importing results following analysis with MSC Nastran where XY PLOT info has been written to the .f06 file, FEMAP will ask “Is Output on QUADR/TRIAR elements?”. If you have QUADR/TRIAR elements in your model, then you should answer this question with “Yes”, if not, answer “No”. It is very important to make sure this question is answered correctly. If not, the imported XY output data will not be given the correct title, and in certain cases, entire functions will not be read into FEMAP. Output Contains Corner Output - When importing results following analysis where XY PLOT info has been written to the .f06 file, FEMAP will ask “Does Output Contain Corner Data?”. If you have requested corner data for any elemental output from the analysis, then you should answer this question with “Yes”, if you have not, then answer “No”. It is very important to make sure this question is answered correctly, because if you have requested corner data and answer “No”, or have not and answer “Yes”, the imported XY output data will not be given the correct title, and in certain cases, entire functions will not be read into FEMAP.. Note:

If you have NO output types “checked” in the “Elemental” section of the Nastran Output Requests dialog box in the Analysis Set Manager, then you do NOT have corner data output in your model. If you have any output requested in the “Elemental” section, then the “Element Corner Results” option in the “Customization” section of the Nastran Output Requests dialog box determines whether the resulting output file contains corner data (checked) or not (unchecked).

Read PSD/Freq functions - When importing results following Random Response analysis, FEMAP will ask “OK to read PSD vs. Frequency Functions?”. If you have requested this type of output using the NASTRAN Output for

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Random Analysis dialog box in FEMAP or directly in the Nastran input file, this data is always imported from the .f06 file, even if the rest of the results reside in an .op2 file. Read Corner Output - If “Element Corner Results” were requested when an analysis job was run, FEMAP will ask “OK to read plate element corner stresses?” or “OK to read solid element corner stresses?” when importing results using a .f06 file into a model containing various plane or solid elements. By answering “Yes”, FEMAP will import all of the additional output related to the element corner results. This “corner data” is always imported when using .op2 files. Hide f06 Warning Dialog - When checked, FEMAP will NOT display the “Message Review” dialog box. This dialog box allows you to simply “Continue” with importing of results or “Show Details” which consists of fatal errors, warning messages, and information messages written to the .f06 file during analysis. Once reviewed, the results may then be imported. Read Nonlinear Output - When a nonlinear analysis is run using Nastran, both Nonlinear stresses/strains and “regular” stresses/strains are available in the output file. An Output Set in FEMAP can only contain the Nonlinear OR the “Regular” stresses/strains, not both. Checking this option will always read in the Nonlinear stresses/strains from the output file of a nonlinear analysis. If this option is not checked, which is the default, FEMAP will bring up a dialog box during the import of results which allows you to choose which stresses/strains to read (Yes = Nonlinear, No = “Regular”).

2.6.2.8 Library/Startup This section allows you to define the default libraries to be used for several different types of entities in FEMAP and define a startup preference. For any of the libraries, you do not have to specify a complete path as long as the file is in a directory which is along your DOS PATH. FEMAP first searches your current directory and then along your path until it finds the file. You can also use the Browse button to search for a specific directory where a FEMAP library file might be found. By using Browse (...), a number of users can share one common set of FEMAP library files, as long as those users have appropriate access and permissions to the directories where the shared library files are located. •The View Library contains views that can be loaded into your model. This file must exist if you are going to use the Load View or Save View buttons in the View Visibility dialog box (Ctrl+Q).

Library/Startup

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The Material, Property, Layup, Connection Property, Function, Analysis, and Format libraries are files which contain data that can be accessed via the Save and Load buttons on the creation (or list) commands. You must specify the name of an existing file if you plan to use the Load option; however, Save will create a new file if one does not currently exist.



The Material Type Definition file contains the dialog box titles as well as the record formats for Other Types of materials. This file can be modified to include additional material types, but modifications are only suggested when accessing FEMAP information from a FEMAP neutral file since dedicated translators such as ABAQUS or LS-DYNA will not recognize these user materials. Materials contained in the mat_scr.esp file installed with FEMAP are supported by the specific dedicated translators.

Deleting Individual Entries and Views from Libraries Any individual entry saved in a Material, Property, Connection Property, Function, Analysis, or Format library in FEMAP can be deleted using the Delete, Library ... commands. These commands allow you to delete entries one at a time from the library currently set in the Library/Startup tab of the Preferences dialog box. Also, any individual view can be deleted from the View library specified in the Library/Startup tab of the Preferences dialog box using the Delete, Library, View command.

Startup Program File/Basic Script/Executable and Custom Tools Custom Tools Path The “Custom Tools Path” allows you to specify a “custom commands and tools” directory to be used every time FEMAP is initialized. You can select the directory by using the Browse button (“...”). FEMAP contains a toolbar called Custom Tools. This toolbar allows you to choose a directory on your machine where you can store all “custom commands and tools”. “Custom tools” can be recorded Program Files (.PRO or .PRG files), FEMAP Basic scripts (usually .BAS files), or “other” executable (for instance, a Visual Basic script compiled into a .EXE file). The Custom Tools toolbar will take any of those file types it locates in the specified directory and automatically place them into a menu structure which drops-down from the Custom Tools toolbar. Note:

If you are using more than 1 or 2 “custom commands or tools”, this saves a great deal of time because in versions of FEMAP prior to 9.3, each command would have to be added to the user commands one at a time and then placed into menus and/or toolbars.

Program Allows you to choose a Program File, FEMAP Basic Script, or “other” executable (for instance, a Visual Basic script compiled into a .EXE file) to run every time FEMAP is initialized or every time the File, New... command is used to create a new FEMAP model. You can select the appropriate file by using the Browse button (“...”) to locate the file in a particular directory. Run for Every New Model When the Run for Every New Model option is checked, FEMAP will run the “Startup Program” every time a new model is created. If unchecked (default), it will only run the “Startup Program” when FEMAP is initialized.

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2.6.2.9 Color This section outlines the options located on the Color tab of the Preferences dialog box.



You can control the default colors for all entities.



The Reset Colors button on this dialog box changes all colors back to the FEMAP defaults.

You can choose the Color Palette to use for these colors. These colors will be used whenever you start a new model. You must save these changes if you want them to have any effect Note:

The Color Palette is stored with the model in FEMAP versions 9.3 and above. This means if you have loaded or altered a Color Palette in a model, that Color Palette will be available when the model is opened and also if the model is transferred into a newer version of FEMAP via a FEMAP Neutral File. You can alter the current Color Palette or load a different Color Palette in any command in FEMAP that brings up the Color Palette dialog box (i.e., Modify, Color, Node).

You can also choose the User Contour Palette which contains the user-defined contour palette colors. This file must exist if you are going to choose the user-defined palette in the View Options command. Note:

The “User Contour Palette” can be specified for each view in a model. This can be done using the View, Options command, PostProcessing Category, Contour/Criteria Levels Option. Clicking the Set Levels... button and then the User Palette... button will allow you to specify the “User Contour Palette”. See Section 8.3.10.4, "User-Defined Contour Palette" for more information about the “User Contour Palette”

Spaceball

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2.6.2.10 Spaceball This section outlines the options located on the Spaceball tab of the Preferences dialog box: The six values in Scale Factors enable you to control the relative sensitivity of each degree of freedom. For example: •if rotation about the screen xaxis is slow, increase the x rotation scale factor. If you increase it too much, the motion in that degree of freedom will not be smooth. •if zooming is too fast, reduce the z translation scale factor. If you reduce the value too far, it will take a long time to zoom in or zoom out in the model Sometimes, when moving the spaceball in one degree of freedom, it is difficult to prevent motion in another degree of freedom. On the 3Dconnexion driver dialog, you can switch Dominant Axis on. This suppresses all motion except the largest. If this is off, you can effectively control the same thing with the Directional Sensitivity slider. Moving the slider to the right makes the largest axes dominant and moving the slider to the left allows all the axes to effect the motion. The default position is in the middle. Print Debug Messages If you turn this option on, FEMAP will write print debug messages to the Messages window. FEMAP Support may request this information to help you resolve a graphics display problem involving a Spaceball device.

2.7 Using File, Recent Models - 1,2,3,4 The four most recently edited model files are listed on the File menu to enable you to more rapidly select them. If you choose one of these files, FEMAP will automatically open this model file, but only after asking you if you would like to save the current model file.

2.8 Exiting FEMAP

Alt+F4

The File, Exit command allows you to leave FEMAP. You will be given a chance to save all current models that are open in this FEMAP session if you have made any changes since your last save. If you have just started a new Untitled model, you will always be asked whether you want to save the model even though it might be empty. If your model is untitled, the standard file access dialog box will be displayed so you can specify a file name for the model.

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3.

Geometry Geometry provides the framework for most finite element meshes. Therefore, it is necessary to have robust tools for creating geometry. FEMAP has the capability to build geometry from simple points to complex 3-D solids. Generally, you can create, copy, or modify geometry. The geometry section of this manual is separated into six main sections, which are listed below. •

Section 3.1, "Creating Points" (on the Geometry menu)



Section 3.2, "Creating Curves"(on the Geometry menu)



Section 3.3, "Creating Surfaces"(on the Geometry menu)



Section 3.4, "Creating Solids/Volumes"(on the Geometry menu)



Section 3.5, "Copying Geometry"(on the Geometry menu)



Section 3.6, "Modifying Geometry" (on the Modify menu)



Section 3.7, "Deleting Geometry" (on the Delete menu)

3.1 Creating Points Points are used for constructing other geometry or finite element data. You may also apply loads and constraints to points, and FEMAP will automatically apply them to nodes attached to the points. Points are similar to nodes in that they are simply located at a specific location. Unlike nodes, however, they are not a finite element entity and are not translated to analysis programs. Instead, they are used for defining geometry. Just as elements reference nodes, curves reference points.

3.1.1 Geometry, Point... ... uses the standard coordinate definition dialog boxes (described in the FEMAP User Guide) to create points. Choosing the Parameters button will display the Geometry Parameters dialog box, where you can set the active layer or point color.

3.2 Creating Curves Curves form the basis from which you can create surfaces, and they can also be generated from surfaces. They reference points to define their location. You can apply loads and constraints directly to curves, and FEMAP will automatically convert them to nodal/elemental values on the attached FEA entities. The Curve section of the Geometry menu has five submenus: •

Curve -Line



Curve - Arc



Curve - Circle



Curve - Spline



Curve - From Surface

3.2.1 Lines Lines are simply straight lines connecting two points. The Geometry, Curve-Line menu is partitioned into three sections: •

The top portion creates lines in the workplane. Any locations that are specified in 3-D space will be automatically projected onto the workplane.

3-2

Geometry



The second section consists of the Rectangle command. This command creates a rectangle in the workplane. It is separated from the commands above because it creates four lines at once.



The bottom portion of the menu contains commands that are used to create lines in 3-D space. These commands do not project the inputs onto the workplane.

3.2.1.1 Geometry, Curve-Line, Project Points... ... creates a line between two locations, which you specify using the standard coordinate definition dialog boxes. Before creating the line, this command projects the coordinates that you specify onto the workplane. Therefore, the line that is created always lies in the workplane. The coordinates are projected along a vector that is perpendicular to the workplane. If you want to create a line between coordinates in 3D space (i.e. not in the workplane), use the Curve - Line, Coordinates comOriginal Coordinates mand.

Workplane

Projected Coordinates

Hint:

You can use this command to create a 2D projected image of 3D geometry. Just set up the workplane so the workplane normal is along the direction that you want to project, and pick the end points of the existing lines (using Snap To Point). New lines will be created in the workplane.

3.2.1.2 Geometry, Curve-Line, Horizontal... ... creates a line, centered around one location. The line is oriented along the X axis of the workplane. The name of this command comes from the fact that in the default XY view, before you reorient the workplane, the workplane X axis is horizontal on the screen. This command uses the standard coordinate definition dialog boxes to specify the coordinates of the required Projected location. The location is automatically projected onto the Coordinates workplane, along a vector which is perpendicular to the workplane. The projected location is used as the center of the line.

Workplane

Yw

The length of the horizontal line in either direction from the center is controlled by the Horizontal/Vertical Line Length parameter. You can adjust this length by pressing the Parameter button on the standard coordinate dialog, and entering a new value prior to defining the center location. Xw

Hint:

Original Coordinates

Since control of the line length is somewhat difficult using this method, but positioning the line is very quick, this method is often used for creating initial construction geometry which you then plan to modify with trim, join or break commands.

3.2.1.3 Geometry, Curve-Line, Vertical... ... works just like Curve - Line, Horizontal, except the line will lie along the workplane Y axis. In the default XY view with the original workplane orientation, this will be vertical on your screen.

Geometry, Curve-Line, Perpendicular...

3-3

3.2.1.4 Geometry, Curve-Line, Perpendicular... ... creates a line in the workplane that is perpendicular to another curve. Three inputs are required for this method, the origin of the new line, the original curve, and a location to specify direction. The origin projected along the workplane normal vector, onto the workplane.

Workplane Projected Base Coordinates Original Curve

Original Coordinates

The total length of the line to be created is based on the Horizontal/Vertical Line Length parameter. You can change the length by pressing the Parameter button to change the length in the Geometry Parameters dialog box. The line to be created will start at the base location (projected onto the workplane), will be oriented perpendicular to the selected curve, and will move in the direction of the location specified as the last input to this command.

Note: If you choose a curve that does not lie in the current workplane, the selected curve will first be projected into the workplane, then the perpendicular to the projection will be determined. The projection method will work fine for lines, but if you choose an arc or circle that is not oriented parallel to the workplane, the resulting line will not be perpendicular to the projection. Rather, it will go through the projection of the original arc/circle center point.

3.2.1.5 Geometry, Curve-Line, Parallel... ... creates a line in the workplane that is parallel to another line. The required input for this command is the original line and an offset distance. The line that you choose does not have to lie in the workplane. If it does not, it will be projected onto the workplane (along the workplane normal) and the new line will be parallel to the projection. The Offset distance is measured in the workplane, perpendicular to the original line. Workplane

Original Curve

When you press OK, you will see the standard coordinate definition dialog box, asking for a Offset Distance location on the side of the original line where measured in the you want the offset curve to lie. Although you workplane can specify the coordinates in any manner, typically the best way is to point at the appropriCoordinates chosen on this ate side of the line, and click with the mouse. side The actual coordinates do not matter, just their relationship to the original curve. The new line will be offset toward the side of the line that you specify.

The length of the new line is identical to the length of the original line that you choose

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Geometry

3.2.1.6 Geometry, Curve-Line, Midline... ... creates a line in the workplane that is the center line between two existing lines. To create a midline, choose two other lines. If they do not lie in the workplane, they will be automatically projected along the workplane normal.

Workplane

Original Curve

The resulting line will lie halfway between the respective end points of the two lines that you Original Curve choose. The length of the midline is determined by the relative positions of the lines you choose.

3.2.1.7 Geometry, Curve-Line, At Angle... ... creates a line in the workplane at a specified angle from the workplane X axis. Initially, you must specify the base coordinates of the line using the standard coordinate entry dialog boxes. The coordinates that you specify are projected onto the workplane, along a vector which is normal to the workplane.

Workplane

θ

Yw

Xw

Finally you specify the angle from the workplane X axis to the line. Positive angles are measured from Positive Angle the positive workplane X axis toward the positive workplane Y axis. Negative angles are measured toward the negative workplane Y axis. The total length of the line to be created is based on the Horizontal/Vertical Line Length parameter. You can change the length by pressing the Parameter Original Coordinates button to change the length in the Geometry Parameters dialog box. Projected Coordinates

3.2.1.8 Geometry, Curve-Line, Angle to Curve... ... is similar to the Geometry, Curve-Line, At Angle command, except that instead of specifying the angle from the workplane X axis, you select a curve, and specify the angle measured from the curve direction. Just like the At Angle command, the first data required is the base location, specified with the standard coordinate entry dialog boxes. The location that you specify is again projected onto the workplane along the workplane normal vector. Next, you choose both the curve to measure from, and the angle from that curve. You can choose any location for this command. It is not necessary for the base location to lie along the curve that you measure. Workplane

Projected Coordinates

Positive Angle

θ Original Curve

Original Coordinates

Geometry, Curve-Line, Point and Tangent...

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If the curve that you select is not a line however, the base location will be projected (in the workplane) onto the curve and the base direction (zero angle) will be along the positive tangent to the curve. θ Projected Coordinates

Tangent to Curve Original Curve

3.2.1.9 Geometry, Curve-Line, Point and Tangent... .... creates a line in the workplane through a point and tangent to a selected arc or circle. The first input for this command is the curve. Use Point of Tangency on this side of Curve

Selected Curve

Projected End Point Coordinates All in Workplane

After selecting the curve, you will see the standard coordinate dialog box. Here you must specify the location of the end point of the line. This defines the end of the line opposite the end that will be tangent to the curve. You can specify any location, but if you specify a location that is not on the workplane, those coordinates will be projected along the workplane normal, to a location which is on the workplane. The only restriction on the end point location is that it must lie outside of the arc/circle that you chose. No tangent can be formed which passes through an interior point to the curve. Finally, the standard coordinate dialog is displayed again. This time you must specify a location on the side closest to the tangent that you want to use. Since there are two tangents that can be formed through any exterior point, this allows you to choose the one that you want. There is no need for precise coordinates in this dialog. You must simply choose a location which is closer to one tangent point than the other; typically, a location on the appropriate side of the circle. For this command FEMAP considers arcs to be the same as circles. That is, you can still form a tangent to a portion of the arc that lies outside of the arc end points. FEMAP ignores the end points, just as if the arc were a full circle. For this reason, you must still choose the “near” location for an arc, even though there may only be one tangent possible that falls within the end points. Note: If you choose an arc or circle that does not lie in the workplane, FEMAP will project the key points of that curve onto the workplane, and use the arc/circle defined by those projected locations to calculate the tangent. If the curve was parallel to the workplane, this will not cause any problems. However, if the curve normal is not parallel to the workplane normal, the resulting tangent will be calculated based on a circle with a projected radius. Use this option carefully.

3.2.1.10 Geometry, Curve-Line, Tangent... ... creates a line in the workplane which is tangent to two arcs or circles. First, you must choose the two curves that you want to use.

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Geometry

You can choose any arcs or circles, but neither curve can lie completely inside the other. If it did, no tangents could be computed. Selected “To Curve”

Pick near here to create tangent as shown

Selected “From Curve”

or, Pick near here to create crossing tangent All in Workplane

When you have selected the curves, FEMAP will ask for a location using the standard coordinate dialog boxes. This location does not have to be specified precisely, but is used to select which tangency points will be used. Typically, as shown above, when you select two circles, there could be four possible tangents - one above, one below and two “crossing” tangents. You must choose a location near the end point on the first curve (the “From” curve) of the tangent that you want to create. The location is not used to compute the tangent. It is just used to select from the four choices.

3.2.1.11 Geometry, Curve-Line, Rectangle... ... automatically creates four lines in the workplane that form a rectangle. The only input required are the coordinates of two diagonally opposite corners of the rectangle. You will specify these locations using the standard coordinate definition dialog boxes FEMAP takes the locations that you specify and projects them, along the workplane normal, to equivalent locations which lie on the workplane. The rectangle is formed from these projected locations. The sides of the rectangle are always oriented along the workplane X and Y axes. Therefore, by changing the orientation of the workplane, you can use this command to create rectangles in various orientations. Workplane

Projected Coordinates

Projected Coordinates Yw

Xw

Original Corner Locations

3.2.1.12 Geometry, Curve-Line, Continuous... ... creates a series of connected line segments between locations specified in three-dimensional space. The specified locations are not projected onto the workplane, however, coordinates that you pick graphically will still always be located in the workplane. This is usually the best command to use whenever you must create a boundary, since it requires very little input.

Geometry, Curve-Line, Points...

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The standard coordinate definition dialog boxes are used to specify the line segment end points. The first line will be created after you specify the second end point. Then, another line will be created after each additional location that you specify. These lines will connect the previous location to the one that you just specified. As each line is created, it will appear in your graphics windows.

End point Locations

Optionally create line to close

You can continue to specify coordinates and create lines for as long as you like. There is no limit on the number of lines you can create in a single command. When you are done, press Cancel to stop creating lines. If you press Cancel after having created two or more lines, you will be asked whether you want to close the lines. If you choose Yes, a final line will be created joining the last location that you specified to the first location - thus creating a closed polygon. Hint:

If the lines that you need to create are not coincident at their end points, use the Geometry, Curve-Line, Coordinates command instead of this command.

3.2.1.13 Geometry, Curve-Line, Points... ... creates a single line between two existing points. Unlike the other line creation commands, this command can only be used when you already have point entities that you want to connect. The primary use for this command is to connect end points of other curves. To request the points that you want to connect, you can enter the point IDs or choose them with your mouse, but the points must already exist. Since the new line simply connects these existing points, it does not lie in the workplane, unless both points you select happen to be located in the workplane.

Point

Point

3.2.1.14 Geometry, Curve-Line, Coordinates...

F9

... creates a single line in three dimensional space between two coordinate locations that you specify using the standard coordinate definition dialog box. This command is very similar to the Geometry, Curve-Line, Continuous command, except that it requires two end points for each line that is created. You should use this command when you have a series of lines to create, but the lines are not connected at their end points.

3.2.1.15 Geometry, Curve-Line, Offset... ... creates a line offset, in three dimensional space from another line. You first select the line from which you want to offset. You may only choose lines for this command.

Offset along this vector

Original Curve

When you have selected the existing curve, you will see the standard vector definition dialog box. The vector that you specify will be used to compute the offset location of the new line. You do not have to specify the base of the vector at either end point, nor at any other specific location. The vector components are simply used to offset the end points of the original line. The length of the vector that you specify will be the offset distance.

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Hint:

Geometry

If you need to offset multiple curves along the same vector, including curves that are not lines, use the Geometry, Copy, Curve command instead.

3.2.1.16 Geometry, Curve-Line, Vectored... ... creates a three dimensional line using the standard vector definition dialog boxes. This command gives you access to the many special vector definition methods (along axis, components, normal, bisect,...) when creating lines. The line that is created will go from the base to the tip of the vector that you specify. Even if you just use the basic vector definition methods, like “locate”, when you choose the base and tip of the line graphically, you have the benefit of seeing the line/vector dynamically drawn with the cursor before you choose the end points.

3.2.2 Arcs You may also define circular arcs with FEMAP by using the commands under the Geometry, Curve-Arc menu. This submenu is broken into two sections. The commands at the top of the menu (above the separator line) all create arcs which lie in the current workplane. The other commands can create arcs anywhere, including in the workplane. All of the methods can be used to create equivalent arcs. The various commands are merely for convenience in specifying the input.

3.2.2.1 Geometry, Curve-Arc, Center-Start-End... ... creates an arc in the workplane by specifying the location of the center and two end points of the arc. The standard coordinate definition dialog boxes are used to define all three locations. The locations that you specify are first projected onto the workplane along the workplane normal, and are then used to define the arc. As shown in the figure, the center location and start point are used to define the radius of the arc. The end point does not have to lie on the perimeter, but the arc will terminate along the line that goes from the center to the end point.

End point Yw

Start point radius

Center of Arc

All in Workplane

Xw

End point Start point Xw Center of Arc

All in Workplane

Yw

The arc will always be created in a counterclockwise direction in the workplane. That is, the arc will go from the start point, in the direction from the workplane X axis toward the workplane Y axis. As shown in the figure, if you reverse the workplane normal, the same start and end points create complimentary arcs. Similarly, just swapping the start and end points produces the same results.

3.2.2.2 Geometry, Curve-Arc, Radius-Start-End... ... creates an arc in the workplane by specifying two end points and the desired radius. To use this command you must first specify the starting and ending locations of the arc using the standard coordinate entry dialog boxes. You can specify any three-dimensional locations, but they will be projected onto the workplane, along the workplane normal.

Geometry, Curve-Arc, Angle-Start-End...

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After specifying the end points, you will be asked for the radius. If you specify a positive radius, the resulting arc will always have an included angle less than 180 degrees. A negative radius will choose the complimentary or major arc (always greater than 180 degrees). This command creates arcs that go in a counter-clockwise direction (relative to the workplane axes) from starting to ending points. The figure shows several possibilities: All in Workplane Start point

Yw

End point

Positive Radius

Xw

End point

Negative Radius

Start point

Negative Radius

Start point

End point

Positive Radius

End point

Start point

Reversing the direction of the workplane normal has the same effect as swapping the end points, as shown in the figure.

3.2.2.3 Geometry, Curve-Arc, Angle-Start-End... ... creates an arc in the workplane by specifying two end points and the included angle of the arc that connects them. This command works just like the Geometry, Curve-Arc, Radius-Start-End command, except that you specify the included angle instead of the radius. The shape and orientation of the arc to be created follows the convention shown for the Radius-Start-End method. If you specify a positive angle, the arc will go in a counterclockwise direction (relative to the workplane X and Y axes) from the start to the end point. A negative angle goes in a clockwise direction. This agrees with the normal conventions for two-dimensional polar coordinates.

All in Workplane Start point

Yw

End point

Positive Angle End point Xw

End point

Negative Angle

Start point

End point

Positive Angle

Start point

Negative Angle

Start point

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Geometry

3.2.2.4 Geometry, Curve-Arc, Angle-Center-Start... ... creates an arc in the workplane by defining the location of the center, the starting location and the included angle. If the locations that you specify do not lie in the workplane, they will be projected along the workplane normal to new locations that are in the workplane. This command is very similar to the Geometry, Curve-Arc, Angle-Start-End command. Instead of specifying an ending location, however, you specify the center. The arc radius is automatically determined from the distance between the center and starting locations. The end point is determined by rotating the start point through the specified angle. If you specify a positive angle, the arc will be drawn in a counter-clockwise direction relative to the workplane axes. A negative angle will create a clockwise arc. For an example of this convention, refer to the figure for "Geometry, Curve-Arc, Angle-Start-End...".

3.2.2.5 Geometry, Curve-Arc, Chord-Center-Start... ... creates an arc in the workplane by defining the location of the center, a starting location and the length of the arc chord. The standard coordinate definition dialog boxes are used to define both the center and starting locations. Both of these locations will be projected onto the workplane, if required. The relative positions of these projected locations determines the arc radius. All arcs created by this command are drawn in a counter-clockwise direction (relative to the workplane XY axes). If you specify a positive chord length, the arc will always have an included angle less than 180 degrees. Specifying a negative angle creates a complimentary arc with an included angle that is larger than 180 degrees. By definition, the chord length must always be shorter than twice the radius (the distance from the center to starting point). Center Center

All in Workplane

Start point

Yw

Chord Length Positive Chord

Chord Length

Start point

Negative Chord

Xw

3.2.2.6 Geometry, Curve-Arc, Points...

Ctrl+F9

... creates an arc which passes through three locations on the perimeter. This arc does not have to be in the workplane. It will be drawn through any three locations that you define. Other Location End Start

The standard coordinate dialog boxes will be displayed three times during this command. The first coordinate is used for the start of the arc, the second for any point along the arc, and the third for the ending location. Since the arc is drawn from the start, to the middle, to the ending locations, there are no clockwise/counter-clockwise conventions. The direction is simply based on the relative positions of the three locations.

3.2.2.7 Geometry, Curve-Arc, Center and Points... ... creates an arc which is defined by its center, start and ending locations. The arc created by this command does not have to lie in the workplane. It is oriented by the locations that you define. The standard coordinate dialog boxes will be displayed four times during this command. The first three coordinates are used to define the center, starting and ending locations. The arc radius is defined by the distance from the center to the start location. The ending location is used to determine the included angle. The end of the arc will always lie

Geometry, Curve-Arc, Start-End-Direction...

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along the line connecting the center and the ending location that you specify. Since the arc radius is constant however, the arc will not necessarily end at the location you specify. The only time it will end exactly at that location is if the distance from the center to the end is identical to the distance from the center to the start. Center Start

Other Location

Other Location End

Start

Center

End

After you specify the first three locations, the standard coordinate dialog box will be displayed a fourth time. The fourth location can be specified anywhere, but it is used to determine which of the two possible arcs will be created. Since there is no clockwise/counter-clockwise convention for this three dimensional arc, the arc will be drawn in the direction from the start to the end that causes it to pass nearest to this fourth position.

3.2.2.8 Geometry, Curve-Arc, Start-End-Direction... ... creates an arc that is defined by two end points and the tangent vector at the starting location. This arc does not have to lie in the workplane. It is oriented by the locations of the end points and the direction of the tangent. The two end points are defined first, using the standard coordinate dialog boxes. There is no restriction on the positions of these End coordinates, but they must not be coincident. Finally, the standard vector definition Tangent dialog boxes are used to define the starting Tangent Vector can be located tangent. The tangent vector can be defined End Start anywhere relative to any convenient location. It does not have to be based at the starting location of the arc. Only the direction of the vector is used to define the initial tangent direction of the resulting arc. Start

Note: The only restriction on the vector direction is that it must not be parallel to the line connecting the starting and ending locations. If it were, it could not be an arc tangent. Similarly, it is relatively unusual to choose vectors that are very close to being parallel. They will result in arcs with very large radii.

3.2.3 Circles There are several methods of creating circles in FEMAP. The Geometry, Curve-Circle submenu is partitioned into two sections. The commands at the top of the menu (above the separator line) all create circles which lie in the current workplane. The other commands can create circles anywhere, including in the workplane. All of the methods can be used to create equivalent circles, the various commands are merely for convenience in specifying the input.

Points on a Circle No matter which command is used, five points will be created for each circle - one at the center, one at the starting location on the perimeter, and three more every 90 degrees around the perimeter from the starting location. The radius of the circle is determined by the distance from the center to the starting location. The other points are merely for your convenience in defining other geometry. For example, you can easily snap a cursor selection to any of these locations by choosing the Snap To Point method. If you are modifying (moving, rotating...) points, you must be careful. If you do not move all of the points for each curve, the circle radius may change, and the other points will no longer lie on the perimeter. In general you should always use the curve modification commands, rather than the point modifications if you wish to preserve the original geometry.

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Geometry

3.2.3.1 Geometry, Curve-Circle, Radius... Start radius

Yw

Center

Xw

... creates a circle by specifying the two end points of a radius. That is, a location at the center and one on the perimeter. This circle will always lie in the workplane. If you specify coordinates that are not in the workplane, they will be projected onto the workplane prior to defining the circle. The standard coordinate definition dialog boxes will be displayed twice. First for the center, then for the starting point. As shown in the figure, the points on the perimeter are oriented relative to the line between the center and starting locations. They are not based on the work-

Other points

plane X or Y axes.

3.2.3.2 Geometry, Curve-Circle, Diameter... Other point

Start of diameter

diameter

Yw

Xw Other point

End of diameter

... creates a circle in the workplane, by specifying two locations at opposite ends of a diameter. This command is similar to Geometry CurveCircle Radius, but instead of defining the center, you specify a point on the opposite side of the perimeter. Again, this command projects the locations that you specify onto the workplane before creating the circle.

3.2.3.3 Geometry, Curve-Circle, Center... ... creates a circle in the workplane by specifying a location at the center, and the length of the radius. The center location is defined using the standard coordinate definition dialog boxes. The location that you define is first projected onto the workplane before being used as the center of the circle. Positive Radius Yw

radius

Start

Xw

Center

Negative Radius

Unlike the Curve-Circle Radius and Diameter commands, this command does depend on the orientation of the workplane X and Y axes to orient the circle. The starting location is always positioned in the direction of the positive workplane X axis relative to the center. If you specify a positive radius, the first point (at 90 degrees along the circle) is located in the direction of the positive workplane Y axis. If you specify a negative radius, it is located in the

direction of the negative workplane Y axis.

3.2.3.4 Geometry, Curve-Circle, Two Points... Positive Radius Other location

Negative Radius

Starting location radius Other location

Yw

Xw

Starting location

radius

... creates a circle in the workplane which passes through two locations and has a specified radius. This command is similar to the Geometry, Curve-Circle, Diameter command in that you first specify two points on the perimeter of the circle using the standard coordinate dialog boxes. In this case, however, the locations are not at opposite ends of a diameter. The first point is still used as the start of the perimeter.

Geometry, Curve-Circle, Point-Tangent...

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The second point is used to orient the circle, but does not determine the radius/diameter. Rather, an additional dialog box is displayed which asks for the length of the radius. As shown, if you specify a positive radius, the center of the circle will be chosen so that the circle will be drawn in a counter-clockwise direction relative to the workplane X and Y axes. A negative radius chooses the center so that the circle is drawn in a clockwise direction.

3.2.3.5 Geometry, Curve-Circle, Point-Tangent... ... creates a circle by specifying a center location and choosing a tangent arc, circle or line. This command always creates circles in the workplane. You specify the center coordinates using the standard coordinate dialog boxes, but they will be projected onto the workplane before being used to define the circle. Original Curve

Center Yw Start automatically positioned at point of tangency

Xw

Next, you will be prompted for the curve ID. This allows you to choose the curve that will be tangent to the new circle. You can choose any line, arc or circle. You cannot choose a spline. No matter what curve you choose, it will be considered to be infinite when computing the tangency. That is, lines will extend to infinity, and arcs will be considered to be full circles.

If you choose an arc or circle, there would be two possible points of tangency. This command will always choose the one that is closest to the center of the new circle. You cannot use this command to create a circle which envelops another circle. You can, however, create circles which are tangent to either the interior or exterior of another arc or circle. The starting point of the new circle will always be located at the point of tangency.

3.2.3.6 Geometry, Curve-Circle, Tangent to Curves... ... creates a circle, of a specified radius, in the workplane which is tangent to two other curves. Only the dialog box show here is required for this command.

The circle to be created will be tangent to the two curves that you select. If you are choosing two lines, make certain they are not parallel. The radius can be any value, but must be large enough to make the double tangency possible. For example, if you are choosing two circles that are separated by 10 inches, a 1 inch radius cannot possibly be tangent to both. Pick Curve 2 graphically in this quadrant to create this circle Curve 2 Curve 1

Yw

Xw

Other possible tangent circles. Center Near chooses which one will be created

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Geometry

The coordinates that you specify for With Center Near are simply used to choose from among the several possible tangent circles that could be created. Only the circle which has its center closest to the location that you specify will be created. For convenience, you can change the coordinate system in which this location is specified. If you are using your mouse to select the curves graphically, the With Center Near coordinates will automatically be set to the location where you choose the second curve. If you are careful, when you select this curve, you will not have to respecify any additional center coordinates. Note: You can choose any type of original curves for this command, however, they should lie in the current workplane. If they do not, they will be projected onto the workplane prior to computing the tangency and you may not get the results that you expected. Similarly, because of inaccuracies in computing offset splines (which are used in the tangency calculations), you may find that if you choose one or more splines, the resulting circle does not actually touch the spline. For this reason, this command is not recommended when you are working with splines.

3.2.3.7 Geometry, Curve-Circle, Concentric...

radius Yw

Xw

... creates a circle in the workplane which has the same center as another circle or arc. You can specify any radius for the new circle. This is a very quick method for creating a series of circles which have the same center. Simply select the curve and input the radius. The curve must be an arc or circle. The starting location of the new circle will be in the same direction from the center as it is Original for the original curve that you select. Circle

3.2.3.8 Geometry, Curve-Circle, Points on Arc... Other Location Start

... creates a circle which passes through three specified locations. This command is just like the Geometry, Curve-Arc, Points command, except that it creates a full circle rather than an arc. The resulting circle does not have to lie in the workplane, it is completely oriented by the three locations that you specify.

Final Location

3.2.3.9 Geometry, Curve-Circle, Center and Points... Other Location Start Center

starting locations.

... creates a circle specified by its center, a starting location on the perimeter and one other location. This command is just like the Geometry Curve-Arc Center and Points command, except that it creates a full circle rather than an arc. In addition, one less location is required since there is no end point for a circle. The Other Location does not have to lie on the perimeter of the circle. It is only used to determine the positive direction around the circle from the starting location. The radius of the circle is determined from the distance between the center and

Splines

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3.2.4 Splines FEMAP has the capability to produce splines containing from between four to 110 points. Splines created in FEMAP with four points will be stored as cubic Bezier curves. Splines created through the Ellipse, Parabola, Hyperbola, Equation, Tangents, and Blend suboptions will automatically contain four points and be stored as cubic Bezier splines. Splines created with the remaining commands with more than four points will be stored as BSplines. In addition, Non-Uniform Rational B-Splines (NURBS) can be imported through the IGES translator. Splines are created from their control points. The actual curve passes through the first and last control point, but does not pass through the intermediate points. FEMAP does have methods which allow you to input a spline based upon points on the spline, however, FEMAP will use these points to calculate the control points, and then store the spline with its control points. The control points of a spline determine the direction of the spline. Starting Tangent

Final Control Point

First Control Point Final Tangent Intermediate Control Points

Final Tangent Starting Tangent

In addition to direction, distance between control points influences curvature of the spline. The further the control point is pulled from the previous control point, the more the spline is “pulled” toward the intermediate point, and the curvature is increased.

Displaying Splines Splines are computed internally with full double precision accuracy. For display purposes however, splines are displayed as a series of line segments. If you want to change the accuracy of the display, either to make it more accurate (but slower), or less accurate (but faster), use the View Options command. Choose the Tools and View Style list, and the Curve and Surface Accuracy option. Then set the Max% Error value. A smaller number makes the display more accurate. The Geometry, Curve-Spline submenu is partitioned into three sections: splines in a workplane, splines from analytics (also in the workplane), and splines in 3-D space. Each of the commands on these menus are discussed below

3.2.4.1 Geometry, Curve-Spline, Project Control Points... ...creates a spline in the workplane specifying the location of the control points. The standard coordinate definition dialog boxes will be displayed as many times as required (up to 110 times) to allow you to define the control points. If you create a spline with four points, it will be a Bezier spline. More points will force the curve to be a B-spline. If the locations you choose are not in the current workplane, they will be projected onto the workplane before the spline is created. Note: The Cancel button on the dialog box is utilized to both cancel the creation of the spline, as well as create it. If less than four points have been chosen, the Cancel button will enable you to terminate the process without creating a spline. Once four points have been defined, however, the Cancel button is used to terminate input of more points and a spline is created. If you make an input error after four points have been defined, you cannot cancel the procedure without creating the spline. Simply use the Tools, Undo command to remove the spline if it is inaccurate. This is true for all procedures that enable you to create B-splines.

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Geometry

3.2.4.2 Geometry, Curve-Spline, Project Points... ... is similar to the Geometry, Curve-Spline, Project Control Points command, except that instead of defining the control points, you specify four or more points on the spline. The control points are computed automatically so that the spline passes through the points that you specified. The standard coordinate dialog boxes are used to define the points, and the locations are, as usual, projected onto the workplane. The spline will go through the points in the order that you define them - from first to last. Computed Control Point First Point

Fourth Point

Second Point Third Point

All in Workplane

Computed Control Point

This command is typically used to create two-dimensional splines to fit a curve through known locations. It lets you precisely control points to lie along the spline. Some care should be taken, however, when choosing those points. If you choose points that are extremely close together, it can result in control points at great distances from the spline.

3.2.4.3 Geometry, Curve-Spline, Ellipse... ... creates four splines, in the workplane, that together form an ellipse. Each spline represents one quadrant of the full ellipse. When you choose this command you will be asked for the center location using the standard coordinate dialog boxes. The center will be projected onto the workplane whenever necessary. Next, the standard vector definition dialog boxes are used to specify the orientation of the principal axis from the center, as shown in the figure The base location and length of the axis vector are unimportant, only the orientation is used. You must be careful to specify a vector that is not perpendicular to the workplane, since the vector must be projected onto the workplane. It is the projection that orients the ellipse. Principal Axis Vector can be major or minor axis. Other Radius Vector Radius All in Workplane

Finally, you will specify the two radii. The first, or Vector Radius, is the radius of the ellipse along the vector that you just specified. The other radius is the radius along the other principal axis of the ellipse. If you specify equal radii, the splines will approximate a circle. Note: Since the underlying mathematics of the spline are based on a parametric cubic equation, the resulting splines cannot precisely represent a circle or ellipse. For most FEA analyses, however, the approximation is close enough. Given the four spline layout created by this command, with equal radii, the maximum deviation from a true circle would be 0.027% of the radius. If this is not close enough, use arc/ circle commands to create precise geometry.

3.2.4.4 Geometry, Curve-Spline, Parabola... ... creates a spline in the workplane that is one side of a parabola. This command requires three sets of coordinates. Each location is defined using the standard coordinate dialog boxes, and is projected onto the workplane before being used to create the spline.

Geometry, Curve-Spline, Hyperbola...

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The first location is the vertex of the parabola. The spline will start from this location. The next location Focal Direction is the focus of the parabola. These coordinates (along with the vertex) are used to determine the Specified End Point Focus focal length and focal direction of the parabola. Neither the spline nor its control points are actually Vertex located at the focus. For reference, however, an extra All in Workplane point is created at this location. The final location is an approximate end for the spline. These coordinates do not have to be specified precisely. They do not have any impact on the shape or orientation of the parabola, they simply define where you want the parabola to end. Hint:

This command always creates a parabola which extends completely to the vertex. If you need some other segment of a parabola, you can still use this command to create a basic curve, then use the Modify, Trim command to cut away the portions that you do not need.

Note: Even though the spline is defined by a parametric cubic equation, the representation of a parabola is precise. Unlike ellipses and hyperbolas, there is no deviation from a true parabola.

3.2.4.5 Geometry, Curve-Spline, Hyperbola... ... creates a spline in the workplane that is one side of a hyperbola. The first input required is the location of the vertex of the hyperbola. The standard coordinate diaVector toward Focus log boxes are used to specify this location. The spline will start from this location. The standard vector dialog boxes are then used to define a vecSpecified tor toward the focus. The origin and magnitude of Asymptote Angle End Point Vertex this vector are not important, only the direction is used to orient the hyperbola. Next, you must specify the vertex height and asymptote angle, as shown in the figure. These values determine the All in Workplane shape of the hyperbola. Finally, an approximate end for the spline/hyperbola is required. These coordinates do not have to be specified precisely. They do not have any impact on the shape or orientation of the hyperbola, they simply define where you want the curve to end. Vertex Height

Asymptote

Hint:

This command always creates a hyperbola that extends completely to the vertex. If you need some other segment of a hyperbola, you can still use this command to create a basic curve, then use the Modify, Trim command to cut away the portions that you do not need.

Note: Since the underlying mathematics of the spline that this command creates is a parametric cubic equation, it cannot precisely represent a hyperbola. For most finite element applications, however, the deviations are acceptable. The exact deviations are dependent on the geometry specified, but even extreme cases will be very accurate.

3.2.4.6 Geometry, Curve-Spline, Control Points... ... creates a spline by specifying its control points. This command is exactly like the Geometry, Curve-Spline, Project Control Points command, except that the locations that you define are not projected onto the workplane. Therefore, the spline created by this command does not necessarily lie in the workplane, and in fact may be nonplanar.

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Geometry

3.2.4.7 Geometry, Curve-Spline, Points... ... creates a spline by specifying four points along the spline. This command is exactly like the Geometry, CurveSpline, Project Points command, except that the locations that you define are not projected onto the workplane. Therefore, the spline created by this command does not necessarily lie in the workplane, and in fact may be nonplanar.

3.2.4.8 Geometry, Curve-Spline, Equation... ... creates a spline by specifying the coefficients of its parametric cubic equations. This is a rather cumbersome way to create a spline, but provides complete control over the resulting curve. The parametric equations are shown in the dialog box with blanks for the coefficients. Leaving a coefficient blank effectively eliminates that term from the equation. If you leave all coefficients for one of the x, y or z equations blank, the spline will be planar in the corresponding global plane.

3.2.4.9 Geometry, Curve-Spline, Tangents... ... creates a cubic Bezier spline by specifying starting and ending tangent vectors. The standard vector creation dialog box is displayed twice so you can define the two vectors. For this command it is important to define the vector direction, location, and magnitude. The base location of each vector is used as the starting and ending locations of the spline. The direction and magnitude are used to position the intermediate control points. Starting Tangent Base of vector is end point of spline

Magnitude and direction of vector defines intermediate control points

Final Tangent

This method can be very powerful when you use the advanced vector definition (tangent, bisect, normal...) methods.

3.2.4.10 Geometry, Curve-Spline, Blend... ... creates a spline that connects and blends the ends of two existing curves. The resulting spline will be tangent to the respective ends of the two curves. This command offers only limited control of the interior of the spline but enforces both connectivity and tangency at the end points. Here you select the two curves, and two coordinate locations. The coordinate locations are only used to determine which end of each curve that you want to select. You do not have to specify precise coordinates. In fact, if you choose the curve graphically the coordinates will be automatically specified to the location you were pointing to when you picked the curve. Therefore, be sure to point near the end of the curve that you want to use when you make the selections.

Geometry, Curve-Spline, Midspline...

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The other required input is the Blend Factor. This factor is the only control over the interior shape of the spline. By specifying a larger number, the spline will closely follow the ending tangents for a larger distance, typically causing more curvature near the center of the spline. Smaller numbers make the tangency weaker, therefore, most of the curvature will be near the ends of the spline. The figure shows some possibilities. Blend Factor = 1.0

Blend Factor = 1.5

Blend Factor = 0.5

If you specify a blend factor which is too large, or too small, you can create splines that have

loops, or extreme curvature.

3.2.4.11 Geometry, Curve-Spline, Midspline... ... creates a spline which is midway between two curves. Any two curves can be used for this command. The only input required is the two curves. FEMAP will automatically create a spline which is midway between the two curves.

3.2.4.12 Geometry, Curve-Spline, Offset... Offset to this side of original Original Curve Offset

... creates a spline that is offset from another spline along a direction parallel to the workplane. This does not necessarily create splines in the workplane - it just offsets them in a direction which is parallel to the workplane. The offset is however a planar offset. Three dimensional (nonplanar) splines cannot be offset in multiple directions along their length. The first input required for this command is the ID of the original curve (which must be a spline), and the offset distance.

Then, using the standard coordinate dialog box, you will specify a location on the side of the original curve (relative to the current workplane) where you want the offset curve to be created. The coordinates are not important, just which side of the original curve you want. Note: Cubic Bezier splines (ones with only four points) cannot be offset precisely, due to the underlying mathematics. You will find that the offset curve is not a constant distance from the original - sometimes by a significant deviation. This is especially true when the spline is nonplanar. Offset B-splines are modified by adding control points to improve how well the offset spline tracks the original curve. If you need precise offsets, you cannot use splines. Instead, use a series of arcs, since arcs can be offset precisely.

3.2.4.13 Geometry, Curve-Spline, Multiple Curves... ...creates a single spline along multiple, connected curves. The spline points and control points will be created automatically. The only input for this command is a list of curves. The curves must be continuously connected in a single branch loop. The loop does not have to be closed. If possible FEMAP will use exact replicas of the selected curves, and simply create a new continuous curve. If the curves are from mixed geometry engines, or cannot be duplicated, FEMAP will create a FEMAP engine spline that closely approximates the selected curves. Note: Take care to avoid sharp corners, as the resulting spline will not be able to match the geometry correctly.

3.2.5 Curves from Surfaces FEMAP can create curves directly from surfaces. This capability is most often used to create a curve at a specific location on a surface, or at the intersection of two surfaces. You can imprint curves onto a surface to provide additional controls on your meshing procedures. You can define the mesh size on these curves, as well as load or constrain them, just like any other curve in FEMAP. This can be very useful to obtain nodes at specific locations.

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Geometry

This menu is partitioned into three segments. The first portion of the menu contains one command, Geometry, Curves - from Surface, Update Surfaces. This command does not perform any calculations. It simply applies the curve operations in the second and third segments of the menu to the surfaces, and therefore allows imprinting of these curves onto the surfaces. The second and third portions of the menu contain the actual commands. This entire menu of commands is not available in the standard geometry engine.

3.2.5.1 Geometry, Curve - From Surface, Update Surfaces ... toggles the update surfaces between on and off. As mentioned above, this command does not perform any operations directly. It simply controls how the remaining Geometry, Curves - from Surface commands are implemented. If this option is on, which is the default, a check mark will be visible next to the command. When any of the other commands on this menu are then performed, FEMAP will automatically update the surfaces with these curves. This is a very easy method of imprinting curves onto surfaces to customize the meshing procedure. If this option is off, (no check mark), curves are created/manipulated using the surface, but the surface itself is not updated.

3.2.5.2 Geometry, Curve - From Surface, Intersect... ... creates a curve at the intersections of surfaces. The only inputs required for this command are the two solids. FEMAP will create curves at all intersections of these bodies, and update the surfaces at the intersections if this option is on (see Section 3.2.5.1, "Geometry, Curve - From Surface, Update Surfaces").

3.2.5.3 Geometry, Curve - From Surface, Project... ... projects curves onto selected surfaces. You must first select the surfaces, and then select the curve(s) which you want project. FEMAP will automatically project the curves onto the selected surfaces. This command will automatically project normal to the surface.

This command is very useful for imprinting one surface, composed of its bounding curves, onto the surface of a solid. You must have the Geometry, Curves - from Surface, Update Surface on to imprint the curves onto a surface of the solid (see Section 3.2.5.1, "Geometry, Curve - From Surface, Update Surfaces").

Geometry, Curve - From Surface, Project Along Vector...

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3.2.5.4 Geometry, Curve - From Surface, Project Along Vector... ... is identical to Geometry, Curves - from Surface, Project, except you define a vector, using the standard vector definition dialog box, to project along and the curves will be projected onto the selected surfaces as many times as they “find” the surfaces along the projection vector..

3.2.5.5 Geometry, Curve - From Surface, Parametric Curve... ... creates a curve along a surface in either the u or v parametric direction. After selecting this command, you must input a location for the curve, using the standard coordinate definition dialog box. FEMAP will then prompt you to choose between the u direction or the v direction. FEMAP will create the curve along the surface, through the point you input, in the surface direction you chose.

When Update Surfaces is on (see Section 3.2.5.1, "Geometry, Curve - From Surface, Update Surfaces"), you can quickly partition a surface into several segments, which is often useful for loading and meshing purposes.

3.2.5.6 Geometry, Curve - From Surface, Slice... ... requires you to define a plane, using the standard plane definition dialog box, and the solid to slice. FEMAP will create curves which will form the slice through the solid. If Update Surfaces is on (see Section 3.2.5.1, "Geometry, Curve - From Surface, Update Surfaces"), the affected surfaces will also be partitioned by the slice.

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Geometry

3.2.5.7 Geometry, Curve - From Surface, Split at Locations... ... requires you to choose a face to split and then choose a start and an end location to split the selected face with a parametric curve. If Update Surfaces is on (see Section 3.2.5.1, "Geometry, Curve - From Surface, Update Surfaces"), the affected surface will also be partitioned by this command.

3.2.5.8 Geometry, Curve - From Surface, Offset Curves/Washer... ... this command has two “modes”, Washer and Offset Curves. Washer mode should only be used for circular holes on planar surfaces, while Offset Curves is a more “general” mode that can be used for oblong holes, slots, and other “general shapes” on many different types of geometric surfaces.

In either mode, once you click OK in the Define Washer or Offset Curves dialog box, FEMAP will ask you to select the appropriate curves to offset. For Washer mode, only curves that make up circular holes will be eligible for selection and only one curve per hole is required. In Offset Curves mode, all types of curves are eligible for selection and you will want to select all curves to be offset. Clicking Cancel in the Entity Selection - Select Edges dialog box FEMAP will return you to the Define Washer or Offset Curves dialog box. You can now change the mode and size options, then click OK and choose different curves. Click Cancel in the Define Washer or Offset Curves dialog box to exit the command.

Washer Mode In Washer mode you will first want to enter an Offset, then choose whether or not to Save Split Lines. By saving the “split lines”, a line will be created from the end points of each curve in the circular hole to the end points of the new offset curves, which will create an individual surface set-up for mapped meshing..

With “Save Split Lines” Checked

Without “Save Split Lines” Checked

Geometry, Curve - From Surface, Offset Curves/Washer...

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Offset Curves Mode In Offset Curves mode you also enter an Offset, but in this mode you have more choices. Again, you can choose whether or not to Save Split Lines, but this time every selected curve will get an individual surface set-up for mapped meshing.

Without “Save Split Lines” Checked

With “Save Split Lines” Checked

AutoSelect Surfaces will automatically offset the selected curves to ALL of the surfaces connected to those curves. If you would like to choose which surfaces get the new offset curves, uncheck AutoSelect Surfaces. You will be prompted for the surfaces after you have selected the curves and clicked OK. With “AutoSelect Surfaces” checked

With “AutoSelect Surfaces” unchecked and only top surface selected.

When Extend Splits is on, FEMAP will try to extend all offset curves that do not meet up with another offset curve to the closest edge of the surface onto which the curve was offset. In most cases, this should be checked if Save Split Lines has not been checked. With “Extend Splits” unchecked

Curve does not extend Enough to break surface fully.

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Geometry

With “Extend Splits” checked Curve extends to fully break surface

If Update Surfaces is on (see Section 3.2.5.1, "Geometry, Curve - From Surface, Update Surfaces"), the affected surface will also be partitioned by this command. Note: Due to the process used in the Offset Curves mode, the specified Offset can not be larger than the radius of any of the chosen curves. If you receive the message “Error sweeping along edge curves, offset not possible”, try again using an Offset value reduced the by 25%. Also, many times a larger offset can be used in conjugation with the Save Split Lines option turned on.

3.2.5.9 Geometry, Curve - From Surface, Pad... ... requires you to choose a circular edge on a surface to create a “pad” pattern around a hole. The “pad” pattern essentially creates a square a specified distance away from the center of the circular edge and then connects the midpoints of each line of the square to four points on the circle (usually located at 0, 90, 180, and 270 degrees). The distance the curves of the pad are positioned from the selected hole is determined by the Pad Size Factor. The Pad Size Factor uses the diameter of the hole to calculate the size of the pad. If it is set to “1”, the pad will extend out half the length of the diameter (the radius) in all directions. When set to “1.25”, the lines are created 0.625 times the radius in all directions, while “0.75” will create the lines 0.375 times the radius. When Setup Mapped Meshing is on, the four newly created surfaces will automatically have a “Four Corner” mesh approach set on them. For more information on mesh approaches, see Section 5.1.2.15, "Mesh, Mesh Control, Approach On Surface".

Pad Size Factor = 0.75

Pad Size Factor = 1.0

Pad Size Factor = 1.25

The orientation of the “pad” can specified 3 separate ways. Auto Align will simple use a circular curve’s existing points and extend out from them. Vector Align allows you to specify an orientation vector so the pad can be positioned in a certain orientation. Finally, Tangent Align will prompt you to select an additional curve and then create a pad which has an outer edge aligned tangent to the selected curve.

Geometry, Curve - From Surface, Point to Point...

Pads With “Auto Align”

Pads With “Vector Align” (aligned to displayed Vector)

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Pads With “Tangent Align” (Aligned using closest curves)

If only a portion of a hole has been selected (a curve which is not 180 degrees or a full 360 degree curve), you will also be prompted for a Pad/Width Length, select a point as the Pad Center, then specify a Pad Alignment Vector. If Update Surfaces is on (see Section 3.2.5.1, "Geometry, Curve - From Surface, Update Surfaces"), the affected surface will also be partitioned by this command.

3.2.5.10 Geometry, Curve - From Surface, Point to Point... ... creates a parametric curve along a surface by choosing a start point and an end point.

If Update Surfaces is on (see Section 3.2.5.1, "Geometry, Curve - From Surface, Update Surfaces"), the affected surface will also be partitioned by this command.

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Geometry

3.2.5.11 Geometry, Curve - From Surface, Point to Edge... ... creates a parametric curve along a surface by choosing a point and then a curve on the same surface. The location of the newly created point on the chosen curve is created by projecting the chosen point onto the selected curve using the shortest possible distance.

Selected Curve

If Update Surfaces is on (see Section 3.2.5.1, "Geometry, Curve - From Surface, Update Surfaces"), the affected surface will also be partitioned by this command.

3.2.5.12 Geometry, Curve - From Surface, Edge to Edge... ... creates parametric curves along a surface by choosing a single curve (To Curve) on a surface and then a choosing any number of curves also on that surface (From Curves). The locations of the newly created points on the “From Curve” are created by projecting the end points of all the “To Curves” onto the “From Curve” using the shortest possible distance and then joining the two sets of points with parametric curves.

“From Curves”

“To Curve”

If Update Surfaces is on (see Section 3.2.5.1, "Geometry, Curve - From Surface, Update Surfaces"), the affected surface will also be partitioned by this command.

Creating Surfaces

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3.3 Creating Surfaces There are several types of surfaces in FEMAP. The following table summarizes those types, and the commands that create them. Surface Type Boundary

Bilinear Ruled

Revolution

Coons

Bezier

Face

Commands

Characteristics

Sketch, Boundary Surface

Bounded by curves on all edges and can contain voids (holes). Typically used for planar meshes and as basic framework for solid model generation. Corners, Edge Curves, Bounded by lines on all edges. Surface is defined by Plane bidirectional linear interpolation between the edges. Edge Curves, Ruled, Bounded by any curves on two opposing edges, with Extrude, Sweep, Cylin- lines joining the end points. Surface is defined by linear interpolation between the two edge curves. der Revolve, Sweep, Cylin- Surface is defined by revolving a curve through some angle. Original defining curve can be of any der, Sphere type. Edge Curves Surface bounded by three or four curves of any type. Interior is defined as a bidirectional cubic interpolation. Aligned Curves Surface defined by 16 control points (arranged in a four by four array). The surface only passes through the control points at the corners. all of the above Complex trimmed surfaces obtained from solid model Boolean operations or imported from IGES files.

You do not have to worry about which type of surface is being created. All surfaces can be used equally well for meshing or other purposes. This information is just provided so you can understand the various methods that are being used. Note: When you use these commands in the FEMAP standard geometry engine to create surfaces, you cannot perform Boolean operations on these surfaces. They can be used for meshing as well as creating volumes, but not for intersection or Boolean solid operations.

Surface Parameters When you are creating surfaces, you will see numerous dialog boxes with a Parameter button. Choosing this button lets you set various options which control the surfaces that you will create. You will see the Geometry Parameters dialog box All of the parameters of interest are in the Surface section. You can choose the ID of the next surface to be created, although it is usually not of great concern. You can also choose a color for the surface - either by typing its number or by pressing the Palette button and choosing from the standard palette. If you do not set a color, you can always change the color later with the Modify, Color, Surface command

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Geometry

Surface Divisions The final surface parameters are the number of divisions. When surfaces are displayed, intermediate curves are drawn to show you the shape of the interior of the surfaces. They have no impact on the actual shape of the surface or on the position of any location on the surface, they are purely for display purposes. By changing the number of divisions, you will control how many curves will be drawn for each surface. Typically, very curved surfaces will need more divisions, planar surfaces need fewer. You can independently control the divisions along the two parametric surface directions (shown as s and t). By setting the parameters to different values in the two directions, you can very quickly see (by counting the number of curves) the orientation of the surface directions. This can be of assistance when setting mesh sizes on surfaces. You can modify the number of divisions on surfaces that you have already created using the Modify, Update Other, Surface Divisions command.

Commands There are four commands/menus in the surface area of the Geometry menu. The first two, Sketch and Boundary Surface, create a boundary surface, while the third listing, surfaces, is actually a submenu of several commands for creating surfaces. Each of these commands will be discussed in more detail below. The major difference between a boundary surface and a surface is that a boundary surface is typically planar, while a surface is typically 3-dimensional. Also, surfaces can be readily mapped mesh, while boundary surfaces require a “free-mesher”. The forth category is Midsurface which contains a number of commands to create and modify midsurface geometry created from solids.

3.3.1 Sketch The Sketch command provides a quick method to create boundary surfaces. This command essentially combines the capability of the individual geometry creation commands under the Geometry menu with the Geometry, Boundary Surface command. When you first select this command, the following window will appear, and the right hand toolbar will be switched to one of the geometry toolbars. You can then use the toolbars, as well as the menu commands to create geometry. Once you create the geometry for your boundary surface, simply press Finish Sketch on the above Window, and FEMAP will automatically create a boundary surface from the geometry you just created. Until you select Finish Sketch, the individual geometry which you just created contains no association between the geometric entities. If you press Cancel, the geometry you just created will remain, but a boundary surface will not be created. If you have accessed this command through the Solids toolbar, you will also have the option to Extrude or Revolve. When you select one of these options, FEMAP will automatically create the boundary surface and then move to the Solids Extrude/Revolve menu.

3.3.2 Boundary Surfaces... There are two basic ways to create boundary surfaces - by selecting the boundary curves, or by combining existing solid faces. The following section describe these methods.

3.3.2.1 Geometry, Boundary Surface, From Curves...

Alt+F11

is used to create boundaries that will be used with the Mesh, Geometry, Surface command. A boundary is a series of connected curves that enclose an area that you want to mesh. A boundary is most often used to define planar areas for meshing that have more than four sides, and which are easier to define as curves than as faces of solids.

Geometry, Boundary Surface, From Curves...

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Choosing Curves for a Boundary To define a boundary you simply select the curves that you want using the standard entity selection dialog box. The curves that you pick must form one or more closed loops, that are connected end-to-end. There cannot be any gaps, or multiple connections (branches) in the loops. In addition, the curves should never cross or intersect. If you are selecting multiple loops, one of the loops must completely contain all of the others. That is, the other loops are actually representing holes in the outer loop. Good - Single Closed Loops

Bad - Not Closed

Bad - Crossing

The curves do not have to be connected to the same end points, but the end points must be coincident. If they are coincident, the end points will be merged when you create the boundary.

You can select the curves that form your boundary in any order, and you can even “box” or “circle” pick to select all the curves with one selection. FEMAP will automatically order your selections to put them in boundary order. This Bad - Branching, Multiple Loops feature makes it extremely easy to use the area cursor picking methods to choose all of the curves in an area as part of your boundary. You may only select up to 750 curves to define a boundary (including holes).

Adding Holes to Boundaries “Holes” are areas inside the boundary that you do not want this boundary to mesh. They may or may not represent physical holes in your structure. The procedure for defining a hole is identical to that for defining the outer boundary. Simply pick all curves around the boundary of the hole at the same time you are selecting the outside boundary. FEMAP will automatically sort the curves and determine which ones are associated with the hole(s), and which curves form the outer boundary. The same restrictions (single, closed loop...) apply to curves that represent holes. In addition, as you might expect holes cannot overlap (or touch) each other, and they must be totally inside the outer boundary but outside all other holes. You can define as many holes as you like in the boundary, but the total count of all curves that define the boundary and the holes cannot exceed the 750 curve limit. Good, multiple holes

Bad, holes overlap

Bad, holes inside each other

Note: You may also map a boundary onto a surface to obtain a non-planar mesh. For details, see Section 3.6.4.6, "Modify, Update Other, Boundary on Surface...".

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Geometry

Improving Meshing Speed While you can define and mesh very large, complicated boundaries, it is often more productive to break them into multiple smaller pieces. Typically, the boundary mesh command will be able to mesh two smaller boundaries faster than one large one. In addition, you have some extra control over the mesh. The figure shows a typical example. Original Boundary

Two, Simpler Boundaries

Obviously there is a trade-off between the time you might save when making the mesh, and the time it takes to split the boundaries. In general, it is probably worthwhile if you can make the splits by just adding a line or two, like the figure. Otherwise, it is probably faster to mesh the entire boundary. On the other hand, you may still want to add the extra “splits” to get the extra control of the mesh. With the extra curves, you can specify exactly the number of nodes along those splits. Another area of concern is meshing boundaries that are set to Map onto Surface. They can take substantially longer than meshing boundaries that just use the boundary curves. This delay is caused by the extra mapping required to insure that the mesh lies on the surface.

3.3.2.2 Geometry, Boundary Surface, From Surfaces on Solid... Unlike the method of creating boundary surfaces by picking the boundary curves, this command lets you pick adjacent faces of a solid using the entity selection dialog box. You will want to create this type of boundary surface when the surface geometry that you have does not lend itself to creating a good mesh. For example, if you have a number of surfaces that are somewhat skewed, it can result in a mesh that is also skewed, if the surfaces are meshed individually. By combining these surfaces into a single boundary, the mesh can often be improved.

Original geometry showing multi-surface boundary covering four surfaces

Meshed as four individual surfaces

Meshed as Multi-surface Boundary

Geometry, Boundary Surface, Update Surfaces

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When building multi-surface boundaries, it is important to understand how FEMAP will use them in meshing, and the limitations of this method. FEMAP simply takes the surfaces that you select, and uses the enclosing outer curves to form a regular boundary surface. This means that the surfaces that you select must be stitched into a solid. When you select stitched surfaces, the outer boundary curves will form the closed loop that is necessary to create a boundary, and the interior curves can be properly identified. Although the order of your selection is not important, you must select surfaces that create a single region. You cannot select surfaces that are disconnected, or that only join at a single point. If you want to create multiple regions, you must do this in multiple commands. Just as boundaries can have holes, you can select surfaces that surround holes (or simply surround other surfaces that you do not select). When you mesh a multi-surface boundary, FEMAP will mesh it as a planar boundary. It is therefore very important that you do not combine surfaces that contain too much curvature. Best results will be obtained if you combine surfaces that are nearly planar, or have moderate curvature from the “average” plane. There is no checking to prevent you from combining surfaces that have a very large curvature (even greater than 180 degrees), but the resulting mesh quality will surely suffer if you do this. Taken to the extreme, the resulting boundary surface will not be meshable. Although the surface is meshed as a planar boundary, the resulting mesh is projected and smoothed back to the original surfaces. This is much like the Modify, Project Mesh onto Solid command. This is very different than what happens when you use the Modify, Update Other, Boundary on Surface command to attach a boundary to a surface. In that case, the mesh is created in the parametric coordinates of the surface. Any features (curves or surfaces) in the interior of the boundary will simply be meshed over. “Interior” does not, in this case refer to holes which are still on the inside of the boundary. It refers to curves and surfaces that are completely surrounded by surfaces that have been combined. Therefore, if you combine things like fillet surfaces into other adjacent surfaces, they will be meshed over. Some nodes may still lie on the fillet, but there is nothing to retain the basic shape of the fillet. Similarly, if you combine two surfaces that are not tangent at their intersection, the mesh will simply blend over this intersection. There will not be any distinctive break between the surfaces. When you create multi-surface boundaries, FEMAP does several things automatically to help you in later meshing of your surfaces. First, the underlying surfaces that you select are moved to the no-pick layer, and they are feature suppressed. This means that when you later select surfaces or solids for meshing, the underlying surfaces will not be meshed, nor will they even be pickable. If you are creating many multi-surface boundaries, it can sometimes be difficult to tell which surfaces have been selected, and which boundary contains the surfaces. If you go to the Modify, Color, Surface command and choose the boundary surfaces, you will be asked if you want to randomize the colors. Doing this will update the color of the surfaces, in each selected boundary, to be a distinct, but different color.

Working with Unstitched Geometry This command only works with stitched surfaces. If you are unable to stitch the surfaces that you want into a single solid, you will not be able to use this command. You may, however, still be able to accomplish the same meshing result. The first step is to create a boundary using curves around the outside of the region of interest. You may need to make additional curves, if the curves that you have are not joined at their end points. Then, mesh the boundary surface as normal, and go to the Modify, Project Mesh onto Solid command to project the mesh back onto the original unstitched surfaces.

3.3.2.3 Geometry, Boundary Surface, Update Surfaces This command is used when the underlying surfaces that you used to create a multi-surface boundary change due to later modeling operations. When you create a multi-surface boundary, you select the surfaces that you want to represent. At that time, the boundary curves are extracted, and the boundary is created. If you then update the underlying surfaces (slice them, cut a hole in them...) the already defined boundary will not reflect those changes. If you simply select this command, and choose the boundary surfaces to update, the boundaries will be recreated from the current definition of the underlying surfaces, any changes to this point will then be included.

3.3.2.4 Geometry, Boundary Surface, Edit Surfaces ...is used to modify the underlying surface definition of a multi-surface boundary. Choose this command if you want to add or remove surfaces from a boundary that you have already defined via the From Surfaces on Solid command. If you are adding surfaces, the rules for which surfaces can be added follow the same guidelines as if you were defining the surface originally.

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Geometry

3.3.3 Surfaces These commands enable you to create surfaces in the standard geometry engine or the Parasolid geometry engine.

3.3.3.1 Geometry, Surface, Corners... ... creates a surface by defining the location of three or four corners. This command also creates lines along the edge of the surface which connect the corners. Corner 4 Corner 3

The standard coordinate definition dialog boxes are used to specify the corner locations. The locations you specify are not projected in any way, they are simply used to define the surface.

Surface t Direction

Corner 1 Surface s Direction The third corner is the “tip” of the triangle

Corner 2

Corner 3

Surface t Direction Corner 1 Surface s Direction

Corner 2

To create a triangular surface, choose Cancel for the fourth corner (specify a fourth location and choose OK to create a quadrilateral surface). You will then be asked whether you want to make a triangle. Choose Yes to make the surface, No to abort. You can create quadrilateral surfaces with coincident corners to form triangular surfaces, but it is not advisable. When you mesh these surfaces, you will get quadrilateral elements with coincident nodes. If you create proper triangular surfaces, they will automatically mesh with triangular elements at the

“tip”.

3.3.3.2 Geometry, Surface, Edge Curves...

Shift+F9

... creates a surface by choosing three or four existing curves which define its boundaries or edges. The edge curves must be coincident at their respective end points so that they form a continuous, closed boundary. They do not have to physically connect the same points, but if not, they must connect coincident points (which will be merged automatically by this command). The dialog box will be used to choose the edges:

Geometry, Surface, Aligned Curves...

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First, you should choose the desired surface shape - 3 or 4 sided. Then choose the curves that you want to use either graphically or by specifying their IDs. You must choose the curves in order, going around the boundary. You cannot choose the curves in a random order. Curve 3 Curve 4

Curve 2

Surface t Direction Surface s Direction

Curve 1

You can choose any type of curve as an edge. In addition, the curves can be in any orientation, so long as they are all coincident at the end points. The curves do not have to form a planar surface. However, you should not create surfaces with extreme warping, or extreme corner angles. These will be fine as surfaces, but when you apply the finite element mesh you may create very distorted elements. If you do have these extreme types of surfaces, they should be meshed with triangular elements to minimize element distortions.

3.3.3.3 Geometry, Surface, Aligned Curves... ... has two different capabilities based upon the geometry engine in use. You can use this command to create a FEMAP standard geometry engine surface or a Parasolid surface.

Standard Geometry Engine The FEMAP standard geometry engine creates a quadrilateral surface defined by four control curves which are aligned in the same parametric direction. This type of surface gives you control over the shape and curvature of the interior of the surface. It is somewhat more difficult to use however, since the control curves do not actually lie on the surface, they are simply used to control its shape. The only places that the surface touches the control curves are at the corners. You must select the curves in sequential order, along the increasing parametric (surface t) direction. In general, you will want to select splines for this surface, but you can pick any type of curve. If you are going to use other types of curves however, it is often simpler to use one of the other surface commands. Curve 4

Curve 3 Curve 2

Curve 1 Surface s Direction Automatically creates two edge curves

Surface t Direction

As shown, this command creates two additional edge curves that connect the ends of the four control curves. These edge curves do not really define the surface, but are helpful in visualizing the control net for the surface. Be careful, however, if you move one or more of the end points of the control curves, they will no longer lie along the edge curves. This does not hurt anything, but can be confusing visually. In the figure above, you can see how the surface follows the shape of the control curves, but the curves do not lie on the surface. This is especially true for curves which have significant changes in curvature in comparison to the adjacent curves - like Curve 4 above. The actual surface will be blended between the control curves which causes larger deviations in areas of rapidly changing curvature. Note: Since this surface does not coincide with the curves along its edges, it can be difficult to join it with surfaces of other types. It will join properly with another aligned surface that uses the same edge. As shown in the figure, if you have a linear edge (the bottom edge), the surface will coincide with the control curve, so you can join the surface to other surface types.

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Geometry

Parasolid Geometry Engine The advanced geometry engine allows you to fit a lofted surface between a series of curves. It differs from the standard aligned surface in that you can use any numbers of curves to define the surface, and the curves will be on the surface that is constructed. This is a very powerful method to create surfaces with varying curvature simply by defining curves at critical locations. Note: The curves used for this command with the Parasolid engine must always be in the same direction. FEMAP will not automatically reverse the direction. Therefore, if you are having difficulty defining the surface, you should check the direction of the curves by using the View Options, Tools and View Style, Curve and Surface Accuracy option to turn Directions on. This will enable you to confirm that all curves are formed in the same direction. If the directions are not aligned, FEMAP will ask you if you want to try and create a surface through the interpolated points of the curves. You can try this or change the direction of the curves.

3.3.3.4 Geometry, Surface, Ruled... ... creates a quadrilateral surface between two curves. The surface is formed by linear interpolation between corresponding parametric locations along the selected curves. The only inputs for this command are the two curves. After you select the curves, two additional lines are created which join the end points of the original curves. These new lines do not control the surface, but do help to show its boundaries. Curve 2

Surface t Direction

Surface s Direction

Curve 1

Automatically creates edge lines

Ruled surfaces are very easy to create. You can choose any type of curves, in any orientation. They do not have to lie in the same plane. In addition, the resulting surface is usually fairly uniform parametrically and yields very good finite element meshes.

3.3.3.5 Geometry, Surface, Extrude... ... creates surfaces by extruding one or more curves along a vector. Each curve that you choose creates a separate ruled surface. This command allows you to quickly convert a two dimensional profile of curves into three dimensional surfaces. All input for this command uses standard dialog boxes. You select the curves to extrude using the standard entity selection dialog box. You can choose these curves in any order, but it is usually best to choose them in the order of a continuous profile or boundary. When you have selected all of the curves, you will define the vector that you want to extrude them along, using the standard vector definition dialog box. You can choose any vector, but most extrusions should be relatively perpendicular to the original curves. If it is not, some surfaces may be badly shaped for meshing. The same vector is used for all curves that were selected, so if you need to extrude in different directions, you must repeat this command. The vector that you define can be based at any location. Only the vector components and magnitude are used. The components define the direction of the extrusion. The magnitude defines the length of the extrusion.

Geometry, Surface, Revolve...

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As an example, the picture shows a boundary that was extruded. Extrusion direction and magnitude

Surface t Direction Surface s Direction

Selected Curves

Selected Curves

More curves were created (but not shown) at the opposite side of the surfaces. Other curves were created to connect the end points of the original curves to the new curves.

3.3.3.6 Geometry, Surface, Revolve... ... is similar to Geometry, Surface, Extrude, except that instead of extruding curves along a vector, this command revolves them through an angle around a vector - the axis of revolution. Just like the Extrude command, you select the curves to revolve using the standard entity selection dialog box. Next, specify the vector along the axis of revolution using the vector definition dialog boxes. The location and direction of this vector are important; the magnitude is not. Finally, enter the rotation angle: specify the angle through which the curves will be revolved.

Surface t Direction Surface s Direction Axis of Revolution Selected Curves

Selected Curves

Some Special Cases Typically, this command creates four-sided surfaces; however, there are a few special cases. If a curve has one end point that lies on the axis of revolution, a triangular (three-sided) surface will be automatically created. Since all surfaces must have either three or four sides, you cannot revolve any curve that has both end points on the axis of revolution. This limitation includes arcs and splines where intermediate points along the curve do not lie on the axis of revolution. If you want to revolve this type of curve, use the Modify, Break command to split it into two curves, then revolve both of those curves. Another special case arises if the axis of revolution intersects the curve that you are revolving. In this case, the resulting surface will be twisted and effectively unusable for meshing. Although you can create these surfaces, you should avoid this situation.

3.3.3.7 Geometry, Surface, Sweep... ... allows you to create surfaces by moving or sweeping one or more curves along a path defined by other curves. The required input for this command is minimal. You simply select the curves that define the cross section that you want to sweep, using the standard entity selection dialog box. Then with a second entity selection dialog box, you select the curves that make up the path along which you will sweep the cross section.

Selecting the Path Even though you choose it after the cross section, it is important to understand the implications of choosing a path before you define the cross section. The curves that you select for the path must form a single continuous loop either closed (the end is also connected to the start) or open. They must not branch, or have any gaps. They do not have to be connected to the same points, but must have coincident end points.

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Geometry

If, in addition to being coincident, all curves along the path are also tangent at their end points, the sweeping operation will maintain a constant cross section as it traverses the path. On the other hand, if you include nontangent curves, the corners will be automatically mitred to the half angle between the tangents of the curves. This, however, will result in a nonuniform cross section, and in some cases a cross section that is somewhat distorted.

Choosing Splines in the Path You can use any type of curves in the path; however, if you are using the standard FEMAP geometry engine, this command cannot create a single swept surface along a spline. If you choose splines in the path, they will be broken into multiple line segments, and the cross section will be swept along these segments rather than the true spline. This will result in multiple surfaces. You can control the number of line segments by setting the mesh size along the spline prior to sweeping using the Mesh, Mesh Control, Size Along Curve command.

Selecting the Cross Section Just as for the path, you can choose any curves that you want for the cross section. You do have to be aware, however, of the relationship between the path and the cross section. Here are some general rules to follow: 1. The curves in the cross section must be positioned in space at the appropriate location relative to the path. This command simply extrudes and revolves the cross section along vectors which are defined by the curves you select as the path. It is up to you to properly locate the starting position of the cross section. The surfaces created by this command will be located wherever you start the cross section. All offsets from the path to the cross section will act as rigid links as the cross section is swept around a curve. 2. If your path contains arcs, make sure that your cross section does not protrude further than the arc radius to the “inside” of the path. If it does, the resulting surfaces will be twisted as they are swept around the arc. 3. Typically you will want to create the curves for the cross section in a plane that is normal to the ending tangent of the path. If you do not, the cross section that you sweep will be a projection of the true cross section.

Surface t Direction Surface s Direction Axis of Revolution Selected Curves

Selected Curves

4. If the cross section that you choose contains arcs or circles, and your path contains curves that are not tangent to one another, the arcs and circles will be converted to equivalent splines before they are swept. This is not a precise representation, but it is fairly accurate. It is required because of the automatic mitred corners that will be generated between the nontangent curves. The cross section at those corners will no longer be circular, it will be elliptical (which must be represented by a spline).

Geometry, Surface, Plane...

Front View - Before

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Isometric View - Before

Cross Section Curve Path Curves

Front View - After

Isometric View - After

Mitred corner where path was not tangent Path Curves

3.3.3.8 Geometry, Surface, Plane... ... automatically creates a rectangular, planar surface using the standard plane definition dialog boxes. The base of the plane is used for the first corner of the surface. After choosing the appropriate plane, you will be prompted for the width (along plane X) and height (along plane Y) of the plane. The width and height of the plane are combined with the orientation of the plane to determine the other three corners. While limited to rectangular surfaces, this command offers great flexibility in positioning of planar surfaces.

3.3.3.9 Geometry, Surface, Cylinder...

Centerline vector

Start vector Bottom radius

... makes surfaces which represent the curved lateral faces of a cylinder, cone or tube and optionally the planar endcaps. The first input required is the orientation of the object that you will create. You will use the standard vector definition dialog box to define the location and orientation of the centerline of the object. The magnitude of the vector that you specify is also used as the object length. By choosing the various vector definition methods, you can either explicitly specify the length, or automatically determine it from the end points of the vector.

After you have defined the centerline vector, the standard vector dialog box will appear again. This time you must specify a vector which points toward the circumferential location where you want the lateral curved surfaces to begin. Just as the centerline positioned and oriented the surfaces in space, this vector orients the surfaces by rotating them around the centerline. This is fairly obvious when you are going to generate a partial cylinder (< 360 degrees), but is also necessary for full cylinders. If you really don’t care where the surfaces start, you can choose any nonzero vector that is not parallel to the centerline. Finally, the following dialog box is used to specify the remaining parameters:

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Geometry

The shape controls the type of object that will be created. Cones and cylinders only have one lateral (curved) surface, but tubes have two, an inner and outer surface. The various radii must be specified to define the object size. Unnecessary radii for each shape will be grayed and disabled. The inner radii are only available for tubes. They must always be greater than zero, but less than the respective outer radius. The bottom radii are applied at the base of the centerline vector. The top radii are used at the tip of the centerline vector. The default angle (360 degrees) creates a full cylinder/cone/tube. If you only want to create a partial object, specify a smaller angle. The resulting surface(s) will subtend the selected number of degrees of arc around the centerline. End Cap

Cylinder

Tube with capping surfaces

Lateral Cap

Partial Cylinder with capping surfaces

Partial Cone

By default, the Make cap surfaces box is not checked. In this case, only the lateral or curved surface is created. If you check the box, however, this command will also automatically make planar capping surfaces at the top and bottom of the cylinder/cone/tube. Planar lateral surfaces will also be made. When you do not specify an angle of 360 degrees, these surfaces are required to close the sides of the object. With a 360 degree angle, these surfaces are actually inside the object, but will be needed if you later want to use the Geometry, Volume, Surfaces command. They are also useful if you want to make elements in a cross section that you can revolve into a mesh. Note: If you are creating a Parasolid surface, you can only choose from a cylinder or a cone. Make cap surfaces will not be available.

3.3.3.10 Geometry, Surface, Sphere... ... creates a spherical surfaces. You will always be creating a full sphere. This command will create more than one surface to complete the sphere. Pole Vector

-90 degrees longitude

0 degrees longitude 0 degrees latitude

Start Vector

Longitude angles Latitude angles

The first dialog box that you see will be the standard vector definition dialog box. Here you must define the vector which goes from the center of the sphere to the upper (“north”) pole of the sphere. The base is used as the center of the sphere, and the vector components orient the sphere in space. The magnitude of the vector is also used as the default radius, however you will have an opportunity to change this radius later.

Next, another vector is required, which is used to position the origin of the spherical surfaces. Just as the first vector oriented the sphere in space, this vector controls the rotation of the surfaces around the polar vector. If you do not care how the surfaces are rotated, just choose any nonzero vector that is not parallel to the polar vector. Finally, you will see this dialog box:

Geometry, Surface, Offset...

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3.3.3.11 Geometry, Surface, Offset... ....create a new surface by offsetting an existing surface. This command requires you to select the surfaces to offset, and enter a distance to offset. The normals of the surface are used as the offset direction. The offset surface may expand or contract depending on the curvature of the surface and the offset direction.

3.3.3.12 Geometry, Surface, Convert... This command converts a surface generated with the standard FEMAP geometry engine to a Parasolid surface. Generally, you will use Convert to update FEMAP legacy geometry so that you can use it with a newer version of FEMAP.

3.3.3.13 Geometry, Surface, Remove Hole... This command removes interior holes from surfaces by selecting a curve or curves related to that hole. This command works for Surfaces (Sheet Solids) as well as Solids. Remove Hole is looking for “loops” to remove from the geometry. You select which “loops” to remove by selecting the a single curve of an interior hole. FEMAP then tries to “walk” around a loop (starting with the selected curve) and if the “loop” or “chain” of curves are continuous, the hole will be removed from the surface. If this command is used on a component surface of a solid, not only will the hole be removed from that surface, but the “feature” associated with that “loop” and any associated geometry “more interior” than the “loop” will be removed. Very similar to the way Mesh, Mesh Control, Feature Suppression operates. (For more on how that command works, see Section 5.1.2.16, "Mesh, Mesh Control, Feature Suppression...") Hint:

You can use the On Surface selection method (Entity Selection dialog box for curves) to remove all of the “internal holes” from a surface. FEMAP will ignore the curves making up the outline of the surface and send a message to the Messages pane. A similar technique can be used on for solids by using the On Solid selection method

Examples Choose one curve on each “interior hole” and all of the curves making up the “loop” will be found and removed from the surface All internal holes have been removed from the surface

Surface with several “interior holes”

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Geometry

Original Solid Part with “stepped hole”

Curve chosen for “loop” in Remove Face

Resulting Solid Geometry

Original Solid Part with “stepped hole”

Curve chosen for “loop” in Remove Face

Resulting Solid Geometry

Note: Any “Nonmergeable Curves” will be ignored in the command. If you would like to designate curves as “nonmergeable”, use the Modify, Update Other, Nonmergeable Curve command.

3.3.3.14 Geometry, Surface, NonManifold Add... ...is the only command in FEMAP which allows you to create “Non-Manifold Solid Geometry”, an option in the Parasolid modeling kernel which creates “General Bodies” as opposed to regular solids (FEMAP solids) and sheet solids (FEMAP surfaces). The command allows you to Boolean Add sheet solids to one another, as well as add “sheet solids” to Parasolid “solids”. The use of Non-Manifold Geometry can be very useful in creation of mid-surface models with “T-Junctions”, models where shell elements (2-D) and solid elements (3-D) need to be connected and portions of the shell mesh are embedded into the solid mesh, and “solids” with internal “surfaces” used in certain types of analysis. Note:

When bodies have been added together using “NonManifold Add”, many of the other commands on the Geometry, Solid... menu will not function as they did before the geometry was changed from regular geometry to “general body” geometry. A good idea is to have both the surfaces and solids “ready to go” before using the “NonManifold Add” command. If you need to stitch or add more bodies into those that have been put together with this command, you will want to use the Geometry, Surface, Recover Manifold Geometry command (see Section 3.3.3.15, "Geometry, Surface, Recover Manifold Geometry...") to recover component solids and sheet solids, which will allow you to use the commands on the Geometry, Solid... menu.

3.3.3.15 Geometry, Surface, Recover Manifold Geometry... ...essentially the opposite of the Geometry, Solid, NonManifold Add command. The command will take all selected “general bodies” in your model and separate them into component “Manifold” parasolid solids (FEMAP solids) and sheet solids (FEMAP Surfaces). Once the “Manifold” solids and sheet solids have been recovered, the commands on the Geometry, Solid... menu will be available to modify and operate on the geometry again. Note:

To break a “general body” into individual sheet solids for each and every surface, use the Geometry, Solid, Explode command.

Midsurface

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3.3.4 Midsurface The midsurfacing commands are available when using the Parasolid geometry engine. They are useful for generating surfaces from thin-walled solid geometry. The midsurfaces can then be used as the basis of plate meshes. Care must be taken to make certain that the resulting plate mesh adequately represents the model.

3.3.4.1 Single in Solid... ...creates a single midsurface between two surfaces of a solid. The surface is trimmed by the solid so that it is completely contained within the solid. This command requires you to select the two surfaces. Not all surface pairs can be midsurfaced. The command will simply return if the midsurface operation fails.

3.3.4.2 Single... ...creates a single sheet surface between two surfaces. The resulting surface will be larger than both of the selected surfaces. Not all surface pairs can be midsurfaced. The command will simply return if the midsurface operation fails.

3.3.4.3 Trim to Solid... ...trims a surface with a solid. It deletes any parts of the surface which lie outside the volume of the solid. This command requires you to first select the surface to trim, and then the solid to use for trimming.

3.3.4.4 Trim with Curve... ....trims/breaks a surface using a curve. First pick the surface to be trimmed/broken and then pick the curve(s) to trim with. The curves are extended in both directions past the ends of the surface if necessary. Pick this curve

= two surfaces

3.3.4.5 Extend... ....extends a surface by using one of a surface’s edge curves and “extending” the surface using a specified “Extend Shape” method (Linear, Continuous Curvature, or Reflective) to a “target” Solid (or Sheet Solid), location in space, or simply by a distance. Note: If Parasolid cannot extend a surface properly, FEMAP will return an error and let you know that surface cannot be extended using the current parameters. You may want to try a different “Extend Shape” method or “Extend To” option. Whether or not the curves will be imprinted onto the “target” solid or sheet solid is determined by the Geometry, Curve - From Surface, Update Surfaces flag setting. If the flag is on, they will be imprinted (“burned”) into the target surface.

3.3.4.6 Automatic... ...runs the three steps of semi-automatic midsurfacing (Generate, Intersect, and Cleanup below) at once. The command requires you to select the surfaces and specify a Target Thickness (midsurface tolerance). You may want to click the Distance icon button to use FEMAP’s measuring tool to specify an effective target thickness. Any surfaces with a distance between them of less than the target thickness will have a midsurface generated. The command then intersects all created midsurfaces with one another and lastly, deletes all small free floating surfaces.

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Geometry

3.3.4.7 Offset Tangent Surfaces... ...is for use on solids of constant thickness only. You will be prompted for a “seed surface”, then a “tangency tolerance”. All of the surfaces tangent to the “seed surface” within the “tangency tolerance” will be chosen and highlighted. Next a “Mid-Surface Tangent Offset” value needs to be entered. This value is the distance used to offset the selected surfaces towards the middle of the solid part. FEMAP will attempt to calculate this value automatically and will fill the value in if successful. The offset surfaces will be automatically stitched together and finally you will be asked if you want to delete the original solid. Original geometry

Tangent Surfaces Selected

Surface selected as “Seed Surface”

Resulting midsurface geometry (original Geometry deleted)

3.3.4.8 Generate... ...automatically creates all possible midsurfaces from selected surfaces. This command requires you to select the surfaces for generation and enter a midsurface tolerance. Any surfaces with a distance between them of less than the midsurface tolerance will have a midsurface generated.

3.3.4.9 Intersect... ...automatically intersects/splits all selected surfaces with one another. The only input to this command is the surfaces to intersect.

3.3.4.10 Cleanup... ...automatically determines which surfaces can be deleted by checking for small free floating surfaces. You enter the surfaces to check. It does not delete these surfaces, but rather places them on a separate layer so they can be reviewed before they are deleted.

3.3.4.11 Assign Mesh Attributes... ...automatically creates and assigns properties to selected midsurfaces based on the thickness of the solid from which they were created. The original “top” and “bottom” surfaces must be separated by a constant thickness. This command will not create properties which vary in thickness along a surface. You will be prompted with a question asking “OK to Consolidate Properties by Thickness?”. If you answer No, each selected surface will have an individual property created representing the thickness of that portion of the model and assigned to that surface only. If you answer Yes, you will also be prompted for a “thickness percentage tolerance” and any surfaces which have the same thickness, within the specified tolerance, will have a single property created for all of them, then assigned. Along with the property information, the mesh options on each surface will set to use the Quad surface mesher. Note: The “thickness percentage tolerance” is set to a very small number (.1% or .001) in order for the most accurate model to be created. This tolerance can be raised to create less properties, but this may not produce the most accurate finite element model.

Creating Solids/Volumes

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3.4 Creating Solids/Volumes The last commands for geometry creation in the Geometry menu involve creation of 3-D solids and volumes. In FEMAP, there is a distinct difference between volumes and solids. Solids are formed by using the Parasolid modeling engine to form complex 3-D shapes. Boolean operations can be performed with these solids, and they can have voids, or holes in them. The number of faces (or surfaces) to a solid is not limited. Solids provide an excellent method to form complex 3-D shapes, and can be automatically meshed with tetrahedrals, or if care is taken, semi-automatically meshed with hexahedrals. Volumes are formed from analytics as well as joining selected surfaces. Volumes generated from surfaces require 46 surfaces which form a complete enclosed volume. Voids (or holes) are not permitted in volumes. The restrictions on number of surfaces and no voids limits the usefulness of volumes. They are typically only created when you must model a very regular pattern volume (with no holes), and brick or wedge meshes are essential.

3.4.1 Volumes The Geometry, Volume menu allows you to create volumes which can be used for meshing of solid elements. All volumes in FEMAP are essentially the same, although you can create volumes with several different “shapes”. In this case, “shapes” refers to the number of surfaces that are used to bound the volume. The following table summarizes those shapes. Shape

Characteristics

Brick

Six quadrilateral surfaces

Wedge Five surfaces, top and bottom are triangular, others are quadrilateral

Pyramid Five surfaces, bottom is rectangular, others are triangular

Tetra

Four triangular surfaces

You can choose any of these volume shapes that you need to fill the portion of your model that you want. In fact, the shapes shown are just the basic outlines if you used regular, planar surfaces. In fact, any surfaces can be used and the shapes really refer more to the overall topology than the actual shape of the volume. Volume Parameters When you are creating volumes, you will see numerous dialog boxes with a Parameter button. Choosing this button lets you set the ID and color of the volume. The ID is not usually of great concern. You can choose a color for

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Geometry

the volume either by typing its number or by pressing the Palette button and choosing from the standard palette. If you do not set a color, you can always change the color later with the Modify, Color, Volume command. Displaying Volumes The display of volumes is largely based on displaying the surfaces that are used to define the volume. The only thing actually drawn for the volume is an outline around the surface boundaries. You can control the overall display by adjusting the surface divisions and surface display options. Geometry, Volume Menu The Geometry, Volume menu is partitioned into three sections based upon the method of creation. The first section of commands (Corners, Surfaces, Between), create volumes from framework geometry of points, surfaces, or both. The second section (Extrude, Revolve) perform operations on a surface to create a volume. The final section (Cylinder, Sphere) involve analytical volumes. Each command on the Volume menu is discussed further below

3.4.1.1 Geometry, Volume, Corners... ... creates volumes simply by specifying the coordinates of the corners. You do not need any existing geometry to use this command - it creates all of the required points, lines and surfaces. All of the input for this command uses the standard coordinate definition dialog boxes. Each corner is defined using a separate dialog box. To create volumes having different shapes, simply choose Cancel when all of the required corners have been defined. You will be asked whether you want to cancel, backup, or create a volume with that number of corners. If you press Cancel at a point when a volume cannot be created, you will be given a chance to backup or abort. This is an ideal way to update incorrectly specified coordinates before you finish the command. The following table shows the number of corners that are allowable when creating volumes: Shape

Corners

Brick Wedge Pyramid Tetra Brick

8

8 6 5 4

3

3

1

2

Pyramid

Tetra 3

1

2

1

5

3

4

The convention for defining corner locations is shown in the figure.

5

4

6 4

Never Corner 7 Corner 6 Corner 5 Wedge 6

7

5

Press Cancel when Defining

2

3.4.1.2 Geometry, Volume, Surfaces...

1

4

2

It is always best to follow the conventions shown for specifying the order of the corner locations; however, FEMAP does check the locations that you specify to see if they match the correct shape. If they do not, FEMAP will automatically change the selection order and attempt to create a valid volume. This “fixup” will often create the correct volume even if you specify the corners in a different order, but there is no guarantee. The same volume will be created no matter what coordinate system or systems you use to define the corner locations. Straight lines will be used to connect all of the corners, and all surfaces will be bilinear. Alt+F9

... allows you to select and combine existing surfaces to form a volume. The only dialog box required is the following one:

Geometry, Volume, Between...

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Here you select the shape of the volume that you want to create (brick, wedge, pyramid or tetra) and the surfaces that will define the volume. You can select any type of surface, but you must follow these guidelines: •

The surfaces that you choose must have the appropriate shape (triangular or quadrilateral) to define the shape of volume that you choose. The required shapes are listed in the table at the beginning of this section for the Geometry, Volume menu.



All surfaces must have coincident edges. The surfaces do not have to use the same edge curves, but they must use exactly coincident curves, so that there are no gaps between the edges. If the surfaces do not use the same edges, the curves will be automatically merged by this command. This insures that the surfaces that you choose form a complete closed volume.

You do not have to choose surfaces that have their parametric directions aligned, nor do you have to choose the “sides” in any particular order. The volume parametric directions are based on the parametric directions of the first surface that you select. The first and second (s and t) volume directions are aligned with the parametric directions of the bottom surface. The third parametric volume direction (u) goes from the bottom to the top surface. If these directions do not form a right-handed coordinate system, then the s and t directions are reversed (negated, but still along the same direction).

Top

Side

Side

t direction u direction s direction

Bottom

Note: You can choose any type of surface for a volume, but you will probably not want to choose any Bezier surface that was created by the Geometry, Surface, Aligned Curves command. Since this type of surface does not typically follow its edge curves exactly, any volume that you create may have gaps along its edges and you will not be able to use it for meshing.

3.4.1.3 Geometry, Volume, Between... 2 Surfaces

To Surface

From Surface

Surface and Point

To Point

From Surface

... creates a volume between two surfaces, or between a surface and a point. When you choose the 2 Surfaces option, both surfaces must have the same shape - either triangular or quadrilateral. Quad surfaces form a brick volume, while tri surfaces create a wedge. The Surface and Point option is used to create the other volume shapes. With this option, choose a quadrilateral surface to create a pyramid, or a triangular surface to form a tetra. .If you are using the 2 Surfaces option, you simply choose the two surfaces which form the top and bottom of the brick or wedge. All of the side surfaces are automatically created between the respective edges of these surfaces. The same approach is followed for the Surface and Point option, but instead of specifying a top surface (To Surface), you will specify a top point. The point must already exist, you cannot specify coordinates. Again the required side surfaces and curves are automatically created.

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3.4.1.4 Geometry, Volume, Extrude... Extrusion Vector

Selected Surfaces

... creates volumes by moving or extruding one or more surfaces along a vector. You simply select the surfaces to extrude using the standard entity selection dialog boxes, and the vector to extrude along, using the vector definition dialog boxes. One volume will be created for each surface that you select. The vector that you choose can be located anywhere, but the direction and magnitude are used to define the direction and length of the extruded volumes.

All quadrilateral surfaces will extrude into brick volumes. Triangular surfaces extrude into wedge volumes. Other volume shapes cannot be created with this command.

3.4.1.5 Geometry, Volume, Revolve... ... is similar to the Geometry, Volume, Extrude command described above. In this case the volumes are created by revolving the original surfaces around a vector (the axis of revolution), instead of extruding them along the vector. In addition to selecting the surfaces to revolve with the standard entity selection dialog box, and specifying the axis of revolution with the vector definition dialog boxes, you must also define the angle of revolution. This is the angle through which the surfaces will be rotated around the axis of revolution vector to form the volumes. As the surfaces are revolved, all of the additional curves and surfaces which define the volume will be created automatically. When you are specifying the axis of revolution vector, the location and direction are important, the magnitude is not. The location and direction are needed to define the rotation.

Axis of Revolution

Angle of Revolution Selected Surfaces

You should never specify an axis of revolution that crosses any of the surfaces that you are revolving. If you do, the resulting surfaces and volumes will be twisted, and will be useless for meshing. In addition, there are several special cases that can arise when you revolve surfaces that have one or more points or edge curves that lie on the axis of revolution. For example, if you revolve a triangular surface that has one point on the axis, you will create a pyramid-shaped volume. If you revolve a triangular surface with one edge on the axis, you will create a tetra. There are similar cases with quadrilateral faces.

3.4.1.6 Geometry, Volume, Cylinder... ... is identical to the Geometry, Surface, Cylinder command except that it creates the volume, in addition to the surfaces. Since you will be creating a volume, capping surfaces will always be created. Otherwise, the volume would not be closed. For more information, see Section 3.3.3.9, "Geometry, Surface, Cylinder...".

3.4.1.7 Geometry, Volume, Sphere... ... is identical to the Geometry, Surface, Sphere command except that it creates the volume, in addition to the surfaces. Since you will be creating a volume, capping surfaces will always be created. Otherwise, the volume would not be closed. For more information, see Section 3.3.3.10, "Geometry, Surface, Sphere...".

Solids

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3.4.2 Solids These commands provide tools for building solid models in FEMAP. They are available when the Parasolid geometry engine is active. The Solid menu is partitioned into six major segments: •

Activate - select and or name the active solid



creating/editing- Add/Remove Material, Extrude, Revolve, Primitives, Stitch, Explode



modifying - Fillet, Chamfer, Shell



Boolean operations - Add, Remove, Common, Embed, Intersect



slicing/face operations - Slice, Slice Match, Slice Along Face, Embed Face



Cleanup - cleanup the active solid

The functionality of these commands are explained in more detail below.

3.4.2.1 Geometry, Solid, Activate... ... is used to change between active solids, change the title of the highlighted solid, or to make no solid active. When you select this command, the Solid Manager dialog box appears.

Title Filter

Clear Title Filter

Update Title Allows you to rename the highlighted solid.

None Active Choose this option to deactivate all solids. Note:

Unlike other similar Manager commands, such as Model, Load, Create/Manage Set and Model, Constraint, Create/Manage Set, you cannot create a new solid by inputting an unused ID. You must create a new solid by using one of the commands under the Solid menu which actually forms the solid and select New Solid. FEMAP will then automatically create a new solid with the title you input.

3.4.2.2 Geometry, Solid, Add/Remove Material... ... does not perform any functions; however, it does set the defaults for the commands below. If this option does not have a check mark next to it, the default will be Add. If there is a check mark, the default will be Remove.

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Geometry

This is a convenient method to toggle between defaults if you are performing many additions, then removals. However, you can still toggle between Remove and Add once you get into the command itself. Therefore, you are not required to change this option.

3.4.2.3 Geometry, Solid, Extrude... ... allows you to move a boundary or surface through a vector, and either create a new solid from the extrusion, remove material or add material. When you invoke this command, you will see the following dialog box:

The dialog box is separated into four major sections: Material, Direction, Length, and option buttons. Note: You cannot extrude a FEMAP base (standard) surface, or a nonplanar boundary surface.

Material This section controls the type of action to perform. The default will be based upon the Add/Extrude Material option (see Section 3.4.2.2, "Geometry, Solid, Add/Remove Material..."), or the last previous operation. You can create a new solid, add to the current solid (Protrusion), or remove from the current solid (hole). The Add and Remove commands are similar to the Geometry, Solid, Add and Remove commands, except you do not have to form an additional solid to add or remove. You simply move a boundary or surface along a vector to add or remove material.

Direction This option controls whether you extrude in the negative, positive, or both directions. You will see a small white arrow along the surface or boundary denoting the current direction. If you switch from positive to negative, the direction of the arrow will switch. FEMAP can extrude both planar and non-planar surfaces, but it can only extrude planar boundaries. For all planar entities, FEMAP will automatically choose the normal to the entity as the vector along which to extrude. If you want to extrude a non-planar surface, or want to extrude along a vector other than the normal, you must select the extrusion vector by pushing the Along Vector... button.

Length You can extrude to a particular depth along the vector, to a specific location, or through all of the solid(s) along the vector direction. If you select the location option, you must input the location using the standard coordinate definition dialog box after pressing OK on the Extrusion Options dialog box.

Options Buttons These buttons allow you to change the defaults for the extrusion. Active Solid... ...allows you to change the active solid which will be used in the extrude operation. When you select this option, a list of the available solids will be provided (the same dialog box that is used in the Geometry, Solid, Activate command). Simply select the appropriate solid. Along Vector... ... uses the standard vector definition dialog box to define the vector along which to extrude. If you do not select this option, FEMAP will automatically extrude along the normal vector for all planar surfaces. If you attempt to extrude a nonplanar surface, you must use this option to define the extrusion vector. You cannot use this option to extrude boundary surfaces. Boundary surfaces area always extruded normal to their definition plane.

Geometry, Solid, Revolve...

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Pattern... ... allows you to create multiple extrusions from a single surface or boundary extrusion. This is an extremely useful option when multiple holes, in a symmetrical pattern are required through a solid. You can simply define one boundary/surface, and then choose Pattern. When you choose this command, the Patterns dialog box will appear. None The default option is None. A single extrusion will be performed with this option. Rectangular This option allows you to identify the number and spacing in Y. If you are planning to use this option, the workplane must be aligned with the pattern. Also, the original surface/boundary you create should be at the most negative position on the workplane. FEMAP will automatically move in the positive X and Y workplane directions (unless you specify a negative distance) to create additional entities in the pattern. The spacing values input must be the distance form center to center of the boundary/ surface you are extruding. Radial This option is very similar to Rectangular, except it defines a radial pattern. You input the center, the number, and the total angle, and FEMAP will create these extrusions into or through the solid. Examples Below you will find two examples of a pattern definition. Rectangular Pattern The first example uses a rectangular pattern of 3 in X and 3 in Y with the same spacing for both. The origin is specified as the center of the circle in the workplane in the bottom left corner. FEMAP then uses the X spacing and Y spacing to form the 9 holes in the solid. Radial Pattern The Radial Pattern is similar, except a number of 6 and a total angle of 360 degrees was specified.

Rectangular Pattern

Radial Pattern

Surface This option lets you to select the surface to extrude.

3.4.2.4 Geometry, Solid, Revolve... ... is very similar to Geometry, Solid, Extrude except it revolves around an axis of revolution instead of extruding along a vector. When you select this command, you must input the axis of revolution using the standard vector definition dialog box. The Revolve Options dialog box then appears. This dialog box is almost identical to the Extrude Options dialog box above (Geometry, Solid, Extrude), except for a few modifications (see Section 3.4.2.3, "Geometry, Solid, Extrude...") The Material (New Solid, Add, or Remove) and Directions (Positive, Negative, or Both) sections are identical, and the Length section has options for Angle, To Location, and Full 360 degrees instead of Depth, To Location, and Full 360. The only other difference is you can choose to change your axis of revolution (instead of the Extrusion Vector) by selecting the axis of revolution option.

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3.4.2.5 Geometry, Solid, Primitives... ... can be used for such geometry primitives as cylinders, blocks, and cones. This command can be used to form a new solid or to add/remove material from an existing solid. When you select this command, the Solid Primitives dialog box appears. This dialog box is very similar to the Extrude Options and Revolve Options dialog boxes. Each of these areas are discussed below.

Material You can create a new solid, add to, or remove from an existing solid just as in the Extrude/Revolve commands above. For this particular command, however, you also have the option to form a new solid from common areas of the primitive you are about to create and the current active solid.

Direction You may also choose to move in a positive or a negative direction, just like the commands above.

Origin You simply specify a location for the origin of the primitive. If you plan on using a rectangular pattern, you should use the origin of the primitive which is in the most negative position in the workplane, since FEMAP will always move in the positive direction to create the pattern.

Primitive This section defines the actual primitive to be created. You can create a block, cylinder, cone, or sphere. For the block, you can input the origin at the center or corner of the block. You must then specify the distances in the X, Y and Z directions. These directions are all relative to the workplane. For a cylinder you simply input a height and radius. A cone requires a top and bottom radius as well as a height. There are two options for sphere, “Sphere” requires only a radius for input and creates a sphere with 8 three-sided surfaces, while “Sphere - Alt” requires only a radius and creates a sphere from 6 four-sided surfaces.

Sphere

Sphere - Alt

Options You may also change the active solid (Active Solid) or choose to create a Pattern (see Section 3.4.2.3, "Geometry, Solid, Extrude...").

3.4.2.6 Geometry, Solid, Stitch... ... creates a solid from a series of surfaces. The only inputs required for this command are the surfaces themselves, a stitching tolerance, and whether “mergeable curves” should be cleaned up. The tolerance can be adjusted to facilitate the closing of gaps between surface edges. This is a very useful command when reading trimmed surfaces from an IGES file. You can read an IGES file, and then use this command to generate a Parasolid solid from the IGES surfaces. You can then manipulate this solid just like any other solid you would have created in FEMAP.

Geometry, Solid, Explode...

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When Cleanup Mergeable Curves is “on”, which is the default, FEMAP will remove all internal curves which are redundant. The “stitched” geometry will contain as few surfaces as possible by removing curves which are not needed to define the overall topology of the geometry. When “off”, all of the surfaces being stitched together will remain in the geometry. Original Geometry

Stitched Geometry Cleanup Mergeable Curves “On”

Stitched Geometry Cleanup Mergeable Curves “Off”

3.4.2.7 Geometry, Solid, Explode... ...creates independent surfaces from a solid. The underlying solid no longer exists. The only input for this command is a solid. This command is quite useful because it allows you to modify surfaces on solids, then, if desired, stitch them back into a solid.

3.4.2.8 Geometry, Solid, Fillet... ... allows you to create fillets on a solid model. When using this command, you must be careful to select the appropriate curve for filleting. This command works slightly different than the Modify, Fillet command in that you are modifying a solid, not individual curves. Therefore, you must select an edge of the solid, and that edge will become “rounded” based upon the radius you input. The input for this command is simply the curve(s)/edge(s) to fillet, and the radius of the fillet. Below are a few examples of filleting a solid.

Examples

Fillet Top Curve

Fillet Top + Side Curves

3.4.2.9 Geometry, Solid, Chamfer... ... operates identically to Geometry, Solid, Fillet except it produces a chamfer instead of a fillet. Input for this command is simply the solid edge (curve) and the chamfer length. Examples of this command are shown below.

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Geometry

Examples

Chamfer Top Curve

Chamfer Top + Side

3.4.2.10 Geometry, Solid, Shell... ... allows you to “hollow out” a solid. Simply select the surfaces to pierce (the surfaces on the solid to be hollowed out), and the thickness of the solid shell. FEMAP will automatically remove the interior portion of the surface and leave an outer thickness equal to the input of the thickness and then move through the solid, normal to the surface, and remove material until it reaches within a thickness value of the opposing surface. To shell a solid completely and remove all material in the interior, simply choose two opposing surfaces.

Examples

Pierce One Surface

Pierce Two Surfaces

3.4.2.11 Geometry, Solid, Thicken... ... allows you to “thicken” or “thin out” (depending on the selected options) an existing solid using a component surface or surfaces or “thicken” a surface (sheet solid) into a solid by extruding in one specified normal direction or both. Offset The In and Out “Offset” directions are determined by the normal direction of the surface, with the “Out” direction being in the normal direction. For solids, the Out direction will always face away from enclosed volume.

Geometry, Solid, Thicken...

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When using “thicken” on a surface (sheet solid) not associated with any solid, you simply choose the surface(s) to “thicken”, choose an offset direction (In and/or Out), and enter a value. Surfaces showing Normals

Solids created using “Out” and a value of “3 units”

Two Surfaces with opposite Normals

Note: You can turn on the “Surface normals” using the View, Options command. Once in the View Options dialog box, choose the Tools and View Style category, then choose “Curve and Surface Accuracy” from the Options list. Change the option in Parametric Directions to either “1..Show All Arrows” of “3..Show Surface Arrows”. Note: You can reverse the normal direction of a surface (sheet solid) using the Modify, Update Other, Surface Normal command. Options These options are used to control the way the “thicken” command behaves. Some are only available in certain situations.

Auto Cleanup - Runs a portion of the Solid, Cleanup command to make sure any new solids that have been created are valid solids and also tries to remove any “extraneous” material (slivers, hanging edges) from the “thicken” process. This option is on by default and is a recommended every time this command is used. Thick Individually - Creates an individual solid for each surface that was selected to “thicken”. Doing this allows you to pick and choose which newly created solids to “boolean” (add, embed, etc.) or use in other operations. Delete Original Surfaces - Simply deletes the Original Surface that was used to “thicken”. Is on by default, but may be turned off if you would like to use the surface for additional geometry operations (extrude, revolve, etc.) Auto Boolean When using “thicken” to alter a solid by choosing surfaces associated with the solid, you will have some additional options. These options allow you to combine the “thicken” operation with FEMAP Boolean operations. Essentially, the geometry will be “thickened” and then the selected Boolean operation will occur. Only “thickened” surfaces from a particular solid can be booleaned with that solid (i.e., you can NOT take a surface from a solid, “thicken” it, and then boolean it into a different solid).

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Geometry

None - The new geometry will be created with no effect to existing geometry in the model, even if the “new” solid created with “thicken” overlaps the original surface’s associated solid. Add - The new geometry will be “added” to the solid after the “thicken” operation. This option is good to use when you want to “thicken” a portion of your model. Hint:

You can reduce the diameter of a hole by choosing all the surfaces of the hole, selecting the Out offset direction, and the Add Auto Boolean Option.

Subtract - The new geometry will be “subtracted” from the solid after the “thicken” operation. This option is good to use when you want to “thin out” a portion of your model as natatorial will be removed. Hint:

You can increase the diameter of a hole by choosing all the surfaces of the hole, selecting the In offset direction, and the Subtract Auto Boolean Option.

Embed - The new geometry will be “embedded” into the solid after the “thicken” operation. This Boolean is a good option to select when you need “multiple elements through the thickness” and can be used in conjunction with “adjacent surface matching” to create a continuous mesh of this type. Hint:

You can create a cylindrical region for meshing around a hole by choosing all the surfaces of the hole, selecting the In offset direction, and the Embed Auto Boolean Option.

See the examples below for how the “thicken” command can be used with Boolean operations. Examples: Choose a single surface and use the “Out” Offset and Add Boolean to “thicken” a portion of your solid Reduce Radius using a combination of “Out” Offset and Add Boolean

Increase Radius using a combination of “In” Offset and Subtract Boolean

Create Mesh Region using combination of “In” Offset and Embed Boolean

Choose a single surface and use the “In” Offset and Subtract Boolean to “thin out” a portion of your solid

Choose all of the “outside” surfaces, the “In” Offset, and the Embed Boolean to partition the solid for “two elements through the thickness” mesh

3.4.2.12 Geometry, Solid, Remove Face... ... allows you to “Remove a face” from a solid. Simply select the surfaces to remove (surfaces that create fillets, chamfers, holes, bosses, tabs, cut-outs, etc.), and the faces will be removed from the solid. FEMAP will automatically “fill-in” or “remove” the portion of the solid that was represented by the chosen face. For example, a hole can

Geometry, Solid, Add...

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be removed (material will be added to fill-in the hole) by choosing to “remove” the interior faces that make up the “sides” of the hole or a boss can be removed (material is taken away) by choosing to remove a surface that makes the “side” of a boss.

Examples Remove the two inner faces of a hole

The hole has been removed and the block is solid again

Remove the faces that are fillets

The fillets has been removed from the geometry

3.4.2.13 Geometry, Solid, Add... ... forms one solid from multiple, connected solids. The only input required for these commands are the solids which are selected through the standard entity selection dialog box. FEMAP intersects all selected solids to form one solid composed of the volumes of all selected solids. Note: If a solid is not connected to any of the other chosen solids, it will not be added and will remain as a separate entity.

Example

+

=

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Geometry

3.4.2.14 Geometry, Solid, Remove... ... modifies one solid by subtracting other solids from it. First select the base solid (the one to be modified), and then select the solids to subtract. FEMAP removes material common to the solids from the first solid (the base solid). The subtracted solids are removed from the model.

Example

=

3.4.2.15 Geometry, Solid, Common... ... is very similar to Geometry, Solid, Add except it creates a solid from the shared volumes between two solids instead of the total volumes of both.

Example

Common

= 3.4.2.16 Geometry, Solid, Embed... ...similar to the common command except that it forms multiple solids: one from the shared volumes of each “embedded” solid and one from the remaining volume of the base solid. You are first asked to pick the base solid, then any number of solids to embed.

Example

Embed

Pick this solid first

=

Geometry, Solid, Intersect...

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3.4.2.17 Geometry, Solid, Intersect... ...automatically breaks surfaces on selected solids at their intersections. The figure shows the surfaces of two solids before and after intersection. Surfaces Before Intersect

Surfaces After Intersect

3.4.2.18 Geometry, Solid, Slice... ... forms two solids by using a cutting plane to slice through a solid. This command simply requires you to select the solid, and define the cutting plane using the standard plane definition dialog box. FEMAP will then slice the solid and form two individual solids from the first solid. Hint:

This command is extremely useful when importing CAD files of symmetrical parts. Most solid models in CAD systems will be of the entire model to generate drawings. You can use this command to slice the part through its plane(s) of symmetry and produce a much smaller and efficient model for meshing and analyzing. If you need to mesh the entire model due to non-symmetric loading conditions, simply mesh the sliced portion and then reflect the mesh. You will be able to produce a much better mesh in less time, than if you attempt to mesh the entire part. You will also be guaranteed to obtain a symmetrical mesh

3.4.2.19 Geometry, Solid, Slice Match... ...similar to the solid slice command, but it will leave matching faces on both solids. The faces can then be matched for meshing using the mesh size commands. This command is useful for making multiple solid meshes (tetrahedrons or hexahedrons) that can be sewn together using the coincident nodes command.

= +

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Geometry

3.4.2.20 Geometry, Solid, Slice Along Face... ...similar to the slice match command but a face of the solid is selected instead of a plane. The face can be planar or curved.

= + Pick this face

3.4.2.21 Geometry, Solid, Embed Face... ...extrudes a face into a new solid and embeds it into the solid that contained the face. You must first select a face, then you will have several optional methods that you can use to embed the face. Usually you will simply want to use the defaults, by pressing OK.

Embedding Direction and Distance The direction that the face will be embedded can be determined or specified in a number of ways. If you are embedding a planar face, the direction can be automatically determined from the plane normal. If you choose Automatic, the surface normal will be used as the embedding direction, and the face will be embedded through your entire solid. If you choose Specify Direction, you will be asked for a vector to use for both the direction and the distance to embed. If you choose Specify Offset, you will simply be asked for an offset distance. The surface will be offset through that distance and embedded. If you use this method with non-planar surfaces, the resulting embedded solid will not be a simple extrusion. The sides of the solid are projected normal to the original surface.

Curves In most cases, you will want to embed the entire face. That means choosing the Outline Only mode, where only the outline of the face is used - holes are ignored. If you choose All Curves, curves on holes will also be used, so any geometry that is “inside” the holes will be sliced out of the embedded solid. If a planar face is selected FEMAP uses the face normals as the extrusion direction. If you select a curved surface, FEMAP will ask you for a direction vector to use for the extrusion.

Geometry, Solid, Cleanup...

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two solids

= pick circular face

3.4.2.22 Geometry, Solid, Cleanup... ... is used to “cleanup” a solid. This command will check the solid, and remove any extraneous features which are not part of the actual solid, but may have developed during export from a CAD package or from Boolean operations on it. If a portion of your solid appears inaccurate, or drawn incorrectly, use this command to see if you can remove it. Remove Redundant Geometry Redundant geometry is geometry that is not required to define the volume of the solid. Examples of this could be curves that have been imprinted in a face to split it into regions, points used to split curves, or multiple surfaces that are all really part of the same underlying geometric surface. If you check this option, this geometry will be removed, resulting in a simplified solid. Note: Do not use this option if you have imprinted curves or performed some of the matching commands since imprinted curves are considered extraneous and will be removed. Remove Sliver Surfaces “Slivers” are small faces that are created because of numerical inaccuracies in Boolean or other solid modeling operations. Typically these faces are much smaller than the other faces that define your solid. While they are small, they can cause great difficulties in meshing. They will often completely prevent a part from being hex meshed. This option removes these surfaces and attempts to restitch your solid without them. This option is only available with Parasolid geometry. Check Geometry Once you have cleaned geometry, especially if you removed sliver surfaces, it is often good to check it to be confident that it is still a good, usable solid. You may even want to do this without any of the other options just to check the validity of a solid that you are creating. Match Model Scale Factor If you have a model containing geometry in more than one scale factor, this command will take all selected geometry and adjust the geometry’s internal scale factor to the Solid Geometry Scale Factor that is currently set in File, Preferences under the Geometry preference.

Advanced Cleanup If you press the Advanced Cleanup button, you will see a list of alternate ways that you can attempt to repair your geometry. These options give you more control over repairing specific problems. In most cases in the dialog box, you will see a check box to turn a specific cleanup option on or off, along with an associated tolerance (if appropriate), to specify the characteristic size where you want cleaning to take place. Cleaning Options “Repair Edges” allows you to specify a tolerance which will be used to repair the edges of your solid. If “Smooth or Split Discontinuities” is checked, then surface or curve G1 discontinuities will be removed. If the discontinuity has a change in tangent of less than the tolerance that you specify then the discontinuity will be smoothed. If the change

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in tangent is greater than the tolerance then the face or edge will be split at the surface’s or curve’s discontinuity. If a surface contains self-intersections, which lie outside its face boundaries then this portion of the surface will be removed by splitting the surface, if you check “Remove Surface Self Intersections”. This may result in the surface being split into several surfaces. If you are concerned that surface geometry be preserved at all costs, and repairs should be confined to getting face boundaries repaired as far as possible, then turn off “Allow Surface Modifications” - this will leave surface geometry unchanged. Small Feature Options “Remove Spikes” attempts to heal surface trimming curves that have spikes as shown. “Remove Small Edges” removes very short edges which are below the length that you specify. Similarly, “Remove Small Faces” removes small faces. A small face is defined as any face, no matter what shape, that fits completely within a sphere of the radius that you specify in this option. “Remove Sliver Faces” also removes insignificant faces, however in the case of slivers, they may only be small in one direction and long in the other. These are faces with high aspect ratios, and small area.

spike

Geometry Simplification Options If “Convert to Analytic Geometry” is on, B-Spline curves and surfaces are converted, whenever possible, to simplified analytic geometry. Curves can be simplified to lines, circles or ellipses. A surfaces can be simplified to a plane, cylinder, cone, sphere or torus. The original B-Spline geometry must match the analytical representation within the specified tolerance or it will not be converted. Edge Healing Options These options attempt to heal inaccuracies in the edges of a solid or surface. They repair edge and vertex geometry by recalculating geometry that repaired tangential surfaces does not meet precisely. The tolerance you specify is the tolerance to surfaces which the edges will be recomputed to meet the other constraints imposed by the model - for example, surface tangency. This option will also repair misalignment between the axes of analytical surfaces - for example, two very nearly coplanar surfaces are made planar. Likewise, very small mismatches between the radii of cones, cylinders, spheres and torii are corrected. If “Merge Edges” is on, then after healing the inaccurate edges, any redundant edges in the model will be removed. Surface Heal and Stitch Options These options allow you to stitch surfaces into a solid, or automatically explode and restitch an existing solid. In addition to simply stitching, if you turn on “Heal Surfaces”, then additional cleaning options are performed before stitching - self intersections of curves will be removed, and self-intersections in sharp corners of 3-sided surfaces will be removed. If “Smooth or Split Discontinuities” is checked, G1-discontinuities in curves and surfaces will be removed, and closed geometry is made periodic. If “Replace Missing Geometry” is on, then an attempt will be made to fit surfaces in any remaining holes in the model to close it into a solid.

Copying Geometry

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3.5 Copying Geometry FEMAP provides robust tools to make duplicates of existing geometry. There are five commands which can be used to make duplicates of existing geometry: •

Copy



Radial Copy



Scale



Rotate



Reflect

These operations can be performed with any geometry, including points, curves, surfaces, volumes, and solids. When you copy geometry that is comprised of other geometry (such as surfaces which are comprised of curves), FEMAP will automatically copy these “framework” entities, and then connect them properly to form the new copies. Each of these capabilities is described in more detail below.

3.5.1 Geometry, Copy Commands You can use the copy commands to duplicate existing points, curves, surfaces, volumes, or solids. All Geometry, Copy commands require the exact same input, independent of the geometry you are copying. After selecting the appropriate command for the type of entity you want to select, the standard entity selection dialog box will appear. Simply choose the desired entities, and FEMAP will display the following dialog box. After you set the Generation Options and press OK, you will see the standard vector definition dialog box. This vector defines both the direction and distance from the selected entities to the first copy. If you specify multiple repetitions, each additional copy will be located along the same vector, at the same distance from the previous copy. Optionally, you can specify a new vector for each repetition by selecting the Update Every Repetition option.

Specifying Generation Options The generation options control how many copies FEMAP will make, and choose what is transferred from the “original entities” to the “resulting entities”. You have the following choices: Match Original: Used to choose what is transferred from the “original entities” to the new “copied entities”. Color and Layer - when this option is “on”, the copied entities will have the same Color and Layer as the original entities. Otherwise, the copied entities will use the “Active” Color and Layer in the model for that specific entity type. The “Active” Layer and Color can be controlled using the Tools, Parameters command. This is the same as if you had created new entities using the geometry creation commands (for example, Geometry, Point). Mesh Sizes, Loads, Constraints... - When this option is “on”, the copied entities will have identical mesh sizing, geometry-based loads, and geometry-based constraints applied. FEMAP will automatically create local coordinate systems to define the loads and boundary conditions properly, if necessary. Note: When using “Geometry, Copy, Curves”, the Mesh Sizes, Loads, Constraints option is not available. If the original curves have a mesh size applied, then the copied curves will as well. No curve-based loads or constraints will be applied to the copied curves. Repetitions: By default this option is one. One repetition will create one copy of each selected entity. If you want multiple copies, set this option to the number desired.

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Update Every Repetition: When this option is off, FEMAP will only ask you for one vector that will be used to position the copies. In this mode, FEMAP will always offset the position of the current repetition from the position of the previous repetition, based on the direction and length of the vector that you define.

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If you select the Update Every Repetition option however, FEMAP will ask you for a new vector before every repetition. This new vector will be used to offset from the original entities you selected, not from the previous repetition. You will want to check this option whenever you want to create multiple copies that do not lie along a single vector. Copy in Same Location: Creates a copy of the selected entities without specifying a vector to move them (i.e., creates coincident entities).

Copying in Non Rectangular Coordinates

Make 3 copies along this vector

FEMAP always creates copies along the vector that you specify, that is along a straight line. You can specify the vector in any convenient coordinate system. You cannot however, use it to create a copy in a rotated location by choosing the angular direction in a cylindrical coordinate system. You must use the rotation commands to create rotated copies.

3.5.2 Geometry, Radial Copy Commands The commands on this menu provide an alternative to the Geometry, Copy commands. Instead of copying all entities along a constant vector, as those commands did, the Geometry, Radial Copy commands use a different, radial vector for each entity to be copied. When you choose one of these commands, you will be asked to select the entities to be copied, and to define the generation options. This portion of the process is identical to the normal copy commands. FEMAP will ask a question: Clicking “Yes” allows you to choose a location which defines the center of the radial pattern. Clicking “No” prompts you to choose a vector for constant offset. Finally, you must specify the Radial Copy Length, the radial distance between each original and the associated copy.

When using the “Move Around Point/Spherical” method, FEMAP will compute a direction vector for each entity which runs from the center that you chose, to the entity, as shown here.

Copy Original

In a three dimensional case, these commands are actually a spherical copy, since the copy vector is computed from the “center of the sphere”. For more information regarding the specifics of using the various generation options refer to Section 3.5.1, "Geometry, Copy Commands"

Center

Radial Vectors

Offset

Note: This command is not available for solids. Also, surfaces/curves created using the Parasolid modeling engine can also not be selected. It is used most often to copy arcs and other basic geometry. You must also be careful when using this command with arcs. You should typically use the center of the arc as the center of the radial pattern, otherwise the arc formed by the copy may be significantly different than you would expect.

Geometry, Scale Commands

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3.5.3 Geometry, Scale Commands The Geometry, Scale commands are very similar to the Geometry, Radial Copy commands. They create one or more copies of selected entities, offset from a center location. In this case however, instead of specifying a constant offset from the original, the new copy is formed by scaling the distance from the center to the original. These commands start by selecting the entities to be copied, and defining the generation options. This portion of the process is identical to the normal copy commands. Just as in the Geometry, Radial Copy commands, you next choose a location which defines the center of the pattern. Finally, you must specify the scale factors. Scaling can be done in one or more directions. By specifying the same scale factor in all three directions, a spherical copy can be made. A cylindrical copy can be accomplished by specifying the same factor in two directions, and a unit (1.0) scale factor in the third direction - along the axis of the cylinder. For this type of operation, a coordinate system can also be chosen if the axes of the desired cylinder do not coincide with the global axes. FEMAP will compute a direction vector for each entity which runs from the center that you chose, to the entity, as shown here. In these commands, both the direction and magnitude of these vectors is used. The direction is used to determine the original “copy” vector components. These components are multiplied by the scale factors to calculate the final offsets from the center location of the copy. If you use different scale factors in different component directions, the copy will not lie along the vector from the center to the original.

Copy Scale=2.0 Original Center Scale=2.0

For more information on using various generation options, see Section 3.5.1, "Geometry, Copy Commands". For information on specifying scaling factors, see Section 3.6.2.7, "Modify, Scale Menu". Note: If you use a scale factor of 1.0, the resulting copy will be located at the same location as the original in that coordinate direction. Scale factors of (1.0, 1.0, 1.0) will result in a completely coincident copy of the originals.

3.5.4 Geometry, Rotate Commands Like the Geometry, Copy commands, these commands create duplicate copies of model entities. Instead of copying along a vector, these commands rotate the duplicate copies around a vector. FEMAP displays the standard entity selection dialog box to allow you to select the entities you want to copy. This is followed by the same Generation Options dialog box. All of the options in this box are used just as in the Geometry, Copy command. Following the Generation Options dialog box, you will see the standard vector definition dialog box. This vector is used to specify the axis that you want to rotate around to generate the copies. Unlike the copy command, you do not have to specify a length for this axis. Instead, after you choose the vector, FEMAP displays one additional dialog box that asks for the Change per Repetition. You can specify both a Rotation Angle and a Translation Distance. Each copy is rotated around the axis of rotation vector by the specified angle (following right-hand rule conventions), and is translated along the axis vector by specified distance. If you specify a nonzero translation distance, you will be creating a spiral. Axis of Revolution

Spiral created by rotating with a nonzero translation distance.

One original node Circle created by rotating with translation distance set to zero.

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3.5.5 Geometry, Reflect Commands The commands on this menu allow you to generate a portion of your model by reflecting or flipping existing points, curves, surfaces, volumes, and solids across a plane. Reflection Plane 20

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As always, you will use the standard entity selection dialog box to choose the entities to be reflected. Then FEMAP will display the Generation Options dialog box. (See Section 3.5.1, "Geometry, Copy Commands"). All options work just like they do for Geometry, Copy commands, except that you cannot choose multiple repetitions.

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In addition, you can specify a Trap Width in the Generation Options dialog box. FEMAP will not make a copy of Reflected Points Original Points any selected point or curve if it is closer to the reflection plane than the trap width that you specify. If you set the trap width to zero, all of the entities that you select will be reflected. This option is used most often when reflecting elements, and will usually be zero when reflecting geometry. Next, FEMAP will display the standard plane selection dialog box, so you can define the reflection plane. You can choose any plane that you want. It does not matter how your selected entities are oriented with respect to the plane. They can be on one side, or they can be on both sides of the plane. Just remember that the reflected entities will be located on the opposite side of the plane from the original.

3.6 Modifying Geometry The last major sections of commands involve the modification of geometry. Geometry commands explained above, under the Geometry menu, were used to create new geometric entities, either from “scratch” or as some type of duplicate from existing geometry. This section deals with the actual modification of geometry, not its creation. It is often easier to modify geometry by using commands to trim or fillet curves, than it is to create the curves from “scratch” in every model. All these commands are contained under the Modify menu. These commands can be separated into four specific areas for the purpose. They are: •

curve operations (Trim, Extend, etc.)



move geometry operations



edit/parameters



advanced updates

These commands are all contained on the Modify menu. The curve operation commands are contained on the top section of the Modify menu, while the move geometry commands are contained in the middle section. The bottom section of the Modify menu contains the edit/parameters commands (Edit, Color, Layer), and the advanced updates (top portion of the Modify, Update Other menu). Each of these areas and their commands are discussed more thoroughly in the sections below.

3.6.1 Curve Operations The top portion of the Modify menu contains commands that will modify existing curves. These commands essentially perform Boolean operations on curves. Other Boolean operations are performed directly on the solids menu. The commands on the first section of the Modify menu are specifically designed to manipulate only curves. Several commands also require input of a “Near” location. When trimming or joining curves, several possible solutions may be obtained. By inputting a “Near” location, you specify which option to select. The easiest method to use this option is to position the cursor so it will select the appropriate curve, but also so it is near the proper location. When you press the mouse button to select the curve, FEMAP will automatically select the curve, and input the coordinate location in the “Near” inputs. If you make a mistake, you can always set the input back to the center location and pick new coordinates. These curve operations cannot be performed on curves that define a surface or solid. The available commands are:

Modify, Trim... •

Modify



Trim



Extend



Break



Join



Fillet



Chamfer

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Each of these commands are explained below. Note: These curve operations cannot be performed on curves that define a surface or a solid. You must delete any entities that reference these curves before you can perform any of these curve operations.

3.6.1.1 Modify, Trim...

Ctrl+i

... cuts curves at the locations where they intersect other curves. The curves you want to trim must actually intersect. This command does not project curves onto a plane before intersecting - it uses the three dimensional curve definition. To trim, you must select the curves that will be used as the cutting edges using the standard entity selection dialog box. You can choose as many cutting curves as you like.

Choosing the Curve to Trim After you choose the cutting curves, you will see the following dialog box:

You must select the curve you want to trim and define a location (Remove Near) near the portion of the curve that you want to eliminate. Assuming they intersect, the cutting curves always divide the curve that you are trimming into at least two sections, and possibly more. The portion of the curve closest to the Remove Near location you specify will be removed. This could be one of the ends of the curve, or a segment on the interior. The location must be specified relative to the coordinate system shown, but other than this, the coordinate system has no impact on this command. When you have selected the curve and location you want to trim, you can press OK or More. Choose OK if this is the only curve that you want to trim with the selected cutting curves. Press More if you want to trim more curves without selecting new cutting curves. By far, the easiest way to use this command is to use your mouse to graphically select the curve. While input is set to the ID field, point at the portion of the curve that you want to remove and click the left mouse button. This will select both the ID and the Remove Near location. If you double-click the mouse instead, it will also automatically press the OK button and trim the curve. The extended trim option controls how the cutting curves are used. With extended trim on, cutting curves extend past their end points toward infinity. Trimming intersections can be found anywhere along these extended curves. If extended trim is off, the cutting curves stop at their end points and intersections can only be found between the end points.

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Examples Curve to Trim if Remove Near is at this end

if Remove Near is at this end

if Remove Near is in the middle

Remove Near

Cutting Curve Remove Near

Curve to Trim Curve to Trim

3.6.1.2 Modify, Extend... ... moves the end points of one or more curves to a specified location. This command can either lengthen or shorten the curves depending upon the chosen location. If the location does not lie along the curve, the curve is extended along its length to the location that is closest to the coordinates you specified. This command only uses standard dialog boxes. You choose the curves to extend using the standard entity selection dialog. You then specify the location using the standard coordinate dialog boxes. As described above, any curves and any location can be chosen. The location is simply projected onto each curve at the point of closest proximity. This command always modifies the end of the curve that is already closest to the specified location. You can also use this command to extend or shrink B-Spline curves.

3.6.1.3 Modify, Break...

Ctrl+K

... splits one or more curves into two pieces at a location that you specify. If the location is not along the length of a curve, it is projected to the closest location on the curve, and the curve is split at that location. The location that you choose, or its projection, must fall within the current end points of the curve that you are trying to break. You cannot use this command to extend the existing curve beyond its end points. Only standard dialog boxes are used for this command. You select the curves to break using the standard entity selection dialog box. Then, you choose the location with the standard coordinate dialog boxes. Normally, breaking a curve does not change its type. You just end up with two new curves of the same type, that together, make up the original curve. The only exception is when you break a circle. In this case, you end up with two arcs (a different type of curve) that represent the original circle.

Modify, Join...

Original Curves

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Extended Curves Closest to specified location

Extend to here

Extend (shrink) to here

Extend to here

Examples Original Curves

Break here

Original Circle Starting location of circle

Break here

3.6.1.4 Modify, Join...

Two arcs

Ctrl+J ...combines the capabilities found in the trim and extend commands to allow you to quickly connect two intersecting curves. If an intersection is found the selected curves are either extended or shortened to that common location. This command cannot be used to create a third curve from the two selected curves. It simply extends or shrinks the

curves so they will intersect. Only one dialog box is required for this command. Here you select the two curves, and a location near the intersection where you want to join the curves. If you are joining lines, you can specify any location that you want since there will only be a single intersection. For other curve types, where multiple intersections are possible, the curves are joined at the intersection that is closest to the location you specify. The coordinate system can be used for convenience in specifying the location, but is not used otherwise. The Update 1 and Update 2 options control whether the respective curves will be extended (or shortened) to the join location. If you turn one of these off, that curve will not be updated, but the other curve will still be extended to the join location. Do not turn both off - nothing will be updated. This command cannot work, if the curves, or the extensions of the curves past their end points, do not intersect. If the selected curves intersect within their original length, the Near location is used to determine which portion of the

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curves will be kept after they are updated. Just like Modify, Fillet, the portion of the curve closest to the Near location is kept.

Examples Join these curves These portions have been removed Near

Join these curves

These portions have been removed

Near Join these curves

Only update this curve

3.6.1.5 Modify, Fillet...

Only one curve extended to join location

Ctrl+F

... connects two curves with an arc of a specified radius. The lengths of the original curves can be adjusted so that they just meet the ends of the fillet arc. The arc is positioned so that it is tangent to both original curves at its end points.

Just like the Modify, Join command, only one dialog box is required for this command. You must choose the two curves to fillet, and a location that is near the center of the desired fillet. Since even at a line-to-line intersection there are four possible quadrants for the fillet, this location is always important. It must lie in the quadrant where you want the fillet arc. For other curve types, it also chooses between the many possible intersection locations. The examples below will show you how to specify this location. If you are filleting intersecting curves, like lines, you can choose any fillet radius that you want. If you are filleting non-intersecting curves, like two arcs or circles, the fillet radius must be large enough to span the gap between the curves. As long as the Trim Curve options are on, the end points of the respective curve will be adjusted to be coincident with the ends of the fillet arc. If you just want to add an arc, but not trim the curves, turn one or more of these options off. If you are having trouble creating the arc that you want, check the location and alignment of your workplane. The coordinates that you pick are typically in the workplane and if it is skewed relative to the curves that you are filleting, the point you choose may not be in the quadrant that you expected. It is always best to do filleting in a view where the curves and the workplane are normal to the screen.

Modify, Chamfer...

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Examples Original Curves Fillet Arc

Both curves trimmed or extended to the fillet locations.

Center Near here

Pick the center location in the quadrant where you want the fillet. Pick here for this fillet

Original Curves

Original Curves

Original Curves

Fillet added without trimming original circles

Limitations You may encounter the following limitations when you are attempting to fillet curves: •

If you are going to fillet an arc, circle or spline, the other curve should lie in the same plane. If it does not, the fillet that is created will probably not be tangent to both curves, or no fillet will be created. Fillet expects the geometry to be planar.



If you attempt to fillet splines, the fillet arc will probably not be tangent to the spline. Since splines cannot be precisely offset, the center location of the fillet arc is not calculated precisely. You will have to adjust the position manually or use another technique.

3.6.1.6 Modify, Chamfer... ... trims two intersecting lines at a specified distance from their end points and connects the trimmed ends with a new line. This command is very similar to the Modify, Fillet command, but you must choose lines (not arcs, circles or splines). Just like the Modify, Fillet command, only one dialog box is required. You must choose the two lines to chamfer, and a location that is near the center of the desired chamfer. Since even at a line-line intersection there are four possible quadrants for the chamfer, this location is always important. It must lie in the quadrant where you want the chamfer line. The figure shows you how to specify this location. Curve 1

Chamfer Length 1

Choose location near here

Chamfer Length 2

Chamfer Line Curve 2

options off.

You can choose any chamfer lengths that you want, and you can independently control the chamfer length along each curve. The lengths that you specify are the distances along the curves as shown here. As long as the Trim Curve options are on, the end points of the respective line will be adjusted to be coincident with the ends of the chamfer line. If you just want to add a line, but not trim the original lines, turn one or more of these

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If you are having trouble creating the chamfer that you want, check the location and alignment of your workplane. The coordinates that you pick are typically in the workplane and if it is skewed relative to the lines that you are chamfering, the point you choose may not be in the quadrant that you expected. It is always best to do chamfering in a view where the lines and the workplane are normal to the screen.

3.6.2 Moving Geometry FEMAP also has robust tolls for moving geometry. When you move geometry, any geometry that reference that geometry is also moved. Therefore, if you move a point that is referenced by a curve on a surface, you are actually modifying that surface. These move commands, therefore, give you the power to make large scale changes to the model with only a few changes to the geometry. These commands are also very useful when assembling parts from different models into one large model. The move commands can be separated into five major categories: •

Project



Translate (Move)



Rotate



Alignment



Scale

Both the Translate and Rotate categories have two capabilities based upon whether you move/rotate to a given position (Move To and Rotate To) or move along or rotate around (Move By and Rotate By) a vector. Each of the individual commands is described in more detail below. Note: These commands cannot be used to move entities of solids. You must use the commands under the Geometry, Solids menu to perform manipulations on solid entities. You can move an entire solid, however.

3.6.2.1 Modify, Project Menu The Project commands update the locations of points by moving them onto a selected curve or surface. These commands are only used for points (or nodes with finite element data). In all of these commands, the projection direction will typically be normal to the curve or surface that you are projecting onto. Actually however, these commands move the entities to the closest location on the curve or surface. For the purposes of these commands, curves extend past their end points toward infinity, or in the case of an arc, they extend a full 360 degrees. Likewise, surfaces extend past their edge curves, but not to infinity. Even though possible, you should avoid projecting onto a surface outside of its defined boundaries. Depending on the surface type, this may or may not result in the coordinates that you expected.

Modify, Project, Point onto Curve... ... moves one or more points onto a curve. The standard entity selection dialog box is used to choose the points that you want to project. You then select the curve for the projection. You can choose any curve, and all of the selected points will be projected onto it. For more information on how the projection will be done, see Section 3.6.2.1, "Modify, Project Menu".

Modify, Project Menu

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Projected Locations

Original Locations

Points projected onto “extended” curve

Original Locations

Projected Locations

Point projected onto “extended” arc

Modify, Project, Point onto Surface... ... moves one or more points onto a surface. The standard entity selection dialog box is used to choose the points that you want to project, and then you must select the appropriate surface. You can choose any surface, and all of the selected points will be projected onto it. For more information on how the projection will be done, see Section 3.6.2.1, "Modify, Project Menu". Original Points Projected Points

Surface

Modify, Project, Point along Vector... ...similar to Modify, Project, Point onto Surface except it allows you to use a vector to specify a projection direction instead of always using the surface normal direction. This can be helpful if you are projecting points in a plane onto a surface with a high level or curvature and want to keep the spatial relationship between the points intact. FEMAP will ask if it is “OK to Project in Both Directions along Vector (No = Positive Only)?”. Clicking Yes will extend the vector in both directions, which is helpful in cases where the vector was defined in the wrong direction.

Modify, Project, Point onto Vector... ... similar to Modify, Project, Point onto Curve except it allows you to specify a vector (using any “method” in FEMAP) representing a straight line between two coordinates to “project to” instead of an existing curve.

Modify, Project, Point onto Plane... ... similar to Modify, Project, Point onto Surface except it allows you to specify a 2-D plane (using any “method” in FEMAP) to “project to” instead of an existing planar surface.

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3.6.2.2 Modify, Move To Menu The Move To commands update the location of some portion of your model. Although there are only commands to move coordinate systems, points, and nodes, you can use these commands to move your entire model. For example, when you move a point, the geometry entities (curves, surfaces, etc.) that reference the point, are also updated. The basic philosophy behind each of these commands is to specify a new coordinate to which selected entities will be moved. Since it is relatively useless to move multiple entities to a single location (they would all be coincident), each command allows you to limit the movement to any subset of the three coordinates. For example, you can just update the X coordinates, leaving all Y and Z coordinates in their original locations. By specifying a non-rectangular coordinate system, you can also move to a selected radius or angle. Each command on this menu displays the standard entity selection dialog box so you can choose the entities to move. When you press OK, the standard coordinate definition dialog box appears to specify the location to Move To. Finally, after you choose a location, you will see the Move To dialog box to select which coordinate (in a specific coordinate system) to update. Only those coordinates that are checked will be updated. In most cases, you will not want to check all three coordinates unless you are updating a single point. For example, you could use the Move To, Point command to move all nodes to be in a specific plane (i.e. same value of X). Before

After

Select all points and change X coordinates to this location.

Modify, Move To, Coord Sys... ... is the most powerful Move To command. Not only does it update the location of the coordinate systems that you select, but it can also move all points, nodes and other coordinate systems that are defined relative to those coordinate systems. If you just want to move the coordinate systems that you selected, do not choose Move CSys, Nodes and Points... If you did select that option, FEMAP would move the coordinate systems you selected plus the dependent entities. All of the coordinate systems that you select are updated as you requested. Other dependent entities are moved as a rigid body based on the transformation of the definition coordinate systems. If a coordinate system is both selected and dependent on other selected coordinate systems, it is updated based on your request, since you selected it. For more information, see Section 3.6.2.2, "Modify, Move To Menu"

Modify, Move By Menu

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CSys 3 moves and so do nodes

If your model was built in a hierarchical manner, using multiple coordinate systems, this command can quickly move large, related portions of your model. If you want to update the location of a coordinate system but leave the entities that reference it in their original positions, you can also use the Modify, Update, Coord Sys command.

Modify, Move To, Point... ... moves selected points to a specified coordinate. Curves and any other geometry that reference the selected points will also be moved. For more information, see Section 3.6.2.2, "Modify, Move To Menu".

3.6.2.3 Modify, Move By Menu These commands are similar to those found on the Move To submenu. The significant difference is that for these commands you specify a vector instead of coordinates. All of the entities that you select for modification are moved along (or by) that vector. This command only uses two dialog boxes. First, the standard entity selection dialog box is displayed. You should select the entities to be updated. Then, the standard vector definition dialog box will be displayed. The vector you specify must contain both a direction and magnitude. All of the selected entities, and the entities that reference them will be moved by that vector. This essentially means that the location of the selected entity is updated by adding the components of the vector. Move By vector

Select these nodes

Move By in Non-Rectangular Coordinate Systems The Move By commands always move along a vector (i.e. along a straight line). You can define the vector in any convenient coordinate system, but it will always represent a straight line. You can not use the Move By commands to rotate your model by specifying a vector in the angular direction of a cylindrical coordinate system. Use the Rotate commands to rotate your model.

Modify, Move By, Coord Sys... ... just like the Modify, Move To, Coord Sys command, will move all of the selected coordinate systems, and any points, nodes, or other coordinate systems that reference a selected system. This can be very powerful if your model is constructed with multi-level coordinate systems. Again, dependent entities are moved as a rigid body. Selected coordinate systems are all moved by the vector that you define. For more information, see Section 3.6.2.3, "Modify, Move By Menu".

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Modify, Move By Point, Curve, Surface, Volume, Solid... ... moves the selected points, curves, or surfaces and all geometry that references them, by the specified vector. For more information, see Section 3.6.2.3, "Modify, Move By Menu". When you move points that are connected to curves, those curves will be moved also. If you only move some of the points which are attached to a curve, the shape and size of the curve will probably change. Be especially careful when moving points that define arcs or circles. Small movements can sometimes lead to large changes in the curve definition.

Modify, Move By, Point;

Modify, Move By, Surface;

Modify, Move By, Solid

3.6.2.4 Modify, Rotate To Menu The commands on this menu rotate selected entities. Unlike the Modify, Move To commands, these commands treat the selected entities as a rigid body. All of them are rotated by the same angle. The Modify, Rotate To commands require four dialog boxes. First, the standard entity selection dialog box is displayed. You can select all of the entities that you want to rotate. Then, the standard vector definition dialog box defines the axis of rotation. Only the location of the base and the direction of this vector are important. The length is not used. Finally, the standard coordinate definition dialog box is displayed twice. The first time, you must define the coordinates of the starting point of the rotation. The second time, you must define the ending point of the rotation. Using these coordinates, and the axis of rotation, FEMAP will determine the rotation angle. Axis of rotation

Rotate to here

Rotate from here

Modify, Rotate To, Coord Sys... ... just like the Modify, Move commands, will rotate all selected coordinate systems. Points and other coordinate systems that reference a selected system are also moved as a rigid body. Their movement is based on the motion of their definition coordinate systems. This can be very powerful if your model is constructed with multi-level coordinate systems. For more information, see Section 3.6.2.4, "Modify, Rotate To Menu".

Modify, Rotate To Point, Curve, Surface, Volume, Solid... ... rotates selected geometry, and all other geometry that references them, around the specified vector. For more information, see Section 3.6.2.4, "Modify, Rotate To Menu".

Modify, Rotate To, Point;

Modify, Rotate To, Surface;

Modify, Rotate To, Solid

3.6.2.5 Modify, Rotate By Menu These commands are similar to the commands on the Modify, Rotate To menu but you must specify a rotation angle instead of locations. You can also specify an optional Translation Distance with these commands. By combining both rotation about, and translation along the axis of rotation, you can move entities along a “screw-thread” or helix shaped path.

Modify, Align Menu

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Simply select the entities, chose a vector, and define the Rotation Angle and the Translation Distance.

Axis of rotation

The selected entities will be rotated (following right-hand rule conventions) around the axis of rotation by the specified angle. Simultaneously, they will be translated, along the same vector, by the specified distance. The actual length of the vector is not used. If you specify a zero rotation angle, these commands will simply translate along the vector - much like the Modify, Move By commands.

Modify, Rotate By, Coord Sys... ... just like the Modify, Rotate To commands, will rotate all of the selected coordinate systems. Points or other coordinate systems that reference a selected system are also moved as a rigid body. Their movement is based on the transformation of the selected coordinate systems. This can be very powerful if your model is constructed with multi-level coordinate systems. For more information, see Section 3.6.2.5, "Modify, Rotate By Menu".

Modify, Rotate By Point, Curve, Surface, Volume, Solid... ... rotates the selected points, and all geometry that references them, around the specified vector. For more information, see Section 3.6.2.5, "Modify, Rotate By Menu" When you rotate points that are connected to curves, those curves will rotate also. If you only select some of the points which are attached to a curve, the shape and size of the curve will probably change. Be especially careful when rotating points that define arcs or circles. Small movements can often lead to large changes in the curve definition.

Modify, Rotate By, Point;

Modify, Rotate By, Surface;

Modify, Rotate By, Solid

3.6.2.6 Modify, Align Menu These commands combine the capabilities of the Modify, Move and Rotate commands to provide a simple way of aligning portions of your model. Only three dialog boxes are necessary.

To this vector, along these other elements Aligned elements

From this vector

Align these elements

First, you select the entities that you want to align using the standard entity selection dialog box. Next you need to specify two vectors using the vector definition dialog boxes. The first vector defines the original position and orientation that will be aligned. The second vector defines new or desired position and orientation. FEMAP will first move the entities that you selected from the origin of the first vector to the origin of the second vector. Then, FEMAP will rotate the entities to the new orientation. This is accomplished by a rotation based on the angle between the vectors.

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Geometry

If you simply want to use this command as an alternate method of rotation, make sure both vectors have the same origin. If you do not, the entities will be translated before they are rotated Modify, Align by CSys... ... is just like the Move and Rotate commands. It will align all of the coordinate systems that you select, plus the entities that are defined relative to those systems. No option is available to skip alignment of the referencing entities. Modify, Align Point, Curve, Surface, Volume, Solid... ... aligns the selected geometry, and all geometry that references them, using the two vectors. For more information, see Section 3.6.2.6, "Modify, Align Menu".

3.6.2.7 Modify, Scale Menu These commands are used to change the size of your model. You specify a relative scaling factor and a point to scale around. FEMAP will adjust the selected coordinates appropriately. Like other modification commands, entities which reference the selected entities which you have selected to scale will also be scaled. Coordinate systems cannot be scaled. The first dialog box used by these commands is the standard entity selection dialog. You must select all of the entities that you wish to scale. After you press OK, FEMAP will display the standard coordinate definition dialog box. FEMAP will scale your model relative to these base coordinates. The equation used for the scaling is: { X } New = { X } Old + ( ( { X } Base – { X } Old ) × { X } ScaleFactor )

Finally, FEMAP displays the Scale dialog box which requires input of a coordinate system as well as scale factors. You can specify three different scale factors, one for each coordinate direction. For any coordinate direction that you do not want to scale, you must use a scale factor of 1.0. Scale factors that are larger than 1.0 increase the physical size of your model. Scale factors smaller than 1.0 decrease its size. You can use a negative scale factor to reflect the entities about the base location. Similarly, a scale factor of 0.0, will move all entities to the base coordinate, just like the Modify, Move To commands All scaling is done in the coordinate system that you select. The coordinate directions are along the axes of this system. If you select a non-rectangular system, you can scale your model radially or tangentially. Original Model

After Scale Factor of 2.0 in Horizontal Direction Only

3.6.3 Edit/Parameters The first three commands in the third section of the Modify menu (Edit, Color, and Layer) enable you to change specific items in the geometry. Each of these commands are described below.

3.6.3.1 Modify, Edit Commands The commands on the Modify, Edit menu are used to edit or “recreate” entities in your model. These commands are typically used when you need to perform modifications to a single or a few entities. You will be prompted for input for each entity selected. Therefore, to use this command to modify hundreds of entities, can be quite time consuming. For these type of gross changes to the model, please see the other Modify commands in this section of the Modify menu (Color, Layer, Update Elements and Update Other commands). For geometry, this command can only be used to modify points and surface boundaries (and coordinate systems). Each command first asks you to select the entities you wish to edit. As always, the standard entity selection dialog box is used. Following your selections, FEMAP simply displays the same dialog box (or boxes) used by the related command in the Geometry menu which you used to originally create the entities. In this case however, all of the

Modify, Color Commands

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data fields default to the current values for the selected entities. For example, if you choose Edit Point and then select points 1, 3 and 5, three additional dialog boxes will be displayed, one at a time. The first dialog box will display the coordinates of point 1. You can change them, or just press OK to accept the current values. Then dialog boxes for points 3 and 5 will be displayed. If you press Cancel at any time, you will immediately return to the FEMAP menu. Any entities that you had previously changed (and pressed OK) will still be changed.

3.6.3.2 Modify, Color Commands The commands on this submenu are used to modify the color of one or more selected entities of a specific type. All of these commands work in a similar fashion. Each of these commands uses the standard entity selection dialog box to select the entities to be modified. Then the standard Color Palette dialog box is displayed. You can pick a color, which will be applied to all of the entities that you selected. The default color, will be the current color of the selected entity with the minimum ID. For more information on the Color Palette, see Section 4.3.5, "Color Palette" of the FEMAP User Guide. You can also use the Modify, Edit commands to change colors, but these commands will be much quicker if you are changing multiple entities to the same color.

Modify, Color, Point;

Modify, Color, Curve;

Modify, Color, Solid;

Modify, Color, Coord Sys

Modify, Color, Surface

3.6.3.3 Modify, Layer Commands The commands on this submenu are used to modify the layer of one or more selected entities of a specific type. These commands are very much like those on the Modify, Color menu. First, you select the entities you want to modify using the standard entity selection dialog box. Then, instead of selecting from the Color Palette, FEMAP will prompt you to choose a new layer number from the list of available layers. All of the selected entities will be modified to the specified layer. Again, Modify, Edit can be used to change layers, but this command is faster for multiple entities.

Modify, Layer, Point;

Modify, Layer, Curve;

Modify, Layer, Solid;

Modify, Layer, Coord Sys

Modify, Layer, Surface

3.6.3.4 Modify, Renumber Menu The commands on this submenu are used to renumber the IDs of one or more selected geometry (points, curves, surfaces, volumes and solids). Each of these commands uses the standard entity selection dialog box to select the entities to be renumbered. After you press OK, the Renumber To dialog box is displayed. You select a new Starting ID and Increment. The first entity to be renumbered is changed to the starting ID. The increment is then added to the starting ID before each subsequent entity is renumbered. Refer to Section 4.8.2.5, "Modify, Renumber Menu" for more information.

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Geometry

Modify, Renumber, Point;

Modify, Renumber, Curve;

Modify, Renumber, Solid;

Modify, Renumber, Coord Sys

Modify, Renumber, Surface

3.6.4 Advanced Updates - Modify, Update Other Commands The commands on this menu are used to update parameters which are referenced by one or more selected entities. Unlike the commands on the Modify, Color and Modify, Layer menus, the parameters that are updated by these commands are only applicable to one entity type. All of these commands work in a similar fashion, but since the parameters that they update vary, each command is documented in its own section.

3.6.4.1 Modify, Update Other, Point Definition CSys... ... works just like Modify, Update CSys, Definition CSys, except that you select points to update instead of coordinate Systems. If you want to create a new coordinate system while using this command, simply click the “Coordinate System” Icon Button in the Select Coordinate System... dialog box.

3.6.4.2 Modify, Update Other, BSpline Order... ... is used to change the order of B-Spline curves. B-Spline curves created in FEMAP will automatically default to an order of 3. Higher order splines can provide some shape smoothing, but may also cause sharp fluctuations for splines that have been driven through particular points. This command should be used with some care in these circumstances. The maximum order for any B-Spline is either the number of points (a mathematical limit) or ten (a FEMAP limit), whichever is smaller.

3.6.4.3 Modify, Update Other, BSpline Knots... ... is used to insert control points on the selected B-Splines. This command provides you with a powerful tool to modify the curvature and smoothness of a particular curve by inserting control points at precise locations. You simply select the curve(s) to update and then enter the location of the Knot (control point).

3.6.4.4 Modify, Update Other, Reverse Curve... ... enables you to reverse the direction of a curve. This command cannot be used on any curves that are referenced by surfaces, therefore no solid curves can be reversed. This option can be useful when creating curves to model entities that require a certain direction of the curves (for example, curves for an ABAQUS rigid surface). The only input to this command is the curves to reverse.

3.6.4.5 Modify, Update Other, Nonmergeable Curve... ... allows you to designate curves as “non-mergeable”, meaning the curves will not be “merged” into a surface or solid and deleted during a clean-up operation. Clean-up operations will often occur as a part of stitching a solid, performing certain solid boolean operations, or using the Geometry, Solid, Cleanup command. This command can also be used to move “split-points” on fully circular curves to more desirable positions. In order for this to be effective, manipulate the curves until the break points are positioned, designate the curves as “non-mergeable”, then use the stitch, boolean, or clean-up commands to have the new positions be used for split lines in a feature (i.e. a hole).

3.6.4.6 Modify, Update Other, Boundary on Surface... ... is used to map a boundary surface, which is typically planar, onto a surface. This command enables you to provide curvature to any boundary surface. When you select this command, you will be asked if it is OK to map onto a surface. If you say Yes, you must then select the surface and the boundary will be mapped to it. If you say No, any connections to a surface which the boundary had previously are removed. Therefore, you can use this command to either attach a boundary surface to a surface, or remove a connection.

3.6.4.7 Modify, Update Other, Surface Normal... ... is used to reverse the normal of sheet solids. To begin, you simply select the sheet solid where you want to reverse the normal, using the standard entity selection dialog box. Then FEMAP will reverse the surface normal without further user input. This command works on solid surfaces only.

Modify, Update Other, Solid Facetting...

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3.6.4.8 Modify, Update Other, Solid Facetting... ... can be used to specify parameters in FEMAP which will control the number of facets on solids in your model. The values which appear in the Update Solid Facetting dialog box are the default values for facetting. Angle Error is a measure of the angle between the tangent of each facet at the point it touches the edge of the solid and the chord of each facet. Chord Error is a measure of the length of the chord of each facet to the distance it is away from the edge of the solid at the middle of the chord. Curve Factor is used to improve the curve accuracy of attached curves to the surfaces. Essentially, FEMAP takes the values specified for solid facetting and changes the curve accuracy to be the Curve Factor value times more accurate. This allows you to create very accurate curve representations without having to drive the solid facetting up to far, which could impact performance. The Cross Hatching options allow you to specify the number of cross-hatching lines will be seen on each surface of the solid when in Wireframe mode. To improve performance, you may want to raise the values of Angle Error and/or Chord Error, while making them lower will improve facet accuracy to the geometry.

3.7 Deleting Geometry The commands on the Delete, Geometry menu are all used to delete entities. All commands will delete entities from your model. Since most of the commands on this menu work in a very similar fashion, the documentation for the entire menu is given in this section.

Deleting From Your Model If you want to delete any type of entity in your model, all you need to do is select the appropriate command (based on the entity type) from this menu. The standard entity selection dialog box will then be displayed to let you select the entities you wish to delete. When you complete your selection, and press OK, you will be asked to confirm that you really want to delete the entities. This final question will also let you know how many entities have been selected. Answering Ye, will delete the entities. Choosing No will simply cancel the command. You may also use the Delete, All or Delete, Geometry All command to remove all geometry from the model. When you choose this command, FEMAP will ask you to confirm that you really want to delete all geometry (and analysis model if you select Delete All). If you answer Yes, all geometry will be removed from the model. If you answer No, the command is canceled. The Delete, Geometry All command is useful for removing geometry from a meshed model when it is no longer of use (assuming you do not want to constrain or load geometry). No checking is performed to see if any entities are considered non-deletable since all geometry is removed.

Non-Deletable Entities Sometimes when you try to delete, you will receive a message that a number of non-deletable entities have been skipped. These entities are skipped because FEMAP protects you from deleting entities which are needed by other entities in your model. For example, a point is non-deletable if it is connected to one or more curves. Similarly a curve is non-deletable if it has a load attached to it. To delete these non-deletable entities, you must first delete all of the entities which reference them.The following table lists the entities that can cause an entity to be non-deletable: When you are trying to delete... Point Curve Surface

Hint:

Could be referenced by... Curves, loads, (solids) Surfaces, loads, (solids) Solids, volumes, surfaces, curves, loads

You can use this feature to great advantage in “cleaning up” a model. For example, if you want to get rid of all of the unused points, simply choose Delete, Point, and select all points. This may seem dangerous, but in fact only those points which are not referenced by any other geometry or loads will be deleted. If you attempt to delete an entity, and FEMAP says it is non-deletable, and you believe that there are no connections to it, perform a File, Rebuild. This will check all connections in the model, and verify whether there are connections to this entity.

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Geometry

Deleting Geometry Icons Delete, Geometry, Point...;

Delete, Geometry, Curve...;

Delete, Geometry, Solid...;

Delete, Model, Coord Sys...

Delete, Geometry, Surface...

After You Delete When you delete entities from a FEMAP model, the space that they occupied is simply marked as empty and available for reuse. The model file does not decrease in size. Normally, as long as you are going to create additional data, this is not a problem since the space will be reused. In some cases however, when you delete a lot of data you may want to immediately remove that empty space from your model and reduce the size of your model file. The File, Rebuild command can do just that. Choose the File, Rebuild command, then press Yes to perform a full rebuild and compact the model. If you had blocks of empty space, they will be removed and your model will decrease in size. You should only use this option after you delete large blocks of data (i.e., Output). FEMAP cannot usually compact space if you have only deleted one or two scattered entities, and the savings will not be worth the time it takes to perform the command.

4.

Finite Element Modeling The Model menu provides the basic commands for creating finite element information in your model. It also lets you set up an analysis case for certain solvers. This topic describes how to use the sub-menus and commands under the Model menu. It includes these sections: •

Section 4.1, "Creating Coordinate Systems" (Coordinate systems are separated from the finite element information in this structure because they are applicable for both geometry and finite element information.)



Section 4.2, "Creating Finite Element Entities" (on the Model menu)



Section 4.3, "Creating Loads And Constraints" (on the Model menu)



Section 4.4, "Creating Connections and Regions" (on the Connect menu)



Section 4.5, "Creating Aeroelastic Entities" (on the Model menu)



Section 4.6, "Using Optimization Analysis" (on the Model menu)



Section 4.7, "Working with Functions" (on the Model menu)



Section 4.8, "Modifying FEA Entities" (on the Modify menu)



Section 4.9, "Deleting FEA Entities" (on the Delete menu)



Section 4.10, "Preparing for Analysis" (on the Model menu)

For information on the Model, Output sub-menu, see Section 8.5, "Output Manipulation".

4.1 Creating Coordinate Systems Coordinate systems are applicable for both finite element information and geometry. In general, coordinate systems can greatly simplify input to your model. They are also a convenient way to update the position of geometry and finite elements. If you use the Modify, Move commands to move coordinate systems, all geometry defined in that coordinate system will move with it - even other coordinate systems. In this manner, you can create a hierarchy of coordinate systems which greatly simplify movement of geometry. The methods of creating coordinate systems are explained below.

4.1.1 Model, Coord Sys... ... allows you to define coordinate systems for coordinate, vector or plane entry or to align nodal degrees of freedom or material axes. Coordinate Systems 0 (Global Rectangular), 1 (Global Cylindrical), and 2 (Global Spherical) are always defined. You can create any additional coordinate systems that you need for your model with this command. When you choose this command you will see the Define Coordinate System dialog box, which allows you to define numerous parameters which determine the type of coordinate system to be created. ID, Title, Color/Palette and Layer These options set parameters for the coordinate system to be created. Titles can be up to 79 characters long. Ref CSys The coordinate system you create will be defined in this coordinate system. This will also be the default coordinate system for coordinate or vector definition - although you can change that system when those dialog boxes are displayed. The reference coordinate system is utilized to create a hierarchy of coordinate systems which can be used in later Modify, Move commands.

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Finite Element Modeling

Type Determines the type of coordinate system that will be created. Coordinate specification for each of the types is shown in Section 4.3.2, “Coordinate Definition” in the FEMAP User Guide.

4.1.1.1 Angles Method of Creating Coordinate Systems... ... allows you to specify coordinates using the standard coordinate definition dialog boxes to define the coordinate system origin. The orientation of the coordinate system is then specified by three rotation angles, around the reference coordinate system directions. All angles are entered in degrees. Rotations about multiple axes are interpreted as a rotation about the reference coordinate system X-axis, then the rotated Y-axis and finally the rotated Z-axis, as shown here. Z

Z θ y’

z’ y’

x’

x’’

Y

rotate around x

X

y’’

z’’

θx

X

Z

Y

then around rotated y

y’’’ z’’’

θz’’ X

x’’’ Y

then around doubly rotated z

4.1.1.2 Workplane Method of Creating a Coordinate System This method of creating a coordinate system simply creates a coordinate system by placing the X-Y axes at the XY axes of the current workplane. The Z axis is created as the positive normal to the workplane. Since this command uses the current workplane, no additional input is required.

4.1.1.3 Coordinates Method of Creating a Coordinate System Z

Origin

y

z X Axis

XY Plane

x

Y X

There are three methods to create a coordinate system using coordinate locations. Each of these methods requires you to define three sets of coordinates using the standard coordinate definition dialog boxes. The first set of coordinates defines the coordinate system origin. The final two sets orient the coordinate system axes. The methods are titled XY Locate, YZ Locate, and ZX Locate. These names correspond to the orientation axes that you define. For example, for XY Locate, you specify coordinates on the X axis and coordinates in the XY plane. The final axes are calculated from the three locations that you define.

Axes Methods of Creating Coordinate Systems

4-3

4.1.1.4 Axes Methods of Creating Coordinate Systems Z

y

z

X Vector

XY Plane

x

X

Y

Just like the Locate methods, the Axes methods require three inputs. Again you specify coordinates for the origin. Then instead of locations on the axes, you specify vectors in the direction of the axes, using the standard vector definition dialog boxes. The methods are titled XY Axes, YZ Axes, and ZX Axes, which correspond to the orientation axes that you define. Again, just like for XY Locate, for XY Axes, you specify a vector along the X axis and a vector in the XY plane. Hint:

Always specify meaningful titles. They are shown along with the ID in the drop-down list boxes used for selection throughout FEMAP.

Note: In general, you can use any convenient method of entering the coordinates or vectors to define coordinate systems. However, you can not enter colinear or coincident coordinates or vectors, since they would not fully specify the coordinate system orientation.

4.2 Creating Finite Element Entities These commands allow creation of finite element entities for your model. There are five commands contained under this section: Node, Element, Material, Property, and Layup. These commands are grouped together because four of these entities (all except Layups) are normally required to create a finite element in FEMAP. The relationship between these five entities is described below: •

Node - define physical position of element in space (See Section 4.2.1, "Model, Node...")



Element - references nodes and property. (See Section 4.2.2, "Model, Element...")



Material - contains physical parameters of material. (See Section 4.2.3, "Model, Material")



Property - contains physical characteristics and references a material. (See Section 4.2.4, "Model, Property...")



Layup - contains physical characteristics of plies for laminate properties. (See Section 4.2.5, "Model, Layup...")

These commands allow you to create these entities one at a time. Many times it is much easier to use the automatic meshing tools available under the Mesh menu to generate nodes and elements for the model. In this case, you can generate your individual properties, materials, and layups with these commands, then use the automatic meshing tools to create the finite element mesh.

4.2.1 Model, Node...

Ctrl+N

... allows you to define nodes by entering their coordinates using the standard coordinate definition dialog boxes. Just like all other coordinate locations, you may use any of the available methods and/or snap modes, along with keyboard or mouse input to define the location of a node. Even so, this command creates nodes one at a time. Much more powerful methods are available through the various Generate commands.

Specifying Node Parameters When you are creating a node, choosing the Parameters command button will display the Node Parameters dialog box. The use of output coordinate systems and permanent constraints varies substantially between various analysis programs. For more information on how these features are supported for your program, see Section 8, "Analysis Program Interfaces" in the FEMAP User Guide. Output Coordinate System Here you can set the output coordinate system for the node. This is the coordinate system in which displacements, degrees of freedom, offset connections for line elements and constraints are defined. Increment, Color, Palette, Layer The Increment is added to the Node ID, which you create to determine the default ID for the next node to be created. The Color and Layer options define these parameters for the node to be created.

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Finite Element Modeling

Superelement ID The Superelement ID can be set for each node using this field. The Superelement ID is the only method available to define “Superelements” for Nastran in FEMAP. Type This option is almost always set to Node. You can change this option to Scalar Point or Extra Point for other node types, but this is not used for most analysis programs. Permanent Constraints Permanent constraints, like other constraints are defined relative to the output coordinate system. Unlike constraints that can be defined in multiple sets, there is only one group of permanent constraints per node. The six degrees of freedom which can be constrained are the X, Y and Z translations (TX, TY, TZ) and the X, Y and Z rotations (RX, RY, RZ). The permanent constraints are combined with the constraint sets that you request for analysis.

4.2.2 Model, Element...

Ctrl+E ....displays one of the element creation dialog boxes based on the active element type. You can set the active element type from any of the element creation dialog boxes (or any of the property creation dialog boxes) by choosing the Type button. This will display the Element/Property Type dialog box, where you can choose the type of elements to create. There are four main element types which often have to do with the shape or topology of elements •Line Elements (See Section 4.2.2.1, "Line Elements") •Plane Elements (See Section 4.2.2.2, "Plane Elements") •Volume Elements (See Section 4.2.2.3, "Volume Elements") •Other Elements (See Section 4.2.2.4, "Other Elements") For any of the plane or volume elements, other than Plot Only, you can choose the Parabolic Elements option to create elements with nodes at the middle of each edge. For other element types, you can only create linear elements - nodes at the corners only. For details on the full FEMAP element library, see Section 6, "Element Reference" in the FEMAP User Guide. For further information on how each element type is translated to the various analysis programs, see Section 7, "Translation Tables for Analysis Programs" in the FEMAP User Guide. You should review those sections prior to creating elements. This will ensure that you choose the correct element types to represent your structure, and element types that are supported by your analysis program.

Model, Element...

4-5

Element Material Orientation For planar and axisymmetric elements, you can also define an element material orientation. Pressing this button will display an additional dialog box that lets you set the material orientation direction or angle for all elements that are created until you change to a different orientation. This includes elements that are created using the various generation techniques. For more information, see Section 4.8.3.13, "Modify, Update Elements, Material Angle...". Proper specification of material angles is extremely important if you are using nonisotropic materials. . . Formulation If you are exporting to NASTRAN, ABAQUS, LS-DYNA, ANSYS, or MARC, you should also select the element formulation. These programs have several different subtypes, or formulations, for the same basic element. When you select Formulation..., the Element Formulation dialog box will appear. You will be able to set options for NASTRAN, LS-DYNA, ABAQUS, ANSYS, and MARC. The inputs to the dialog box will be slightly different based upon the current element type, but all element types will have separate inputs for NASTRAN, DYNA and ABAQUS/MSC.MARC/ANSYS. The element formulation for LS-DYNA is exported on the *SECTION cards as part of the property definition, while most options for ABAQUS and MSC.MARC change the name/number of the element. Each element type has a different formulation which is stored as a global variable. Once the formulation is set, all elements of that type created from that point on will have that formulation. To change to a different formulation for future meshes, simply enter the element formulation dialog box with the appropriate element type active, and select from the available options . . . . Note: If you do not set the formulation before meshing, or would like to change the formulation, you can use the Modify, Update Elements, Formulation command to change the formulation of a few elements, or an entire mesh. To determine which formulation is best for your analysis, consult your analysis program documentation. For instance, the hybrid option in ABAQUS and MARC is typically used for large elastic (hyperelastic) materials. For more information on the different available formulations, see Section 6, "Element Reference" in the FEMAP User Guide. Each element has a section on their formulations.

Common Features of All Element Dialog Boxes There are quite a few different dialog boxes used for creating the various element types in FEMAP. The major difference between them is the changing number of nodes required to define the various element types. Most other features are identical. Near the top of each dialog box, you will notice a group of controls which are used to set var-

4-6

Finite Element Modeling

ious parameters for the element to be created. The Type button, used to choose a new element type can be found here also.

ID, Color/Palette and Layer: These options set parameters for the element to be created. Every time you create an element, the default ID will be automatically incremented. Property: This drop-down list allows you to choose the property to be referenced by the element. A few element types (plot, rigid, etc.) do not require a property, but most do. For your reference, all properties that are defined in your model will be shown in the list. You must choose one which is of the same type as the element that you are creating. You can make your choice by typing an ID, choosing from the list, or by graphically selecting an existing element which references the property that you want. If you do not specify a property (leave the option blank or 0), when you press OK, you will be given a chance to automatically create a new property. You can also create a new property by click the Property “icon button” next to the Property drop-down list. This is the same as using the Model, Property command, except that the Define Element dialog box is still visible and the resulting property ID will automatically be entered into the list.

Selecting Nodes for your Elements No matter what element type you use, you will see text boxes which allow you to select the nodes to define the element. The number of these boxes corresponds to the number of nodes required for the type of element which you are creating. You can choose nodes either by typing an ID or by selecting a node from any graphics window with the cursor. Alternatively, you can leave one or more of the node IDs blank (or 0). When you press OK, you will be given a chance to automatically create new nodes for each of the blank entries. Using this technique, you can effectively create elements using specific coordinates, without having to first create nodes. The order of the text boxes in the dialog box matches the order of nodes shown for the various FEMAP element types. You should try to specify the nodes in their proper sequence. For example, for plane elements, the required nodes proceed either clockwise or counter-clockwise around the corners of the element (followed by the midside nodes for parabolic elements). You should enter the nodes in this order. Every time you create an element however, FEMAP checks its shape. If you do specify the nodes in a different order, FEMAP will attempt to reorder them so that they result in the shape you were trying to create. This technique can untwist planar elements, and switch faces on solid elements. You will receive a warning if FEMAP had to change the order. Some element types require you to specify a shape, in addition to the nodes. For plane elements, you must choose either a triangular or quadrilateral shape. For volume elements, your choices are a brick, wedge or tetrahedron. As you change the shape, you will see the number of required nodes change also. Because of the automatic node creation feature described above, you can not define a triangle with the shape set to quadrilateral and then only entering three nodes. If you try this, FEMAP will ask you to create the fourth node. Parabolic plate and solid elements allow you to pick nodes at the midsides of each element edge in addition to the corner nodes. You can however skip the midside nodes by leaving them as blank or 0. For this reason, the automatic node creation feature can only be used with the corner nodes of parabolic elements, not with the midside nodes.

4.2.2.1 Line Elements All line element types (Rod, Tube, Curved Tube, Bar, Beam, Link, Curved Beam, Spring/Damper, DOF Spring, Gap, and Plot) connect two node points. Proper choice of the type depends upon the structural behavior that you want to represent. For all of these elements, however, you will see one of two possible dialog boxes. The first, and simplest, creates all elements except the bar, beam, and curved beam. In addition to the standard parameters, it just requires two nodes to define the element. For the bar, beam, and curved beam however, you will see a more complex dialog box. This dialog also requires two nodes, but lets you define element offsets, orientation and releases.

Line Elements

4-7

Note: The number of inputs in the Define SPRING/DAMPER Element dialog box changes depending on the Type specified for the Spring/Damper property currently selected in the Property drop-down list. When the Type is set to CBUSH, there are additional inputs for Orientation and Offsets. When the Type is set to Other (NASTRAN CROD/CVISC), the dialog box simply asks for two nodes. Xe

Ze

Plane 2 (XZ)

B

Offset B Cz

2 Ye

A Plane 1 (XY)

Third Node, or Orientation Vector

Cy

Bar / Beam Elements

Offset A 1

Offsets: Offsets are used to move the end of the element a specified distance from the node. The End A and End B command buttons will display the standard vector definition dialog boxes to let you define the offset at each end of the element. Both the magnitude and direction of this vector are used to define the offset. If the element has a constant offset at both ends, you can simply define the offset at End A, then press End B=End A to copy the offset to End B. If you have already defined offsets, and want to delete them, press No Offsets. When offsets have been defined, the titles of the End A and End B buttons will change to End A... (On) and End B... (On) to reflect the status. By default, after you define an element with offsets, the next element will use the same offsets. You can turn them off with No Offsets. Checking the Use Reference Point box will offset the nodes at both ends of the element to the location of the specified Reference Point selected in the Beam Property - Cross Section Definition dialog box.

Orientation: Each of these element types requires that you orient the cross section of the element. The element X axis is always along the length of the element (between the nodes). The orientation defines the Y and Z axes. FEMAP provides two methods of orientation. You can either specify another node or a vector. If you specify an Orientation Node, the element XY plane will be defined by the element X axis and the vector from the first element node to this orientation (or third) node. If you specify a vector orientation, that vector, along with the element X axis will define the XY plane. You can enter the orientation node directly into the dialog box, or choose the Vector Orient command button to orient using a vector. The standard vector definition dialog boxes are used. If you attempt to specify both a vector and an orientation node, only the orientation node will be recognized. When you define a vector, FEMAP will update the button title to Vector Orient... (On) to reflect the status. The default orientation is the same as the orientation that you specified on the last element that you created. Releases: In some cases you do not want an element to be structurally connected to all six degrees of freedom at each node. You can choose the Releases command button to specify the degrees of freedom that you do not want to connect. By default, all degrees of freedom are connected. The Element Releases dialog box lets you choose the translational (TX,TY,TZ) and rotational (RX,RY,RZ) degrees of freedom to release at each end of the element. When you specify releases, FEMAP changes the button title to Releases... (123456/123456), or some variation of those numbers. The numbers one through six correspond to the six elemental degrees of freedom (TX, TY,..., RZ). The numbers before the slash represent the releases on the first end of the element. The numbers after the slash represent the second end. Just like offsets and orientations, FEMAP remembers the releases that you define and uses them as the defaults for your next element.

4-8

Finite Element Modeling

4.2.2.2 Plane Elements Standard Plane elements are created using one of two dialog boxes depending on whether you are creating linear or parabolic elements. The only difference between these two boxes is the addition of midside nodes for the parabolic elements.

For either of these dialog boxes you must choose either a triangular or quadrilateral shape. As you choose the shape, the number of required nodes will also change. For parabolic plate elements, midside nodes can be specified, but they can also be blank. This feature allows elimination of some elemental degrees of freedom and can be used to join linear and parabolic elements, or for transitioning between varying mesh densities. Since midside nodes are not required and the automatic node creation feature only works for required nodes, you must specify an existing node or it will be left blank. If the plane element you are creating is a Axisymmetric Shell then the dialog boxes will be more like the line element.

Axisymmetric Shells are defined as lines with two nodes for linear and a third midside node for a parabolic type. Offsets can also be defined for the shells.

4.2.2.3 Volume Elements Just like plane elements, volume elements use one of two dialog boxes depending on whether you are creating linear or parabolic elements.

Also, just like plane elements, you must specify a shape (Brick, Wedge, Tetra) and parabolic midside nodes can be skipped.

4.2.2.4 Other Elements Masses The mass and mass matrix element types require no input other than a single node to locate the element.

Stiffness Matrix Stiffness matrix elements connect two nodes and use the same dialog box described above for the simpler line elements.

Other Elements

4-9

Rigid and Interpolation Rigid and Interpolation elements are different than other types. Typically, these elements have the degrees-of-freedom (DOFs) of a single node connected or related to the DOFs of a number of other nodes. A less commonly used “connection” element, the RBE1, can also be created using this element type. Also, a different type of connection element, called an RSPLINE, can be created using a formulation. The RSPLINE is for Nastran solvers only. The dialog box contains a “tab” for each distinct type of rigid or interpolation element. The names of the tabs correspond to the names of the Nastran bulk data entries which will be created upon export. Some common controls seen on various tabs are: Use the DOF check boxes to choose which DOFs of the nodes selected using the Nodes button should be included in the appropriate Independent or Dependent list. You may use the process of specifying DOFs, then selected nodes as often as required to define an element. Use the Delete button to remove any number of entries in the multi-select list or the Reset button to remove the entire list. Update can be used to update the DOFs (RBE1 and RBE3) and/or Factor for all highlighted nodes in a list (RBE3 only). RBE1 Defines a rigid element which is connected to an arbitrary number of nodes. Specify DOFs and select nodes for both the Dependent and Independent sections.

There is a stipulation for RBE1 elements. The total number of DOFs for the Independent section MUST equal six. For example, both these would be valid: 6 nodes - T--Z DOF (DOF 3) only on each node. All 6 nodes could each have a different DOF specified as well. 4 nodes - TXYZ DOF on Node “A”, T--Z DOF on Node “B”, T-Y- DOF on Node “C”, and T--Z DOF on Node “D”.

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Finite Element Modeling

RBE2 Defines a rigid element with a single Independent node which is rigidly connected to the DOFs and Nodes specified in the Dependent section.

You must specify at least one degrees of freedom to be rigidly connected between the Independent node and the Dependent nodes. The DOFs are the same between the Independent node and ALL Dependent nodes If you would like FEMAP to create a new node at the “center” of all the selected Dependent nodes based on the coordinates of the selected nodes, choose the New Node At Center option in the Independent section. This is a helpful option when creating a “spider” rigid element at the center of a hole.

Other Elements

4-11

RBE3 Interpolation elements are used to define the motion at the Dependent node as the “weighted average” of the motions at the Independent nodes.

For interpolation elements, you may specify one set of DOFs for the Dependent node, then specify different DOFs and a Factor for each Independent node. If you would like FEMAP to create a new node at the “center” of all the selected Independent nodes based on the coordinates of the selected nodes, choose the New Node At Center option in the Dependent section. The UM DOF button displays the Define Rigid Element UM DOF dialog box, which allows you to specify additional DOFs for RBE3 elements. The “UM” can be used to eliminate some dependency issues inherent to rigid elements in Nastran. For more information, see the Nastran Quick Reference Guide entry for RBE3. The Distance Weighting option in the Update Interpolation Element dialog box, offers the ability to create varied interpolation factors based on distance from the Dependent Node and the specified factor

When you highlight a node in the list, it will highlight in the graphics window, based on the current settings of the Window, Show Entities command. See Section 6.3.2.3, "Window, Show Entities..." for more details. A coefficient of thermal expansion for any Rigid element can either be entered directly into the “Coefficient” field or copied from a defined material using the Material... button in this dialog box. Currently, a CTE on the Rigid element is only supported for NX Nastran, MSC/MD Nastran, and ANSYS (only when using the “2..MPC184 Lagrange Multiplier” formulation). Note: In FEMAP, the use of the CTE for rigid elements is OFF by default in all Nastran Analysis Types. In order for the CTE to be used during an analysis, you must turn on (check) the “Rigid Element Thermal Expansion” option in the “Plate, Beam, and Rigid Options” section of the NASTRAN Bulk Data Options dialog box. This dialog box can be reached by creating an Analysis Set for NX Nastran or MSC Nastran using the Model, Analysis command. See Section 8.7.1.3, "Bulk Data Options" for more information.

4-12

Finite Element Modeling

Convert may be used to convert from a RBE2 to a RBE3 (Interpolation) element and vice versa. If you have rotational degrees of freedom specified for on the RBE2 tab, FEMAP will ask “OK to Convert only Translational Degrees of Freedom?”. Answering Yes will only add TX, TY, and/or TZ (based on the DOFs currently “on”) to the Independent list, while answering No will send all currently selected DOFs to the Independent list. The Single button will bring up a different dialog box which can be useful when creating RBE2 elements between an Independent node and a single Dependent node. All DOF and Thermal Expansion options are available.

RSPLINE When defining Rigid elements for NASTRAN you have a two formulations available. Using the RSPLINE formulation for NASTRAN will display the following dialog box which allows you to pick multiple dependent and independent nodes.

Last term is Independent

Dependent terms

First term is Independent The RSPLINE is defined by selecting the nodes in the order they appear along the interface of the two regions being connected. A term of the RSPLINE is created by first selecting the type of term to be added (Dependent or Independent) then if a dependent term is being created then select the degrees of freedom which you would like to include. A term can be added dynamically to the list by placing the cursor in the Node field then simply picking the appropriate node. Multiple terms of the same type and dof can be defined by first selecting the appropriate options and pressing the “Multiple” button. •

The First and Last term in the list must be independent and FEMAP will present a error until this requirement is satisfied.



Independent terms are graphically shown as a filled in square and dependant terms are shown as open squares.

Other Elements

4-13

Slide Lines Slide elements are used to define contact and sliding conditions between nodes on surfaces. The master and slave nodes are selected by choosing the appropriate button. The Standard Entity Selection box will appear to choose nodes. Once nodes have been chosen, the button for the chosen nodes will contain (on). Otherwise, only the headings Master Nodes... and Slave Nodes... appear. A node may not be chosen as both a master and a slave.

You may select as many master and slave nodes as you need, but the order that you select them defines the order that they will be included into the element. Slide lines should have their master and slave nodes selected in reverse order compared to each other. If you select them in the same order, you will be asked whether you want to automatically reverse the order of the slave selection.

Weld/Fastener This element allows you to specify a weld element (CWELD) or a fastener element (CFAST) for use with NX Nastran and MSC Nastran and is defined using the WELD/FASTENER Element dialog box.

Weld Types There are several different Weld and Fastener Types to choose from: •

Elem to Elem (ELEMID) - Weld is defined from shell element to shell element and a Weld Location must be defined manually using either the Projection or Axis Define methods (see Weld Location Definition Methods later in this section for more information)



Elem to Elem Vertex (ELEMID) - Weld is defined from shell element to a single vertex of another shell element (node on the element) and a Weld Location will be normal to the selected element vertex (node).



Elem Vertex to Elem Vertex (ALIGN) - Weld is defined from a single vertex of a shell element (node on an element) to the single vertex of another shell element and the Weld Location will be between the two selected element vertices (nodes).



Patch to Patch (ELPAT) - Weld is defined in the same manner as Element to Element (from shell element to shell element and a Weld Location must be defined manually using either the Projection or Axis Define methods). The difference is MSC Nastran will determine if the diameter of the weld overlaps onto additional elements, based on the weld’s location, then automatically connect the nodes on those additional elements to the weld.



Prop to Prop (PARTPAT) - Weld is defined from all elements of one shell property to all elements of another shell property and a Weld/Fastener Location must be defined manually, which determines where the weld will intersect the properties

4-14

Finite Element Modeling



Nodes to Nodes (GRIDID) - Weld is defined from a number of nodes (8 Maximum) on shell elements to a number of nodes (8 Maximum) on shell elements and the Weld Location must be defined manually using either the Projection or Axis Define methods



Nodes to Elem Vertex (GRIDID) - Weld is defined from a number of nodes (8 Maximum) on shell elements to a node on shell element and the Weld Location will be normal to the selected element vertex (node).

Note: Take care when selecting the nodes when using Weld Types “5..Nodes to Nodes” and “6..Nodes to Elem Vertex”. The nodes must be chosen as you would choose nodes when creating a shell element (i.e. clockwise or counter-clockwise from the first node to the 3rd or 4th node). If you are using 6 (triangle) or 8 nodes (quad) to define your “patch”, you must first select the 3 or 4 corner nodes then select the “mid-side” nodes starting with the node between the first selected corner node and the second selected corner node and so on. Not ordering the nodes properly will likely cause an error in NX Nastran. •

Elem to Elem (CFAST, ELEM) - Fastener is defined from shell element to shell element and a Weld/Fastener Location must be defined manually using either the Projection or Axis Define methods.



Prop to Prop (CFAST, PROP) - Fastener is defined from all elements of one shell property to all elements of another shell property and a Weld/Fastener Location must be defined manually, which determines where the fastener will intersect the properties. Weld Location Methods

Using the Projection Method

Using the Axis Method

Weld/Fastener Location Definition Methods

A Weld/Fastener Location must be defined manually for Elem to Elem, Patch to Patch, Prop to Prop, and Nodes to Nodes. There are two different Weld/Fastener location Definition Methods to choose from: •

Projection - Weld/Fastener Location is defined by a single node and sometimes a defined vector direction. The vector from the node along the vector direction must pass through both element or nodal patches in order for the weld to function properly.



Axis - Weld/Fastener Location is defined using 2 nodes to represent the positions and direction. Both nodes must fall within the boundaries of the element or nodal patches for the weld to function properly.

Model, Material

4-15

4.2.3 Model, Material FEMAP supports eight types of materials: •Isotropic (See Section 4.2.3.1, "Isotropic Materials...") •2-D and 3-D Orthotropic (See Section 4.2.3.2, "Orthotropic Material Formulation" •2-D and 3-D Anisotropic (See Section 4.2.3.3, "2D and 3D Anisotropic Materials...") •Hyperelastic - Mooney-Rivlin/Polynomial form (See Section 4.2.3.4, "Hyperelastic Materials...") •Fluid (See Section 4.2.3.5, "Fluid Materials...") •Other Types (See Section 4.2.3.6, "Other Types...") These material formulations allow you to simulate different material characteristics. FEMAP allows any element/property type to reference any of the available material types. However, if you plan to use any type but Isotropic, see Section 8, "Analysis Program Interfaces" in the FEMAP User Guide. This topic describes how each type is translated to your analysis program. In general, the 2D material types should only be used by plane (and axisymmetric) elements and the 3D formulations should only be used by solid elements. For some analysis programs, however, the 3D formulations are used to add transverse properties to plate elements. If you do reference a material type that is not supported by the translator, FEMAP will convert it to a supported type (after giving you a warning) but the converted type might not correctly represent the material characteristics that you intended.

Common Features of All Material Dialog Boxes. Even though the material definition dialog boxes are quite different from each other, there are numerous features that appear in all of them. Near the top of each box you will see controls which allow you to define the ID, Title, Color and Layer for the material. The ID will automatically increment after each material you create. The ID can not match the ID of any other existing material. You should always specify a meaningful title (up to 79 characters) because it will help you to identify the material later in drop-down lists throughout FEMAP. The Type button is also found near the top of dialog box and lets you choose the material type that you want to create. There is also a Function “icon button” at the bottom of the dialog which can be used to conveniently create a new Function.

Copying Materials If you need to create a material that is similar to another in your model, you do not have to enter all of the material values manually. Pressing the Copy button will display a list of all existing materials. When you choose a material from the list, the material values will be copied from that material and displayed in the current material creation dialog box. You can then modify those values in any way you want, or even change your mind and copy a different material, before pressing OK to create the new material. If you copy a material of one type into a material of a different type, FEMAP automatically converts the material to the new type. The material constants are converted to a form which represents the material which you copied. For example, copying an isotropic material to a 3D orthotropic material will result in stiffness values which are identical in all three directions, that is isotropic. If you copy the other direction, 3D orthotropic to isotropic, there is no way to represent the orthotropic nature of the material and that information will be lost. You should review carefully any materials which you copy between different types.

Working with Material Libraries Material libraries allow you to create standard materials that you can use over and over again in many different models. When you press Save, the current material is added to the material library file. Pressing Load will display a list of the materials in the library and let you choose one to be loaded into the material creation dialog box. Just like Copy, you can then modify the values before pressing OK to create the material. Also, just like Copy, when you load a material of a different type it is automatically converted. The material ID, Color, Layer and Coordinate System are not saved in the library, nor updated when a material is loaded from the library. For more information on libraries, see Section 2.6.2.8, "Library/Startup" and Section 4.3.6, "Library Selection" of the FEMAP User’s Guide.

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Finite Element Modeling

4.2.3.1 Isotropic Materials... ... are the simplest and most widely used material type. They can be used for any element type. Materials of this type exhibit constant properties in all directions. Therefore all properties (stiffness, thermal, stress limits...) are specified with a single value, which is directionless.

Properties that are not required for your analysis may be left blank (or 0.) For example, there is no need to specify any of the thermal properties if you do not plan to do a thermal analysis. Typically, you can always leave one of the three stiffness parameters (E, G, nu) blank also. FEMAP will maintain its value as zero, but most analysis programs recognize this situation and automatically calculate the third parameter from an isotropic formulation: E G = --------------------------2 × (1 + υ)

4.2.3.2 Orthotropic Material Formulation Care must be taken when specifying structural properties for orthotropic materials. Various analysis programs use different conventions regarding how they refer to the properties, and which properties they require. FEMAP uses the following stress-strain relationship:

Orthotropic Material Formulation

ν 21 – ν 31 1- –-------------- ----------- 0 E1 E2 E3           

– ν 12 1 – ν 32 ----------- ------ ----------ε1  E1 E2 E3  ε2  – ν 13 – ν 23 1  ----------- ----------- -----ε3  E1 E2 E3  = γ 12   0 0 0 γ 23   γ 13  0 0 0 0

0

0

0 0 1 --------G 12 0 0

0

4-17

0

0     0 0    0 0    1 --------- 0  G 23 0

σ1   σ2   σ3   σ 12   σ 23   σ 13 

1 0 --------G 13

...where the bold constants in the shaded area are the ones that you enter. During translation, these terms are converted to the other ones, if required by the analysis program.

2D and 3D Orthotropic Materials... ... define different, in-plane, material characteristics in 2 or 3 primary directions, respectively. These materials are typically used by planar or axisymmetric elements.

The Limit Stress/Strain section allows you to specify limits for tension and compression as well as a shear limit value. Either Stress Limits or Strain Limits may be input (for 2-D only). These values are typically used in conjunction with the laminate property for failure calculations. When exporting solid elements which use a 3-D orthotropic material for NX Nastran, FEMAP will create MAT11 and MATT11 (if needed) bulk data entries. For the same combination in NEi Nastran, FEMAP will create MAT12 and MATT12 (if needed) bulk data entries.

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Finite Element Modeling

4.2.3.3 2D and 3D Anisotropic Materials... ...are a more general form of the 2-D and 3-D orthotropic materials. In this case, material parameters are specified as a general 3 x 3 matrix (2-D), or 6 x 6 (3-D) matrix.

4.2.3.4 Hyperelastic Materials... ...define properties for materials subject to large displacement, both translational and rotational, such as rubber.

Fluid Materials...

4-19

You can input both the Distortional and Volumetric Deformation Constants and the Strain Energy Polynomial Order, or input stress/strain test data in the Experimental Data Functions area to allow the analysis program to calculate these constants. These data functions must be defined as vs. stress type FEMAP functions with stress as the X value and strain as the dependent Y value. Note: Many solvers do not support hyperelastic materials and those that do have restrictions. Please investigate the applicability/rules of hyperelastic materials in the analysis program that they plan to utilize. Note: When using the Experimental Data Functions with Nastran, a Type: “13..Stress vs. Strain” function should be used with X = “Stretch Ratio” values, not Strain and Y = Stress values. In general, “Stretch Ratio” values = Strain values + 1.0. Note: When entering the hyperelastic material constants, Di, be careful. They are translated directly for Nastran and ANSYS, but for ABAQUS the values written are 1 / Di.

4.2.3.5 Fluid Materials... ... defines material properties for fluids, including liquids and gases. This material type is not normally used in a structural analysis, but is used in heat transfer and flow analyses.

The properties on the fluid material type are similar to the heat transfer properties on other material types, however additional fluid specific properties are also available.

4.2.3.6 Other Types... ... defines material properties that do not fall directly under the previous categories. These materials are unique in that the dialog box wording can be modified. When you select this option, you will see the above dialog box. The inputs to the dialog box will change based upon the material type that you choose. The values are then stored with that material type in the FEMAP database. The actual dialog box contents are read from a library file which contains the appropriate information for each material, including type of input, storage area, limits (if any), and dialog box text. This library file can be set in File, Preferences, Libraries. A default library file with the supported materials is shipped with FEMAP.

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Finite Element Modeling

Input can include real numbers, integers, and functions. They may also have input limits associated with them. Function values are designated by the 0..None value when first entering a new material. You will need to input an existing function ID for these fields (or leave it at None). Simply press Ctrl+F to see a list of available functions when in the field.

The hyperelastic materials for NX Nastran Advanced Nonlinear Analysis (SOL 601 & 701) can be specified using this material type. The hyperelastic materials supported for SOL 601/701 are the Mooney-Rivlin, Hyperfoam, Ogden, Arruda-Boyce, and Sussman-Bathe. Each material has a distinct set of parameters which can be entered and these materials are then written to the MATHE entry for NX Nastran. Support for the Mullins Effect (writes MATHEM) and Viscoelastic effect (writes MATHEV) is also available for all SOL 601/701 hyperelastic materials. A non-hyperelastic material with viscoelastic effect (writes MATVE) can be specified using Material Type “NX Nastran Viscoelastic (Sol 601)”. This dialog box is also used to specify the “Gasket Material” (MATG) for NX Nastran Advanced Nonlinear Analysis (SOL 601 only). The MATG can only be used with 6-Noded (Wedge) and/or 8-noded (Hex) Solid elements. There should only be one layer of elements in the direction of gasket thickness. This material requires a “loading curve” and at least one “unloading curve” (up to 10 can be specified) to properly define the “Pressure-Closure Relationship” for the gasket (“Closure” is defined as the “change in gasket thickness”/ “original gasket thickness”). These “curves” should be defined using “functions” in FEMAP. Note: The “Membrane Material ID”, “Yield Pressure”, “Tensile Modulus”, and “Transverse Shear Modulus” MUST be defined for NX Nastran to be able to process the material. Also, the “Yield Pressure” MUST match a point on the “loading curve”. Note: In order to review “Gasket Results” in FEMAP, you must request results in the .op2 file from NX Nastran. To do this in FEMAP, you must set your Results Destination to “2..PostProcess Only” or “3..Print and PostProcess” in the Nastran Output Results dialog box of the FEMAP Analysis Set Manager. (See Section 8.7.1.8, "Output Requests" for more information on Nastran Results) A “Fluid Material” can be created for use with Solid Elements only to represent a fluid volume in Nastran (MAT10). The Bulk Modulus must equal the Speed of Sound (squared) multiplied by the Mass Density. A “Shape-Memory Alloy” (for example, nitinol) can be defined for use in SOL 601. Material properties should be entered for both the austentite phase and martensite phase in order for this type of material to behave correctly. This type of material cannot be used with beam elements. Use Material Type “NEi Nastran NITINOL” to create a shapememory material for use with NEi Nastran.

Function Dependent Materials

4-21

An “Equivalent Laminate Material”, which writes multiple MAT2 entries with IDs higher than 99,999,999, can be created for Nastran. When exported, the material ID in FEMAP will have 100,000,000 added to it for “Membrane”, 200,000,000 for “Bending”, 300,000,000 for “Transverse Shear”, and 400,000,000 for “Membrane-Bending Coupling”. Typically, these materials created by a Nastran run and are only used on planar elements. This material type is also often used to define LS-DYNA materials instead of using the isotropic, orthotropic, and anisotropic defaults, but FEMAP also supports special Hyperelastic materials for MSC/MD Nastran, ABAQUS and MARC. The default library file shipped with FEMAP contains these material types. If you are only using NX Nastran, MSC/MD Nastran, ABAQUS or MARC materials, you can edit the library file to remove other materials for easy reference, but do not to modify any numbers of materials you want to use. You can modify the text in quotes, but all other data must remain the same. You can also create your own materials by adding to the current list. FEMAP will store the information in the appropriate data fields. For information on how to create your own materials, refer to the MS Word file, neutral.doc, installed with the FEMAP executable. Creating materials in this manner, however, is only useful for programs that access FEMAP through a neutral file since our dedicated translators will not recognize them. Next and Prev FEMAP supports over 200 inputs on the material card, but only 24 at a time can be displayed in the dialog box. When you press Next or Prev, the dialog box will scroll to show the other entities that can be input for the specific material model

4.2.3.7 Function Dependent Materials You will notice that many of the material dialog boxes have a tab marked Function References. This tab allows you to assign function references to the various material properties.

The Function References tab contains all of the same properties as the General tab of the particular material type. Instead of entering a material constant, here you may select from a list of already defined functions from a dropdown list. You do not have to choose a function for each property, however, any items that you leave blank will simply be considered as a constant value (not varying with any function).

4-22

Finite Element Modeling

Although they are not shown here, the Function References tabs for the other material types also contain the same fields found on the General tab of each material type. A new function can be conveniently created while defining a material using the Function “icon button” located in the lower left hand corner of the Define Material dialog box. This is the same as using the Model, Function command, except that the Define Material dialog box is still visible and the resulting function ID will automatically be entered into the list. Hint:

All functions that you select for a material must be of the same type. For example, you can not choose a time function for one value and a temperature function for another.

Note: The preferred method for creating functionally dependent materials (especially temperature dependent materials) is to enter the actual desired material values into the function itself, then use the corresponding field on the General tab of the material as a scalar, which many times should be “1”. See Nastran Translation Note 28 in Section 7.1.3, "NASTRAN Translation Notes" for more information regarding certain types of analysis.

4.2.3.8 Nonlinear Materials All materials but Hyperelastic, Fluid, and Other Types have a Nonlinear tab. This allows you to add material constants which are normally required for nonlinear analysis. To begin, you must select the type of nonlinearity that you are trying to model.

Nonlinear elastic and plastic materials are defined by a stress-strain curve, which is defined by a vs. stress function and selected in the Function Dependence property. The function for nonlinear elastic materials should be defined in the first and third quadrants to accommodate different uniaxial tension and compression properties. Nonlinear elastic properties can only be defined for isotropic materials. Nonlinear elastic materials can be made temperature dependent by referencing a “5..function vs. temp” function instead of a vs. stress function, where the Y value is the ID of the Stress vs Strain curve and the X value is the corresponding temperature at which that curve is valid. Elasto-plastic materials use the linear constants coupled with the plasticity modulus, H. This is the work hardening slope, and is related to the tangential modulus, ET(the slope of stress vs. plastic strain) by the following:

Nonlinear Materials

4-23

H = ET ⁄ ( 1 – ET ⁄ E )

If you have already defined Young’s Modulus (E), you may press Compute from Tangent Modulus. By selecting this feature, you can simply input the tangential modulus, ET, and FEMAP will use E to calculate the plasticity modulus, H. The Yield Criterion option contains information on the yield types to be used. This box is only relevant for elastoplastic and plastic nonlinearity types. Four yield criterion are available (von Mises, Tresca, Mohr-Coulomb, and Drucker-Prager). Von Mises and Tresca require input of the initial yield stress, while Mohr-Coulomb and DruckerPrager require input of 2*cohesion and angle of internal friction.

Nonlinear Materials - Extended Material Model The Extended Material Model button enables you to define further information for the nonlinear material model. This is currently only available for the von Mises and Drucker-Prager yield criterion. Von Mises When you select Extended Material Model, and Von Mises is specified, the following dialog box will appear.

Note: The “Initial Yield Stress” in the Define Nonlinear Material dialog box must be set to “1.0” for this to work properly when using this to define temperature dependent materials with a “5..Function vs. Temp” function. Drucker-Prager When you select Extended Material Model, and Drucker-Prager is specified, the following dialog box will appear. You can input both the dilitancy angle and stress ratio for the Drucker-Prager model and specify the type of stress-strain data that you are providing in the Nonlinear Function Dependence. Furthermore, you can provide the initial yield stress and can make this yield stress a function of temperature or strain rate. The function dependence must be of a consistent type with the type of function supplied in the Function Dependence under Nonlinear Properties. By proper selection of these functions, you can generate yield and plastic region information as a function of temperature, strain rate, or both. If the yield criterion is von Mises, all the required information can be input in the Nonlinear Properties dialog box except for yield function dependence on temperature and/or strain rate. You may make the yield stress function dependent by selecting the Extended Material Model, and a selection box will appear which will enable you to choose the appropriate function. Note: Support of the extended material model by analysis programs is limited. You should verify that both the FEMAP translator and the code itself supports the extended material model. Function Dependence vs. Stress Function vs. Temperature Function vs. Strain Rate 1. vs. Stress

Yield Function Not Used vs. Temp vs. Strain Rate

Resulting Stress - Strain Curve(s) Single Curve Temperature Dependent Strain Rate Dependent

4-24

Finite Element Modeling

Function Dependence Function vs. Strain Rate 2. Function vs. Temperature

Resulting Stress - Strain Curve(s) Strain Rate and Temperature Dependent

Yield Function vs. Strain Rate TempFunction vs. Strain Rate

4.2.3.9 Defining Creep Material Properties You will note that many of the material types have a Creep tab. This enables you to define properties for creep analysis. Creep properties can be defined even if no other nonlinear/plasticity properties have been defined. Two creep formulations are available: Empirical Model, and Tabular Model. For the Empirical Model, the Threshold Strain, Reference Temp, and Temp Dependent Rate must be defined as well as the Empirical Creep Law and Coefficients. Two classes of empirical creep law are available. They are:

Creep Law Class 1:

c

ε ( σ, t ) = A(σ) [ 1 – e where

– R(σ)t

b

] + K(σ)t

A(σ) → aσ or ae R(σ) → ce





or cσ g

d

K(σ) → e [ sinh ( fσ ) ] or ee Creep Law Class 2:

c



b d

ε (σ, t) = aσ t

The appropriate law and coefficients are defined by their equations in the dialog box. All inappropriate information will be grayed.

Defining Thermo-Optical Material Properties

4-25

The second creep formulation is tabular model which requires only function inputs under the Tabular Creep Law section. You must define FEMAP function types vs. stress for the three coefficients Kp, Cp (primary creep) and Cs (secondary creep) of the uniaxial rheological model. Note: Similar to hyperelastic materials, support of nonlinear and creep material properties by analysis programs is limited. You should verify that both the FEMAP translator for your analysis code and the code itself supports creep material properties.

4.2.3.10 Defining Thermo-Optical Material Properties Isotropic and orthotropic materials have the ability to also specify thermo-optical properties of the material. These properties are used for heat transfer analyses in programs like TMG. They are not used by Nastran, ANSYS, ABAQUS or any of the other structural programs where FEMAP supports heat transfer analyses. All of the fields are function dependent. You should specify the constant value in the field to the left, which is applied as a multiplier to any function you select from the lists. If you do not select a function, the values are simply constants. The “Front Side” and “Reverse Side” for InfraRed and Solar properties refer to planar elements, where the “Front” is the face in the direction of the element normal.

4.2.3.11 Defining Phase Change Material Properties All materials but Fluid and Other Types have a Phase tab. This allows you to add material constants which are normally required for heat transfer and thermal analysis that involve a phase change (i.e. solid-to liquid, liquid-to-gas).

The phase change material model is primarily available for Nastran and ABAQUS. It can also be used for custom programs or programs that access the FEMAP neutral file. Reference enthalpy need not be specified when using ABAQUS.

4-26

Finite Element Modeling

4.2.4 Model, Property... ...creates a new property. Properties are used to define additional analysis information for one or more elements. Most property data is geometric (thicknesses, areas, radii, etc.), but properties also specify mass and inertia and select the materials to be used. The available property types match the available element types. For an element to reference a property, both the property and the element must be the same type. The only exception is that there is no distinction between linear and parabolic properties. In fact both linear and parabolic elements can reference the same property. •

Line Elements Properties (See Section 4.2.4.1, "Line Element Properties")



Plane Element Properties (See Section 4.2.4.2, "Plane Element Properties")



Volume Element Properties (See Section 4.2.4.3, "Volume Element Properties")



Other Element Properties (See Section 4.2.4.4, "Other Element Properties")

Common Features of All Property Dialog Boxes There are many different dialog boxes used for creating the various property types since different values are required for nearly every element type. Near the top of each dialog box however, you will notice a group of controls which are used to set various parameters for the property to be created. The Elem/Property Type button, used to choose a different property type, can be found here also. This button will display the same dialog box as described in the Model, Element command. ID, Color/Palette and Layer: These options set parameters for the property to be created. Every time you create a property, the default ID will be automatically incremented. Title: This option allows you to provide a title of up to 79 characters for the property. You should always specify descriptive titles because they will appear in the drop-down selection lists and will help you identify the property. If you do not specify a title, FEMAP will create a title automatically based on the type of Property created (format is “Property ID”.. “Property Type” property). For example, if you create a Plate Property without a title, FEMAP will simply title it “1..PLATE property”. Material: This drop-down list allows you to choose the material to be referenced by the property. A few property types (mass, stiffness matrix...) do not require a material, but most do. For your reference, all materials which are defined in your model will be shown in the list. For details on how various material types translate to your analysis program, see Section 8, "Analysis Program Interfaces" in the FEMAP User Guide. In general, for plane element/property types you should pick either an isotropic, orthotropic 2D, or anisotropic 2D material. Similarly isotropic, orthotropic 3D or anisotropic 3D materials should be used with solid elements. Some analysis programs however, support 3D orthotropic materials for plate elements to add transverse properties. You can make your choice by typing an ID, choosing from the list, or by graphically selecting an existing element which references the material that you want. If you do not specify a material (leave the option blank or 0), when you press OK, you will be given a chance to automatically create a new material. You can also click the Material “icon button” next to the Material drop-down list to create a new material. This is the same as using the Model, Material command, except that the Define Property dialog box is still visible and the resulting material ID will automatically be entered into the list.

Copying Properties If you need to create a property that is similar to another in your model, you do not have to enter all of the property values manually. Pressing the Copy button will display a list of all existing properties. When you choose a property from the list, the property values will be copied from that material and displayed in the current property creation dialog box. You can then modify any of these values, or even change your mind and copy a different property, before pressing OK to create the new property. Copying is only useful when you copy properties of the same or similar type. When you copy properties of the same type, all values are directly transferred to the new property. If you copy a property of one type into a property of a different type, FEMAP converts the property to the new type, but many of the property constants may be

Line Element Properties

4-27

meaningless. If the property types are similar, like a bar and beam, the similar properties will be copied. If you attempt to copy a plate property to a beam, or vice versa, you will get meaningless constants. You should review carefully any properties which you copy between different types.

Working with Property Libraries Property libraries allow you to create standard properties that you can use over and over again in many different models. When you press Save, the current property is added to the property library file. Pressing Load will display a list of the properties in the library and let you choose one to be loaded into the property creation dialog box. Just like Copy, you can then modify the values before pressing OK to create the property. Also, just like Copy, when you load a property of a different type it is automatically converted. The property ID, Color, Layer and Material are not saved in the library, nor updated when a property is loaded from the library. For more information on libraries, see Section 2.6.2.8, "Library/Startup" and Section 4.3.6, "Library Selection" of the FEMAP User’s Guide.

4.2.4.1 Line Element Properties Rod Element Properties Rod elements require cross-sectional properties - area and the torsional stiffness. Distributed, nonstructural mass (per unit length) can also be specified. The coefficient for torsional stress is used in the calculation for torsional stress as follows: C × Mθ τ = -----------------J

where τ is the torsional stress C is the coefficient of torsional stress, J is the torsional stiffness, and Mθ is the torsional moment.

Tube Element Properties The tube element cross section is circular. It is defined by the outer and inner tube diameters. Distributed, nonstructural mass (per unit length) can also be specified. In addition, for certain analysis programs, you can use the Tube element to model pipe behavior, specifying an internal pressure and whether or not the ends of the element are closed.

Curved Tube Element Properties Curved tube element properties are the same as the tube, with the addition of a bend radius.

Bar Element Properties In addition to the cross sectional area, numerous inertia properties must also be defined for the bar element. These properties are identical to those required for beam properties except that beam elements contain additional inputs. For more information, see "Beam Element Properties"

Beam Element Properties Beam properties are identical to bar properties except that you can specify different properties at each end of the beam, and you can define a neutral axis offset from the shear center. You must turn on the Tapered Beam option if you want to enter different properties at the second end of the beam. If this option is off, the properties at the second end will be equal to the first end. Care must be taken in properly specifying these properties with respect to the element axes. For FEMAP, I1 is the moment of inertia about the elemental Z axis, which will resist bending in the outer fiber in the elemental Y direction. Some people look at this as the moment of inertia in Plane 1, the plane formed by the elemental X and Y axes. For more information on the element directions, see Section 6, "Element Reference" in the FEMAP User Guide

4-28

Finite Element Modeling

The figure will give some examples of cross sections, their orientations and relative inertias. Vectors show the elemental Y axis, which is the orientation direction.

Small I1, Large I2

Large I1, Small I2

Large I1, Small I2

Distributed, nonstructural mass (per unit length) can also be specified. You can specify up to four stress recovery locations in the plane of the element cross section. If you just specify the first location, and leave the remaining ones blank or zero, FEMAP will automatically assign the remaining three locations with positive and negative combinations of the location that you specified. This feature automates stress recovery for the four corners of a rectangular cross section. The neutral axis offsets should be specified in the local beam coordinate system, based upon the orientation node or vector for the particular elements. This offset is only used to offset the neutral axis from the shear center. The offset of the shear center (and neutral axis) from the vector between the two nodes defining the beam is input on the beam Element command, not the beam Property command. Shape - Section Property Generator A graphical cross section property generator is available for this property type (as well as bar and curved beam). FEMAP can automatically compute the cross section properties and stress recovery locations for common or arbitrary shapes. The common shapes include rectangular, trapezoidal, circular, and hexagonal bars and tubes, and structural shapes such as I, C, L, T, Z and “hats”. Required input for these standard shapes is shown in the following figure.

Line Element Properties

Height

Height

Thickness

Width, Top

Height

4-29

Width, Top

Height

Thickness

Width

Width

Rectangular Bar

Rectangular Tube

Width, Bot

Trapezoidal Bar

Width, Bot

Trapezoidal

Radius

Radius

Thickness Radius

Radius

Thickness

Circular Bar

Circular Tube

Width, Top

Thick, Top Thickness Thick, Bot

Height

Width, Top

I-Beam or Wide Flange (W)

Width, Top Thick, Top Thickness

Hexagonal Tube

Width, Top

Height

Thick, Top Height Thickness Thick, Bot

Width, Bot

Hexagonal Bar

Thickness Thick, Bot

Thick, Top Thickness

Width

Width, Bot

Channel (C) Section

Angle (L) Section

Height T Section

Width

Height

Height

Thick, Bot

Width, Bot

Z Section

Thickness

Width, Bot

Hat Section

An arbitrary shape requires creating a surface before entering Model, Property, and then selecting General Section, pushing the Surface button, and selecting the surface. Whether you select a common or arbitrary shape, you can

4-30

Finite Element Modeling

have FEMAP draw the cross section by pressing Draw. An error in the input will prevent drawing of the cross section. This dialog box can also be used to define the stress recovery locations and orientation vector direction. Note: Clicking the “?” icon on the title bar of this dialog box will bring up the cross-section dimension diagrams for reference purposes. FEMAP will bring up the appropriate diagrams based on whether “Standard” or “NASTRAN” are selected at the top right of the Cross-Section Definition dialog box.

Stress Recovery and Reference Point The Stress Recovery section of this dialog box allows the selection of stress recovery locations at standard points on the cross section. By pressing the Forward Arrow button, FEMAP will move the location to the next standard point, while pressing the Back Arrow button will move the location to the previous standard point. Whether you specify stress recovery locations here or not, you still have the option to input values directly in the Define Property - BEAM Element Type (previous) dialog box. The Reference Point is only used when mesh attributes are assigned to a curve (Mesh, Mesh Control, Attributes Along Curve). The reference point provides an easy method to automatically define the shear center/neutral axis offset for beams that are automatically meshed onto a curve. Any of the Stress Recovery or Reference Point locations can be turned on and off using the check boxes. FEMAP will remember the positions of the Stress Recovery and Reference Point locations even if they have been altered from the defaults (version 9.0.1 and above). When a curve is meshed containing mesh attributes, and the offsets method has been set to Location, FEMAP will place the reference point on the line joining the two nodes, and then calculate the offset of the shear center from this point. The result is stored on the element record as the shear center/neutral axis offset.

Line Element Properties

4-31

Note: The offset stored on the element record calculated from the reference point moves both the neutral axis and shear center from the line joining the two nodes of the beam. The offset stored on the property record and calculated when Compute Shear Center offset is checked offsets the Neutral Axis from the Shear Center. The Attributes Along Curve command also has the capability to place the reference point at a distance from the line joining the two nodes of the beam by setting y and z values. For more information, see "Mesh, Mesh Control, Attributes Along Curve". Orientation Direction This section simply allows you to specify the direction of the orientation vector. This is very important since an inappropriate direction of the vector with respect to the beam mesh will result in erroneous results. The Cross Section Definition dialog box provides a visual representation of the required direction of the orientation vector for the beams. Change Shape This option is only available when editing a cross section for which properties have already been calculated. This option must be turned on before any properties can be changed. Once this option is selected, FEMAP will use the cross section generator to calculate new properties when exiting this dialog box via the OK button. If you simply want to edit stress recovery locations or orientation, FEMAP will use stored values to calculate any change in properties instead of creating an entire new set. This can save some time when making these simple changes. If you wish to convert beam sections to have no shape (but retain the property values), you can use the Modify, Update Elements, Shape... command. Compute Shear Center Offset, Compute Warping Constant These options are only available for beam properties. They are not available for bar or curved beam properties since they are not supported by most analysis codes for these types of elements. If Compute Shear Center Offset is on, FEMAP will use its cross section generator to compute the offset of the neutral axis from the shear center and store the result on the property record. This is on by default since this offset can be important with certain cross sections and such programs as Nastran, ABAQUS, and ANSYS provide support for these offsets. If Compute Warping Constant is on, FEMAP will calculate the warping constant for the cross section. This is off by default since warping is often not important in beam analysis and there is limited support among the analysis programs for warping. Section Evaluation This option allows you to choose the method FEMAP will use to calculate the cross-section property values. When “Standard” is selected in the top right corner of the dialog box, there are two methods: Original and Alternate. In many cases, Original is the only option you will ever need. However, there may be times when Original will calculate negative shear area values for certain thin-walled sections. If this is the case, use the Alternate option. There is a third option available when “NASTRAN” is chosen, which is PBEAML/PBARL. This option will calculate the section property values using the same algorithm Nastran uses during the solving process when evaluating PBARL and PBEAML bulk data entries. This option is helpful when using PBEAML or PBARL properties because FEMAP will calculate the exact same values as Nastran will when the model is solved. Poisson’s Ratio, Nu Allows the user to enter a value for Poisson’s ratio to be used with the “Alternate Section Property Calculator”.

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Finite Element Modeling

Special Note about the Alternate Section Property Calculator. Note: The following section contains information about the “Alternate Section Property Calculator”. This portion of the documentation is intended for any user who would like to know how FEMAP is calculating Beam Section Property values and why FEMAP now has two separate methods for performing this calculation. Users who model with thin-walled beams may find the information in this section very useful in creating more accurate finite element models. For more information on the theory used to develop the “Alternate Section Property Calculator”, please consult the references listed at the end of this section. The alternative method is selected by going to File, Preferences..., choosing the Geometry/Model tab and checking Alternate Section Property Calculation. If the alternative method is selected, a poisson’s ratio keyin is available on the Cross Section Definition dialog box. In FEMAP version 9 and above, changes have been made to the Beam Section Property Evaluation. The original algorithm has been found to generate negative shear area values for some thin walled beam sections. For example, “I” beams with the following dimensions have a negative shear area: •

Height >4.023



Width, Top 1.0



Width, Bottom 1.0



Thick, Top 0.1



Thick, Bottom 0.1



Thickness 0.1

Apart from the one negative shear area, all other properties for the above dimensioned “I” beams are correct. Currently no problem can be found with the algorithm and it gives excellent values for all solid sections and low aspect ratio thin-walled sections. To overcome this issue, the original algorithm has been adapted and an alternative algorithm added. The original algorithm is still the default algorithm to ensure compatibility with files from previous versions of FEMAP. The original algorithm assumes an internal poisson’s ratio value of 0.3. Changing the internal value of poisson’s ratio value to zero prevents negative shear areas. However, this would not provide section property values consistent with previous versions of FEMAP. In order to provide the best compatibility and to prevent bad shear area, in FEMAP 9 the algorithm runs with an initial poisson’s ratio of 0.3 and if that results in a negative shear area or a shear area greater than the area, an error is issued and the algorithm is rerun with a poisson’s ratio of zero. While investigating this problem, an alternative and newer method of evaluating shear area was found (1,2). Instead of using deflection curvature to determine shear area via Timoshenko’s equation (3); the new method equates internal to external shear energy. The resulting shear areas are always positive and well behaved, but they do not exactly match classical values (4) when the poisson’s ratio is not zero. For example, consider a high aspect ratio rectangular beam. The original algorithm calculates a shear area in both directions that matches the equation for a rectangular section (4) with a poisson’s ratio of 0.3: 10 ( 1 + ν ) A  ----------------------- where A = Area and ν = Poissons Ratio  12 + 11ν 

The alternative algorithm satisfies the above equation when poisson’s ratio is zero, but unlike the original algorithm, it calculates different shear areas in the two directions when poisson’s ratio is not zero. This does not agree with the classical equation above where aspect ratio in not included. However, applying shear load to a tall, thin beam is likely to be less effected by poisson’s ratio than applying the same load to a wide, shallow beam. It is therefore almost intuitive that the two shear areas for a high aspect ratio rectangle should be different. The choice between original and alternative is subjective. The original method calculates one “bad” shear area for high aspect ratio thin-walled beam sections but matches classical values for solid sections and gets good properties for low aspect ratio thin-walled sections. The alternative method gets good shear area values for all aspect ratios, but does not match classical values for solid sections with non-zero poisson’s ratio.

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Line Element Properties

1) “Analysis and Design of Elastic Beams” By Walter D. Pilkey Published by Wiley 2) “Shear Correction factors in Timoshenko’s beam theory for arbitrary shaped cross-sections” By F. Gruttmann and W. Wagner Computational Mechanics 27 (2001) Springer-Verlag 3) “Elastic Shear Analysis Of General Prismatic Beams” By William E. Mason Jr. and Leonard R. Herrmann Journal of the Engineering Mechanics Division Proceedings of the American Society of Civil Engineers August 1968 4) “Formulas For Natural Frequency And Mode Shape” By Robert D. Blevins Published by Robert E. Krieger Nastran PBEAML (and PBARL) Sections FEMAP also enables you to create Nastran PBEAML (and PBARL) sections. Although FEMAP evaluates the section properties and stress locations for these sections, if the translator writes PBEAML (or PBARL) Nastran cards, these properties are ignored and only the dimensions are written. In this situation, Nastran evaluates the section properties and stress locations and generates replacement PBEAM (or PBAR) cards. Note: The property values evaluated by Nastran can differ from those evaluated be FEMAP. FEMAP uses a general section property evaluation tool. Nastran may be using different assumptions such as thin wall theory. Some values for some sections, especially warping values, differ considerably. You can suppress the writing of PBEAML (and PBARL) cards when writing a Nastran deck using options on the Bulk Data and Bulk Data Options dialogs. If you do this, FEMAP evaluated properties will be written to the PBEAM and PBAR cards. Note: The definition axes for the Nastran sections is different to the standard FEMAP sections. For the standard FEMAP sections, y is to the right and z is up on the dialog box. For the Nastran sections, y is up and z is to the right - this is to be consistent with Nastran documentation. Required input for the Nastran sections is shown in the following figure.

Dim3

Dim2 Dim4

Dim2 Dim1

ROD

Dim1

TUBE

Dim3

Dim6 Dim4 Dim5

Dim1

Dim1

Dim2

L

I

4-34

Finite Element Modeling

Dim1

Dim4

Dim2 Dim3

Dim3 Dim3

Dim2

Dim4

Dim4

Dim1

Dim1

Dim1

BOX

BAR

Dim2

CHAN

Dim3

Dim2

T

Dim3

Dim2/2

Dim1

Dim2

Dim1/2

Dim1/2

Dim4

Dim4 Dim4

Dim3

Dim4

Dim2

Dim2

Dim3 Dim1

CROSS

Dim2

H

Dim4

T1

Dim2

Dim1

Dim1

Dim4

I1

Dim1

Dim4

Dim4

Dim3 Dim3

Dim3

Dim2 Dim3

Dim2 Dim1

CHAN1

Z

Dim2

Dim1

Dim4

T2

Dim3

Dim3

Dim3

Dim3 Dim6

CHAN2

Dim2 Dim4

Dim5

Dim1 Dim5 Dim2 Dim4 Dim1

BOX1

Dim2

HEXA

Dim1

HAT

HAT1

Link Element Properties Link element properties are used to define 5 different types of elements which link one node to another. When set to Structural, specify the stiffness values, in all six degrees of freedom, at each end of the element. The Structural link element is rigid between the ends.

Line Element Properties

4-35

The other options are all used to set up thermal boundary conditions between nodes. There are options for Conduction, Convection, Advection, and Radiation.

Curved Beam Element Properties The curved beam element properties are just like those for the bar element (see previous paragraphs), and similar to the beam property (except neutral axis offsets from the shear center and warping are not supported) except that you must also specify a bend radius. All elements which reference this property will use this constant radius.

Spring/Damper Element Properties The FEMAP spring element is a combined linear spring and damper, which connects either translational (axial) or rotational (torsional) degrees of freedom. There are two Types of Spring/Damper elements, CBUSH (Nastran only) and Other (NASTRAN CROD/CVISC). When the default solver is set to any of the available Nastran solvers, the default is CBUSH, while Other is the default for all other solvers. You can specify both stiffness and damping values for the same elements, however, some analysis programs do not support the damping values. Note: For Nastran solvers, stiffness and damping can only be specified on the same property when Type is set to CBUSH. When Type is set to Other, entering a Stiffness value for Axial or Torsional will create an “equivalent” PROD/CROD property/element combination to represent the appropriate spring stiffness. Entering a Damping value for Axial or Torsional will create a PVISC property. Nastran BUSH Property Values These properties are used to define the options for the Nastran PBUSH property. The PBUSH property allows you to define Stiffness, Damping, and Structural Damping for each individual DOF. Stress/Strain Recovery coefficients in the translational and rotational DOF can also be defined. The Spring/Damp Loc option defines where the Spring/Damper is located along the line between the nodes defining the element. If the option is off FEMAP will write a blank in Nastran to use the default. The Orientation Csys option defines the BUSH element csys for the element referencing this property. If the Orientation Csys option is off, then Nastran will determine the element csys from the orientation defined on the element.

Note: Previous to FEMAP 10.3, an element formulation was required to correctly export CBUSH elements with a PBUSH property. This is no longer required and only setting Type to CBUSH for the Spring/ Damper Property is required to write CBUSH/PBUSH entries to the Nastran input file.

4-36

Finite Element Modeling

Nonlinear/Freq Resp This button allows you to define the frequency dependent or stress dependant properties for the BUSH element.

For a Frequency Response analysis you can define Stiffness vs. Frequency, Force/Velocity vs. Frequency, and Structural Damping vs. Frequency in each DOF. For a Nonlinear analysis, Force vs. Displacement can be defined for each DOF.

DOF Spring Element Properties Unlike the spring element which acts along the line between the elemental end points, the DOF Spring connects two nodal degrees of freedom - independent of their orientation relative to each other. You choose the degrees of freedom via the buttons at the left of the dialog box. Like the spring however, you can specify both stiffness and damping.

In addition, you can add both nonlinear behavior and frequency dependence to the spring by defining and choosing one or more functions. The “Force vs Displacement” function allows you to specify a nonlinear behavior for the spring as it extends. The “Force vs Frequency” and “Damping vs Frequency” functions allow you to control the behavior of the spring in a frequency analysis. A “Force vs. Frequency” function may also be specified for the Damping value.

Plane Element Properties

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Gap Element Properties For gap elements you can specify an initial gap distance, tension, compression and transverse stiffness and friction constants. You should carefully review which of these options are supported by your analysis program before using gap elements.

For zero length gaps (coincident node gaps), you can specify a coordinate system for orientation. Additional Nastran options include limits on Penetration, and Adjustment, as well as an Adaptive option. For ABAQUS, gap properties are also used to define properties of interface elements, and you can specify the interface normal and width/area.

4.2.4.2 Plane Element Properties Shear Element Properties Shear panel properties are limited to element thickness and distributed nonstructural mass. For some analysis programs, you can also specify effectiveness factors which provide for treatment of the effective extensional area of the shear panel. Effectiveness Factors F3 and F4 are for use with NEi Nastran only.

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Membrane, Bending, Plane Strain and Plate Element Properties

These property types are all variations of plate element properties. They all require the thickness property, but the plate type allows you to vary the thickness at each element corner. Be careful, though, these corner thicknesses will be applied to each element that references this property. The stress recovery locations are measured from the neutral axis of the plate toward the top fiber. These are not offsets, they are simply the location where stresses are recovered. By default, these are “off”, which writes a “blank” field to Nastran solvers. A “blank” in Nastran returns the results at +T/2 for “Top” and -T/2 for “Bottom”. NASTRAN Options The Bending Stiffness (12I/T**3) and Transverse Shear Thickness/Element Thickness (Ts/T) properties are used by Nastran to simulate non-isotropic or sandwich material behavior. In addition to these options, FEMAP now supports choosing different materials for the bending, transverse shear, and membrane-bending coupling behavior. By default, the plate will use the material that you select at the top of the dialog box, however, you can disable any of these properties, or select a different material simply by choosing the options in the lists. NEi Nastran Tension Only... This button is used to define options for the NEi/Nastran tension only shell. Specify the Component Direction to define which element stress Component Direction will be used to determine element failure and the appropriate max Compression Allowable. The Shell Type After Reversion dropdown allows you to choose which type of element you are creating, whether it is a Tension Only Shell or a Shear Panel. For the Tension Only Shell, X and Y Compression Factors are used to determine the stiffness when the element fails. For the Shear Panel, Effectiveness Factors F1 through F4 can be defined to specify treatment of the effective extensional area of the shear panel.

Plane Element Properties

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Laminate Element Properties Properties of this type are different than those for any other type of element. In this case, the normal material reference (at the top of the dialog box), is not used. It is unavailable in this dialog box. Rather, you must choose a predescribed Layup for your laminate property.

Laminate Definition Layup A Layup has information containing the material, physical thickness, and orientation angle for each “ply” in the laminate, as well as any “Global Ply” information. If a Layup does not exist in your model, you can create a new Layup by clicking the “Layup” icon button next to the Layup drop down menu. Offset Bottom Surface Specifies a distance from the reference plane to the “bottom” surface of the laminate. If the check box for this option is NOT checked, the default value will be -0.5 * the overall thickness of the specified Layup. If the check box is checked and the value is 0, FEMAP will align the bottom surface of the laminate with the reference plane. Options Symmetric In general, you must list all plys in your laminate in your Layup. If you are using Nastran or ANSYS, and your laminate is symmetric, you can choose the Symmetric option and only enter one half of the layers. Membrane Only (Nastran) This Nastran option on the PCOMP entry simulates a “derived PSHELL entry” with only membrane terms being computed. (MID1 on the “derived PSHELL”). Bending Only (Nastran) This Nastran option on the PCOMP entry simulates a “derived PSHELL entry” with only bending terms being computed. (MID2 on the “derived PSHELL”) Smear (Nastran) This Nastran option on the PCOMP entry ignores the stacking sequence, sets MID1=MID2 on the “derived PSHELL entry”, and the MID3, MID4, Ts/T, and 12I/T**3 terms are all set to zero. Also, when this option is used, your stress and strain output will be returned in “Top and Bottom” shell format instead of “Ply by Ply”. Smear - Core (Nastran) This Nastran option can be used when creating a laminate which has “Face Sheets” and a “Core”. The last ply of the Layup will be used to represent the “Core”. Half the overall thickness of the other plies that make up the “Face Sheets” will be placed above the “Core” and the other half below the “Core”. The stacking sequence of the “Face Sheet” plies is ignored. Also, when this option is used, your stress and strain output will be returned in “Top and Bottom” shell format instead of “Ply by Ply”.

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Laminate Properties and Failure Theory Many programs support the failure theories listed. You must specify the bond shear allowable, along with strength allowables on the materials if you want to use the failure theory calculations. For NEi Nastran, four additional options for Failure Theory are available. STRESS = Maximum Stress theory, LARC02 = NASA LaRC theory, PUCK = Puck PCP Theory, and MCT = Multicontinuum Theory.

Axisymmetric Shell Properties The axisymmetric shell property contains only 1 property value for the thickness.

4.2.4.3 Volume Element Properties Axisymmetric Element Properties Actually, axisymmetric elements do not have any property values. The FEMAP property for these types is simply used to reference the desired material.

Solid Element Properties Unlike the plane elements, which orient their material axes using an angle on each element, solid element properties can reference a coordinate system to align the Material Axes. This difference is due to the fact that solid elements require orientation of all three principal directions. Plane elements always have their Z direction normal to the plane and can therefore be oriented with a single rotation angle. You can also choose to orient solid elements based on the directions defined by the element's corner nodes.

4.2.4.4 Other Element Properties Mass Element Properties FEMAP mass elements support differing mass and inertia properties in three principal directions. Many analysis programs do not support differing X, Y and Z masses. In this case FEMAP just uses the X mass that you defined. As an input convenience, if you leave My and/or Mz blank (or zero) they will be automatically set equal to the Mx value. If you really want almost no mass value in one of these directions, you must set the value to a small nonzero number like 1E-10. FEMAP can also align the principal mass directions to any coordinate system and offset the mass from a node. Check to see if your analysis program supports these options before using them. Use the Effective Diameter field for mass elements that are part of a model to be solved with FEMAP Thermal. The solver will use the implied area of a sphere with the specified diameter to calculate the relevant conductances.

Mass and Stiffness Matrix Element Properties Properties for mass matrix and stiffness matrix elements are input as a symmetric 6x6 matrix. Since mass matrix elements are only connected to one node, this fully defines all six mass degrees of freedom for that node. Stiffness matrix elements connect two nodes, and hence 12 degrees of freedom. The 6x6 stiffness matrix is simply replicated to form a 12x12 matrix in this case. The following form is used (A is the 6x6 matrix you specify): A –A symmetric A

Note: This formulation does not take into account any geometric transformations required to connect noncoincident nodes, so care should be taken when using this element type.

Slide Line Element Properties You must define the interaction property values for the slide line element which include the slide line plane, width of surfaces, and stiffness and frictional conditions. Both symmetrical penetration and unsymmetrical penetration (for the slave nodes only) are available. No material reference is required for slide line element properties.

Weld/Fastener Element Properties Weld/Fastener connector elements are only available for NX Nastran and MSC Nastran. Only isotropic materials (MAT1 entries in NASTRAN) can be used as the material for a weld/fastener element. First choose if you are creating a CWELD or a CFAST property in the Weld Type section.

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CWELD There are a few options to choose in the Define Property - WELD/FASTENER Element Type dialog box when CWELD is used.

Diameter - This value represents the diameter of the weld. The diameter, length, and material are used to calculate the stiffness of the connector in 6 directions. Spot Weld - When this option is on, “SPOT” is written to the TYPE field on the PWELD entry. This causes the actual length of the weld element to be ignored and instead the stiffness is calculated using an effective length (Le). Le = 1/2 (ta + tb), where ta and tb are the thicknesses of the shell elements A and B which are being connected with the weld. Eliminate M-Set DOF - When this option is checked, it writes out “OFF” for the MSET field on the PWELD entry in the Nastran Bulk Data File. With MSET = OFF, the 2x6 constraint equations are built into the stiffness matrix of the CWELD element thereby condensing the 2x6 degrees of freedom of the nodes used to create the weld connection. This option is available for 0..Elem to Elem, 1..Elem to Elem Vertex, 5..Nodes to Nodes, and 6..Nodes to Elem Vertex weld types (ELEMID and GRIDID) only.

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CFAST Options in the Define Property - WELD/FASTENER Element Type dialog box when CFAST is chosen.

Diameter - This value represents the diameter of the virtual fastener, which is used to locate the virtual grids (nodes) on the shell element patch. Mass - Mass of the fastener. Struc Damping - Structural damping of fastener Material CSys - Material Coordinate System in which translational (KTX, KTY, and KTZ) and rotational stiffness (KRX, KRY, and KRZ) are applied. This option is unchecked by default and Nastran uses a predefined method to determine the x, y, and z-axis of the fastener element. Please see Note below Note: When unchecked, the x-axis of the fastener element will be colinear to a vector from the location the fastener intersects “Patch 1” (Element ID or Property ID) to the location the fastener intersects “Patch 2”, which is defined when creating the element. The y-axis will then be perpendicular to the element xaxis and oriented to the closest basic coordinate axis (in case of identical proximity, basic x-axis first, then y, then z will be chosen for orientation). Finally, the z-axis is the cross product of the element xaxis and z-axis. Absolute - When checked, specifies the Material Coordinate System is an “Absolute” Coordinate System. Unchecked specifies the Material Coordinate System is a “Relative” Coordinate System. KTX, KTY, and KTZ - These values represent the translational stiffness of the fastener in the x, y, and z-axis specified for the element. KRX, KRY, and KRZ - These values represent the rotational stiffness of the fastener in the x, y, and z-axis specified for the element.

Plot Only and Rigid Element Properties There are no properties required for these element types, so they are not normally defined. You can however create properties of these types if you want to use them in any of the other generation / meshing commands.

Model, Layup...

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4.2.5 Model, Layup... ...creates a new layup. Layups are used to define the make-up of a laminate property, ply by ply. You can choose a material ID, physical thickness, and orientation angle for each “ply” in the laminate. There is also an optional “Global Ply” which can be defined. The plies can be sorted by attribute (Ply ID, Material, Thickness, Angle, etc.) in the list by clicking the appropriate column header. The total thickness of the entire layup is displayed above the list of individual plies and is updated each time a ply is added to the layup. Also, a graphical representation of the layup can be viewed by clicking the “Layup Viewer” button next to the New Ply button.

Layup Features ID and Title: These options set the ID and Title for the layup to be created. Every time you create a layup, the default ID will be automatically incremented. Title allows you to provide a title of up to 79 characters for each layup. Global Ply ID (optional): This option can be used to save a particular ply of one layup for use in other layups in your model. If a “Global Ply” is set for each and every Ply in a Layup, FEMAP will write out a PCOMPG as the Property for NX or MXC/ND Nastran. Otherwise, FEMAP will write a PCOMP as the Property. See below for additional uses of the “Global Ply” concept in Post-Processing.

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The “Global Ply” concept can also be used for Post Processing purposes by allowing you to choose any ply of any layup to be the same “Global Ply” as any ply of a any other layup. For instance, a model has two layups, Layup 1 has 7 plies and Layup 2 has 9 plies. If you wanted to post process the results of a particular output vector on the “middle ply” of the model, the “middle ply” for Layup 1 would be ply 4, while the “middle ply” for Layup 2 would be ply 5. Once these plies have been designated with the same Global Ply ID, you can use the Laminate Options functionality of View, Select to create a contour/criteria plot using a the results of the “Global Ply”. You can create a new Global Ply by clicking the Global Ply Icon Button next to the drop down list. In the Global Ply Definition dialog box, you may create a new global ply using the New Ply button. In the New Global Ply dialog box, you may enter a Title (up to 79 characters), and optionally choose a Material, and/or enter a Thickness.

Once you have at least one global ply, you may highlight any ply from the list and then use Edit Ply to change the Title, Material, and/or Thickness, Renumber to renumber the selected ply, or Delete to delete the selected ply, Delete All will simply delete all of the global plies in the model, while Show will highlight all of the elements in the graphics window which are currently using the Global Ply. Note: A Global Ply can only be referenced in a Layup one time. If you use a Global Ply more than once in a Layup, the most recently entered instance of the Global Ply will have the Global Ply designation. Material, Thickness and Angle: The Material drop-down list allows you to choose the material to be referenced for each ply. If you want to create a new material, simply click the “Material” Icon Button next to the Material drop-down list. Thickness allows you to enter the physical thickness of each ply. Angle is used to enter the orientation angle of each ply. The angles are specified relative to the material axes which were defined for the element. If you did not specify a material orientation angle, these angles are measured from the first side of the element (the edge from the first to the second node). They are measured from the rotated material axes otherwise. Layup Editor Buttons There are several buttons in the Layup Editor that allow you to perform different functions. Some buttons are available all the time, while other require that certain fields be filled, one row highlighted, or multiple rows highlighted.

Copy to Clipboard

Paste

Model, Layup...

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Each button or group of buttons is explained in greater detail below. New Ply Once you have a Material, Thickness, and Angle specified, click this button to add the ply to the layup. By default, it will add this ply to the Top of the List (Designated in the dialog box above the list of plies with “Top of Layup”). If you have a ply highlighted in the list, the new ply will be added UNDER the highlighted ply (i.e., closer to the “Bottom of Layup”). If you have multiple plies highlighted, this button is not available Layup Viewer button Clicking this button will bring up the Layup Viewer window. For a more detailed description of the Layup Viewer, see Section 4.2.5.1, "Layup Viewer". Update buttons Once a ply has been added the list, the definition of that ply can be updated using the Update Global Ply, Update Material, Update Thickness, or Update Angle buttons. These commands are available when one or more plies are highlighted in the list of plies (except Global Ply, which can only be used for one ply at a time). Once the desired plies are highlighted, enter the new value for Material, Thickness, and/or Angle, then click the appropriate button to update all highlighted plies with the new value. Duplicate Available when one ply or multiple plies are highlighted. Simply highlight the plies you would like duplicated in the list of plies, click the Duplicate button, and the duplicated plies will be added to the top of the list of plies. Delete Available when one ply or multiple plies are highlighted. Simply highlight the plies you would like delete in the list of plies, click the Delete button, and the plies will be deleted from the list of plies Symmetry Available only when multiple plies are highlighted. Simply highlight the plies you would like to “mirror” in the list of plies, click the Symmetry button, and the “mirrored” plies will be added to the top of the list of plies in reverse order as the were originally in the list. Reverse Available only when multiple plies are highlighted. Simply highlight the plies you would like to “reverse” in the list of plies, click the Reverse button, and the order of the selected plies will be reversed in the list based on the original position (i.e., the selected ply which was closest to the “Bottom of Layup” will now be closest to the “Top of Layup” in the list). Move Up and Move Down Available when one ply or multiple plies are highlighted. Simply highlight the plies you would like moved up or down in the list of plies, click the Move Up or Move Down button, and the selected plies will be moved closer to the “Top of Layup” (Move Up) or “Bottom of Layup” (Move Down) one ply at a time. Rotate Available when one ply or multiple plies are highlighted. Simply highlight the plies you would like to rotate (alter angle) in the list of plies, click the Rotate button, and the “Angle” of the selected plies will updated by adding or subtracting the number entered in the Rotate Ply By dialog box. Enter a negative number to subtract from the current angle. Compute Always available once a single ply has been added to the layup. This command will calculate the equivalent mechanical properties for the layup. These values will be sent to the Messages dockable pane. Note: If you have the Entity Info window open while creating or modifying a Layup, the equivalent properties will be calculated “live” every time a ply is added or modified. This is a great way to create a layup which will behave as expected in your model.

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The calculated “equivalent laminate property” values include: •

Total Thickness



In-Plane Properties (2-D orthotropic)

Modulus of elasticity (X and Y directions) Shear Modulus (XY) Poisson’s Ratio Coefficient of thermal expansion (X,Y, and XY) •

Bending/Flexural Properties (2-D orthotropic)

Modulus of elasticity (X and Y bending) Shear Modulus (XY bending) Poisson’s Ratio Coefficient of thermal expansion (X,Y, and XY bending) •

Compliance Matrices - These are provided for advanced users working with composites. The inverse are also provided for your convenience.

A Matrix (extensional stiffness) B Matrix (coupling stiffness) D Matrix (bending stiffness) A-Inv Matrix B-Inv Matrix D-Inv Matrix Copy, Copy to Clipboard, and Paste Copy allows you to copy all plies of an existing Layup in the model by simply selecting a Layup from a selection dialog box. The Copy to Clipboard icon button is only available when one ply or multiple plies are highlighted. Simply highlight any number of plies in the list of plies, click the Copy to Clipboard icon button, then the selected plies will be placed on the clipboard. Clicking the Paste icon button will Paste the plies into the current layup at the top of the list of plies. You can now reposition the plies using the Move Up and Move Down buttons. Note: The “copied” plies will remain on the clipboard until over-written by another copy operation from a windows program. If you desire, you can “copy” from a layup, then open another layup (new or existing) and “paste” those plies into that layup.

Working with Layup Libraries (Save and Load buttons) The layup library allows you to create standard layups that you can use over and over again in many different models. When you press Save, the current layup is added to the Layup library file. Pressing Load will display a list of the layups in the library and let you choose one to be loaded into the layup editor dialog box. You can then modify the values before pressing OK to create the layup. The layup ID is not saved in the library, nor updated when a layup is loaded from the library. For more information on libraries, see Section 2.6.2.8, "Library/Startup" and Section 4.3.6, "Library Selection" of the FEMAP User’s Guide.

4.2.5.1 Layup Viewer The Layup Viewer allows you to graphically visualize the current layup being created or edited. Each ply currently in the layup will be shown and labeled with Ply Number, Thickness, Orientation, and Material in the Layup Viewer. The ply at the top of the viewing area always represents the “top” of the layup. Initially, all of the plies are shown in the viewing area, with all plies being scaled based on the size of the largest ply. In layups with a large number of

Layup Viewer

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plies or plies with large variation of thickness, this can create a somewhat cluttered display. The entire Layup Viewer can be resized and the viewing area scaled and scrolled to allow in-depth examination of specific plies.

General Controls and Options The layup display can be scaled using the Scale slider bar. When the slider is all the way to the left, this represents the default display and the “middle” of the layup will always be returned to the “middle” of the display area. Once the layup has been scaled, you can explore different sections of the layup by moving the scroll bar up and down on the right side of the Layup Viewer. Note: When using the scroll bar, you will notice that the “top line” of the “top ply” and the “bottom line” of the “bottom ply” will stop at the “middle” of the display area. There are several options in the Layup Viewer which enable you to choose how the layup should be displayed. Also, the display can copied to the clipboard then pasted into other windows programs. The options are explained in greater detail below. Thickness Allows you to choose if each ply should be displayed based on a scaled representation of the ply thickness or if each ply should be shown with a Constant thickness. Note: The “constant thickness” is determined by dividing the available display area height by the number of plies (when the layup display is NOT scaled). Ply Angles When this box is Checked, the ply orientation angles will be displayed graphically on each ply. This option is ON by default. Titles When this box is Checked, the Title of the ply material will be displayed instead of only the ply material ID. This option is OFF by default. Display Color • Material Color - Uses the material color assigned to each material. If you have not specified any special material colors, all of your plies will be the same color.

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Random Color - Assigns a random color to each material in the model for Layup Viewer purposes only. If you have not defined material colors, this is an easy way to see differentiation between layers of different properties.



Monochrome - Changes the layup display to Monochrome (Grayscale) which can be useful if copying the layup display to another program for printing purposes.

Copy to Clipboard button Copies the layup display to the clipboard. By default, the Visible Only option is checked, which means only the plies currently in the display area will be copied to the clipboard. When unchecked, the entire layup will be copied to the clipboard. Note: On 32-bit operating systems, if the image of the entire layup becomes larger than 13,500,000 pixels, the Visible Only option will NOT be available to uncheck and can NOT be turned OFF. You will still be able to copy the visible portion of the layup, but not the entire thing at once. In certain cases, another program (such as Microsoft Word) may not be able to paste the image from the clipboard. If this is the case, try scaling the image less. One way to do this and still get a useful image of the layup may be to use the Constant Thickness option. This is not a restriction when running FEMAP on 64-bit operating systems.

Creating Loads And Constraints

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4.3 Creating Loads And Constraints This section describes methods to load and constrain your model. Loads and constraints are applied in a similar manner. Both are input as part of sets. Therefore, you can define multiple load and constraint sets for your analysis. You can apply loads and constraints to geometry and/or FEA entities. You can even copy or combine sets for either loads or constraints. The sections that follow will first explain the application of loads, and then move on to constraints.

4.3.1 Create/Activate Load Set 4.3.1.1 Model, Load, Create/Manage Set...

Ctrl+F2

... displays the Load Set Manager. This menu command is also available on the tray at the bottom right portion of the graphics window, as well as by choosing New from the Loads object context-sensitive menu in the Model Info tree. The Load Set Manager can be used to create new load sets; update the title of an existing load set; renumber, delete, or copy the active load set; as well as define “Nastran LOAD Combination sets” for Nastran. Create new load set Update the title of an existing load set Renumber highlighted Load Set Delete highlighted Load Set Delete all Load Sets Copy highlighted Load Set Define “Nastran LOAD Combination Set” Deactivate All Load Sets

Title Filter

Clear Title Filter

To activate a load set that already exists, simply highlight it from the Available Load Sets... list. When a new load set is created, it will automatically become the “Active” load set. To deactivate all load sets, press None Active. Note: When a “combined” load set is “Active”, no loads will be visible in the FEMAP graphics window, regardless of options set in the Visibility dialog box (View, Visibility) and Model Info tree. Creating New Load Sets To create a new load set, press the New Load Set button.

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The next available load set ID will automatically be entered in the ID field when creating a new load set, but any load set ID not currently being used in the model may be entered. You may also enter a Title. As always, you should choose a descriptive title. The titles are displayed, along with the IDs, in the Available Load Sets - Selected Load Set is Active list of the Load Set Manager. Press OK to create a load set or press More to create a load set, then be prompted to make another. Load Set Type You may choose a Set Type for the new load set. A Standard load set is any combination of Load Definitions, Body Loads, and Other Loads used to define the loading conditions for that load set. A Nastran LOAD Combination is a special type of load set which is a combination of “referenced” Standard load sets in the model. When used, all of the selected Standard load sets referenced by a Nastran LOAD Combination Set are written to the Nastran input file and combined by Nastran via a LOAD entry also written to the input file. Note: Only Forces, Moments, Pressures, loads on Scalar points (SPOINTS), Rotational Velocity Body Loads, and Gravity Loads may be combined using the LOAD entry. Also, Nastran LOAD Combinations in FEMAP are only used when performing a Static Analysis. Once a Nastran LOAD Combination has been created, highlight it from the list in the Load Set Manager and press the Referenced Sets button. The Referenced Load Sets for Nastran LOAD dialog box will appear:

Highlight any number of Standard load sets from the list of Available Sets. Click Add Referenced Set to have them placed in the Referenced Sets list. By default, each load set placed into the Referenced Sets list will be included with a Scale Factor of “1.0”. If desired, the For Referenced Set “Scale Factor” can be changed before pressing the Add Referenced Set button and all highlighted load sets will be placed in the Referenced Sets list using that Scale Factor. These scale factors will be written to the appropriate “Si” fields of the Nastran LOAD entry for each load set. Update Scales Factors will update the scale factors of all sets currently highlighted in the Referenced Sets list, while the Remove Referenced Set button is used to remove highlighted load sets from the Referenced Sets list. Also, an Overall “Scale Factor” may be entered for the entire set, which is written to the “S” field of LOAD entry. Note: A Referenced Load Sets command may be added to any menu or toolbar using the Tools, Toolbars, Customize command. This command is located in the Additional Commands category on the Commands tab of the Customize dialog box..

4.3.2 Load Definitions Every time a load is created on finite element entities (i.e., Model, Load, Nodal; Model, Load, Nodal on Face; and Model, Load, Elemental) or geometry (Model, Load, On Point; Model, Load, On Curve; Model, Load, on Surface) a “Load Definition” will also be created in FEMAP. A Bolt Preload will also create a Load Definition. These Load Definitions will appear in the Loads branch of the Model Info tree and can be given a title. Each Load Definition will contain all of the individual loads which were created at the same time using a Model, Load... command. Load Definitions can then be edited, listed, and deleted and all individual loads contained in that Load Definition will be edited, listed, or deleted.

Load Definitions

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Note: All of the commands for listing, deleting, and modifying individual loads are still available in FEMAP. For example, if you chose to put a Force load of 1 unit on 5 selected nodes, a single “Load Definition” would appear in the Model Info tree. In this case, if the Load Definition were to be edited, 5 individual loads would be modified using one command.

Load Definitions can be removed at any time using the Remove Definition command on the context sensitive menu in the Model Info tree and the individual loads from that Load Definition will be moved under the appropriate heading in the Other Loads branch. The Other Loads branch contains headings for On Geometry, On Mesh, Bolt PreLoad, Nodal Temperatures, and Elemental Temperatures. Also, a Load Definition can be created from any number of loads of the same type (i.e., any number of Nodal Forces, Elemental Pressures, or Displacements on Curves, etc) by highlighting them in the Model Info tree and using the Create Definition command from the context sensitive menu. If you choose loads of various types and then use the Create Definition command, FEMAP will create a Load Definition for each separate type of load that was highlighted. The Auto Create Definition command goes one step further and will create load definitions based on load type, load value, and additional loading parameters (i.e., element face where load applied). For instance, if you choose 10 pressure loads from the list of Other Loads which all have the same values and are all applied to the same element face, this command will create a single load definition. If instead, you choose 10 pressure loads, 5 with one value and 5 with a different value, this command would make two separate load definitions.

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For more information about the Remove Definition and Create Definition commands, along with the process of combining Load Definitions, please see Section 7.2.1, "Tools, Model Info" under “Loads and Constraints in the Model Info Tree”

4.3.3 Finite Element Loads FEMAP allows you to create loads directly on finite element entities. These types of loads will be exported directly to the solver on translation, assuming that the translator supports the type of loading input. Loads can be applied to the entire finite element model (Model, Load, Body command), to individual or groups of nodes (the Model, Load, Nodal, the Model, Load, Nodal, and the Model, Node, Nonlinear Force commands), and to individual or groups of elements (the Model, Load, Element command). Each type of load and its command is discussed in more detail below.

4.3.3.1 Model, Load, Body Body loads act on all elements of your model and represent global motions, accelerations or temperatures. You must activate the body loads that you want prior to defining load values, by checking the various Active boxes. Body loads can be separated into acceleration, velocity, and thermal. A Coordinate System other than “Global” may be specified for all “body loads” in a particular load set. This coordinate system will be written out to the CID field of the GRAV and/or REFORCE entires for Nastran. Time and Frequency Dependence can be specified for Translational and Rotational Accelerations, as well as, Rotational Velocity by selecting an existing FEMAP function from the drop-down list. You can also create a new function by clicking any of the “Function” icon buttons next to the Time/Freq Dependence drop-down list boxes.

Translational Accel/Gravity and Rotational Acceleration These body loads represent translational and/or rotational acceleration. Input must always be in the global directions. Translational accelerations are often used to represent gravity loads. Watch the units however, these are not specified in “g’s”. Rotational Velocity This type of body load represents a rotational velocity and the resulting loads which are caused by centripetal acceleration. Center of Rotations This specifies the location of the center of rotation for the rotational body loads (rotational velocity and rotational acceleration). You can graphically select the Center of Rotations graphically by highlighting one of the fields in this portion of the dialog and then clicking in the graphics window. To select a precise position, you may want to use Snap to Grid, Snap to Point, or Snap to Node mode.

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Thermal The Default Temperature is the temperature of all nodes/elements which are not given a specific temperature in this load set by nodal or elemental temperature loads. This option can be used to quickly assign a temperature for the entire model. Rotating Around Vector... button This utility allows you to specify a “Rotation Vector” (using any vector method in FEMAP) for all “rotational” body loads in a particular load set. Once you select the vector, FEMAP allows you to enter a value for Velocity and Acceleration around this specified vector. Clicking OK will return you to the main Body Loads dialog box and the “transformed” values for the entered Velocity and Acceleration will now appear in the appropriate X, Y, and Z components.

4.3.3.2 Model, Load, Nodal Creating nodal loads is a two step process. First, you must select the nodes where the load will be applied. As always, this is done using the standard entity selection dialog box. After you select the nodes, you will see another dialog box which defines the load. The first selection you should make is the type of load you wish to create. FEMAP supports eleven (11) types of nodal loads for various types of thermal and structural analysis - forces, moments, displacements, enforced rotations, velocities, rotational velocities, accelerations, rotational accelerations, nodal temperatures, nodal heat generation and nodal heat fluxes. The last 10 load types available are Fluid specific and are only accessible through the FEMAP neutral file. As you choose a load type, FEMAP will disable or hide any controls in the load definition dialog box which are not required. After choosing a load type you can proceed to define the other load parameters and values.

Title: Allows you to enter a title for the “Load Definition” being created. If you do not enter a title, a default title will be created based on the type of load which was created.

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For example, if you create a Force on a selected node or nodes, the default title will be “Force on Nodes”. Color/Palette and Layer: These controls define parameters for the load to be created. Coordinate System: This option is only available if you select the Components method for direction for non-thermal load types. The components are defined relative to the selected coordinate system. If you select a cylindrical or spherical system, the true direction of the loads also depends on the location of the node where it is applied. For example, a positive radial force goes in a different direction if the node is at 0 degrees, than if it is at 180 degrees. Direction: All non-thermal load types are vector quantities which require a direction. FEMAP provides five methods to define the direction of a load: Components, Vector, Along Curve, Normal to Plane, and Normal to Surface. The Components method simply requires input of components in the three directions. For all methods except Components, you must check the Specify button to either define the vector (FEMAP standard vector definition dialog box will appear), select the curve, define the plane (FEMAP standard plane definition dialog box will appear), or select the surface. These methods provide great flexibility for defining the direction of the loads. Note: Since these loads are created on the nodes themselves, the actual method of computing the direction is not stored. FEMAP calculates the direction from the method, and then stores the result in component form. This enables you to modify or remove any geometry that was created to specify the direction without changing the load direction. If you attempt to edit or list the load, the values listed will be in component form. Only loads attached directly to geometry store any information regarding the direction method.

Hint:

When choosing the Along Curve or Normal to Surface options, be careful that the nodes fall within the length of the curve or the area bounded by the surface. If the curve is anything but a line, FEMAP will attempt to project the position of the nodes onto the curve to determine the direction of the curve at that location. A similar projection is also required for the Normal to Surface method. If the projection falls well outside the curve or surface actual bounds, unexpected values for the direction may result.

Choosing a Load Creation Method There are three methods available to create loads on the nodes that you selected. The simplest, and default method, is to assign a constant load value to each of the nodes. As an alternative, you can define an equation which defines the value at each node. If you choose this method, you must select a variable (default is i - must select Advanced under Variable to change it) which will be updated to contain the ID of the node where loads are being defined. Then, instead of entering a numeric value for the loads, enter an equation in Value which uses the variable. You will find the XND(), YND() and ZND() functions very useful in defining loads in terms of the locations of the nodes that you are loading. Note: The XND(), YND(), and ZND() functions will use a load’s definition coordinate system. For example, in a cylindrical coordinate system, XND() would be the radial coordinate of the node, YND() would be theta coordinate of the node, and ZND() would be the coordinate in the Z-axis of the node. If instead of entering an equation, you enter a numeric value, that value will be assigned to every node, just as if you had specified a constant. Conversely, if you enter an equation, but also set Constant, the equation will be evaluated prior to load definition and the constant result will be assigned to all selected nodes. For example, if you choose to enter an equation in Value such as: 10*(xnd(!i)-xnd(1))+50

each node will receive a load which is equal to fifty, plus ten times the length in the X direction between that node and node 1. Note: The equation is evaluated at each node, and the actual calculated value of the load is stored as a nodal load. The equation, itself is not stored. Equations are only stored for geometric loads.

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A third method is available in FEMAP 9.3 and above, and this method is to use a “Data Surface”. There are several different types of Data Surfaces which can be created and in most cases, a Data Surface allows you to vary a value based on specific parameters of an entity (i.e., XYZ coordinates; Node or Element ID; spatial locations - 1-D, 2-D, or 3-D; mapped results from different mesh; parametric locations on geometry). These Data Surfaces can be created prior to load creation using the Data Surface Editor (For more information on the Data Surface Editor, see Section 7.2.5, "Tools, Data Surface Editor"). You can also click the “Data Surface” Icon button in the Create Loads dialog box and choose from the list of available Data Surfaces to create a new one.

Time, Temperature or Frequency Dependent Loads If the loads that you are creating are constant, simply set this option to 0..None. However, if your loads vary with either time, temperature or frequency, you can choose the appropriate function to define that dependence. Prior to creating your loads, you must use the Model, Function command to create the functions, so that they can be selected from the list. The Y values of the function are used to multiply the constant values that you specify in this dialog box. Do not confuse frequency dependence of the load value (specified here) with frequency dependence of the phase (specified at the bottom of the dialog box for frequency analyses).

Creating Component Loads (Forces, Moments, etc.) For component of non-thermal loads (forces, moments, displacements, enforced displacements, velocities, rotational velocities, accelerations, and rotational accelerations) you must activate the various load components, using the option boxes, prior to setting the load value. There is no load applied to any component which is not activated. For forces, moments, velocities, rotational velocities, accelerations, and rotational accelerations, this is equivalent to activating the component and then applying a zero (or blank) load. For displacements and enforced rotations, however, these two alternatives are not equivalent. With the component deactivated, that component is free to move (displace) freely. Activating the component and then specifying a zero displacement (or a blank), prevents all movement of that component. This is similar to a constraint. As just described, FEMAP will allow you to activate load components which have a zero (or blank) load value. You may not however, have all load values equal to zero. If you want to use displacement loads as pseudo-constraints, you must specify at least one small nonzero value, like 1E-10 or smaller. You should never have to create a zero force or acceleration, since it will have no effect. Phase: Non-thermal loads also allow you to specify a phase. This value is only used for frequency analyses. In addition, for frequency response analyses, you can make the phase frequency dependent by selecting an additional function.

4.3.3.3 Model, Load, Nodal On Face... ... is the same as Model, Load, Nodal, except that instead of directly selecting the nodes where the loads will be applied, here you select the faces of elements. You will first use the standard entity selection dialog box to select the elements which reference the nodes where you want to place loads. Then, the face selection dialog box (as described later in Model, Load, Elemental) is used to limit the nodal selection to specific element faces. When you have selected the element faces, FEMAP will automatically determine the nodes where loads will be defined, and this command will continue, just like the normal Model, Load, Nodal command. Note: This command can be a convenient method of specifying nodal loads on complex models, especially on solid models where you can use the adjacent faces approach (see Section 4.3.3.2, "Model, Load, Nodal"). This is an alternative to creating geometric loads and can be very useful to create loads on a portion of a surface.

4.3.3.4 Model, Load, Elemental... ...is used to create elemental loads. The process is very similar to Model, Load, Nodal. You must first select the elements where the load will be applied using the standard entity selection dialog box. Then, another dialog box allows you to define the load type and values similar to the Create Loads on Nodes dialog box. The one major difference is that you will not be able to specify a direction. All elemental loads have a certain prescribed direction (typically normal to face of application). There are seven types of elemental loads in FEMAP: distributed loads on line elements, pressure, temperature, and four types of heat transfer loads - heat generation, heat flux, convection and radiation. Again, just like nodal loads,

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you should select the load type first. This choice will disable or hide all controls which are not necessary for the type of load you are defining. Finally, specify the other load parameters and values. You can also make elemental loads function dependent, just like nodal loads, as well as input a constant or variable load. You will find the XEL( ), YEL( ), ZEL( ), XEF( ), YEF( ) and ZEF( ) functions very useful in defining loads in terms of the locations of the elements and element faces that you are loading. If instead of entering an equation, you enter a numeric value, that value will be assigned to every element, just as if you had specified a constant. Conversely, if you enter an equation, but also set Constant, the equation will be evaluated prior to load definition and the constant result will be assigned to all selected elements.

Creating Distributed Loads Distributed loads are forces applied along the length of line elements (bars, beams...). Their load values are specified as a force per unit length. You can specify a different value at each end of the element. If you want a constant load along the length, you must specify the same End A and End B values. If you leave End B blank, zero load will be applied at that end. In this case the same function dependence will apply to the loads at both ends of the element. Distributed Load Direction After you specify the load magnitude and phase, press OK. You will be prompted for the load direction, which can be along any of the elemental or global axes. You can not specify an arbitrary direction or the axis of any other coordinate system. The elemental axes are determined by the element orientation. For elements that do not require an orientation (rods, axisymmetric shells...) you should always use the global directions.

Creating Pressure Loads Elemental pressure loads always act normal to an element face or edge. For this reason, you can only apply pressure to plane or solid elements. You may not apply pressure to line, or other element types. Just like distributed loads, you first define the load magnitude and phase, then any function dependence. You have the option to input the pressure at corners. This will require input of four values and enables you to specify a varying pressure load across an element. This capability is most useful when defining a variable pressure load across a surface. Note:

Not all analysis programs support pressures at the corners of elements. If you translate to a program that does not support corner pressures, FEMAP will automatically average the corner pressures and output a centroidal value. You also have the option to specify the direction of the pressure. When this option is selected FEMAP will prompt you for the direction of the pressure using coordinates or a vector. Specifying a direction for pressures is only supported for Nastran. If pressures are defined in this manner for other solvers FEMAP will simply create pressures normal to the selected element face. . . .

Specifying Face IDs For pressures, when you press OK, you will be presented with the following dialog box to choose the face or faces where the pressure will be applied:

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This provides four ways to select the faces. The most obvious is to simply choose Face ID and select the ID of a face. For details on how face numbers for plane and solid elements are defined, see Section 6, "Element Reference" in the FEMAP User Guide. Alternatively, you can simply choose the face graphically by moving the cursor near the center of the face and clicking the left mouse button. The selected face will be highlighted. If you chose an unexpected face, simply move the mouse and click again until you get the face you want. Also, you have the option to select the “Front Face” or the “Back Face” when choosing the face of a plate element. This is strictly a way to choose a particular face without having to rotate the model. While this method is easy to understand, it has the disadvantage of applying the loads to the same face number on all selected elements. If the elements where you need to apply loads are oriented randomly, this method is not very effective. You will either need to use one of the other methods, or in some cases you can reorient the elements (see Section 4.8.3.12, "Modify, Update Elements, Reverse/Orient First Edge..." F5 3

Element Normal

4

F2

F4

F1

F6

1

F3

2

Triangular elements do not have a face 6.

In most cases, loads on plane elements will be applied to face 1. In this case positive pressure acts in the same direction as the face normal (as determined by the right-hand rule). Conversely, if loads are applied to face 2, their positive direction will be opposite to the face normal. Therefore a positive pressure on face 2 is equivalent to a negative pressure on face 1. If you need to apply edge loads, they can be applied to faces 3 through 6 as shown. Their positive direction is inward, toward the element center.

Choosing Faces Near a Surface If you have used geometry to define your elements, or if you just have surfaces in your model, you can apply loads to element faces which are close to a selected surface. When you choose Near Surface, you must also choose a surface and specify a tolerance. Loads will be applied to the faces of the selected elements that are closer than your specified tolerance from the surface. This method can only be used to apply pressure to Face 1 of planar elements (not to the edges). Choosing Faces Near a Plane The Near Coordinates method is very similar to Near Surface. Instead of specifying a surface, however, you choose a coordinate system, direction and position. This defines a planar surface, which is used along with the tolerance to find the closest faces. Choosing Adjacent Faces The final and most powerful method for choosing faces, especially for complex solid and planar element models, is Adjacent Faces. You choose just one initial face (and the associated element ID). This can be done very easily by graphically selecting the face. You then specify a tolerance angle. FEMAP will search all selected elements for faces that are connected to the face that you chose and that are within the specified tolerance from being coplanar (colinear for planar elements) with an already selected face. This can be used to find all faces on an outer surface (or edge) of a solid (or planar) - regardless of the shape. By selecting the option Matching Normals Only you can further limit the faces selected by allowing only elements with matching normals to be selected.

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Selected Face Loads on Adjacent Faces

In the picture above, loads could have been applied to all exterior faces, including those inside the hole, by choosing a tolerance greater than 90 degrees. Loads could have been applied just in the hole by selecting a face inside the hole and specifying a fairly low tolerance. As with Face ID, you have the option to select the “Front Face” or the “Back Face” when choosing the face of a plate element. This is strictly a way to choose a particular face without having to rotate the model. Choosing Faces Model Free Faces The Model Free Faces method simply applies the load to every “free element face” in your model. For more information about determining “Free Faces” see Section 7.6.4, "Free Face". Pressures on Axisymmetric shells Axisymmetric shell elements only have a top and bottom surface. With the top defined as the positive normal direction from node 1 to 2. You have the choice of loading either the top or bottom surface. NOTE: Since these elements do not have a orientation the direction of the pressure is not known. or viewing purposes use the Axisymmetric Axis view option to set the orientation required by the analysis package.

Creating Elemental Temperatures For temperature loads, you can specify a single Temperature value. This value is assigned to all selected elements. You may also specify a Gradient value which will be also simply be assigned to the element and will vary the temperature by this amount between the top and bottom face of the element. No face specification is required for temperatures, they apply to the entire element.

Creating Loads for Heat Transfer All of the loads for heat transfer analysis are created similarly to pressure and temperature loads, the only difference is the parameters that need to be specified. Heat Generation For heat generation, only a single constant is required - the generation rate. Heat Flux Elemental heat flux is applied normal to an element face. You must specify the rate of flux, and, just like pressure, apply the flux to a specific face. Alternatively, you can define a directional heat flux. In this case, you must also specify a surface absorptivity and temperature for the selected face. And, after pressing OK, you must specify a flux direction. The direction is defined either as a constant by giving the components of a vector in the direction of the flux, or as a time varying vector, by choosing three functions which contain the components defined as a function of time. In either case the components must be specified in global rectangular coordinates.

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Finally, after defining the direction, you will choose the face(s) where the fluxes will be applied. For more information about choosing faces, see "Creating Pressure Loads". Convection Free convection loads require the convection coefficient and the film temperature, along with the face where the convection is acting. As always, the face is chosen after you press OK, in the standard fashion. For more information about choosing faces, see "Creating Pressure Loads". Forced convection loading is also supported, although only for a 1-D type analogy. In this case you must specify the flow rate and diameter along with the temperature, so the proper coefficients can be calculated. For this type of analysis, you will also have to specify numerous fluid properties in the Model, Loads, Body command described earlier. Special Case - Forced Convection Over a Plate or Surface For Nastran, forced convection loads can also be used to model one or more flows over a plate. This is a very specialized capability and requires a thorough understanding of Nastran’s thermal capability before you attempt to perform this type of analysis. To model this condition you must follow these steps: 1. Model the plate. You can use any general mesh, however a rectangular mapped mesh will be much easier to understand, and will more accurately represent the flow. 2. Model “flow tubes”. Since Nastran only has forced convection along “line elements”, i.e. a 1-D case, you must define a series of tube elements that represent the flow location and direction. These are typically placed at some location above/below the plate. If you are going to have more than one discreet flow, place all tube elements from each flow on a separate layer. Use the Create Layer command to create a layer, then choose that layer when creating the elements, or use the Modify, Layer command to change it later. Unlike most general modeling techniques in FEMAP, tube elements are required for this special capability. In most cases, where these tubes are simply a modeling convenience and do not represent a physical tube with thermal properties, you will not want them to be written to your Nastran model. In that case, just define both the inner and outer diameters of the tube property as 0.0 - this indicates that you want the tube to be skipped during translation. If you do want the tube to be translated, just specify nonzero diameters. If you need to use tube elements in your model that are not being used to represent flow tubes, you MUST place them on a layer that is not used by any of the forced convections that you will later apply to the plate elements. If you do not, FEMAP may create improper links that do not represent the situation that you are attempting to represent. 3. Model the mass flow. The mass flow is modeled by applying forced convections to each of the flow tube elements. For all of these loads you must check the Disable Convection option. This will result in a load that simply models the mass/energy transfer down the flow stream, and not the convection effects. You must specify a flow diameter on these loads. Even though it is not required for the mass transfer equations, it is necessary to properly connect the convections from the plate. Typically you will want to specify a value that is near (or at least the same order of magnitude) the flow diameter for the plate convections. 4. Model the convection on the plate. Next, apply forced convections to the plate elements where the flow is occurring. All forced convections on plate elements are placed on Face 1, flowing from the middle of the first edge of the plate to the middle of the third edge (to the opposite node for triangular plates). If you created your elements in a manner where this does not really represent the direction of your flow you should use the Modify, Update, Reverse command, and the Align First Edge to Vector option to realign your plates so that the flow is properly represented. This is the step that can become very difficult if you have an arbitrary (non-rectangular or nonmapped) mesh. It is very important that as they are displayed, all of these convections on the plate point along the general flow direction. On all of these plate convections you should check the Disable Advection option. This will effectively eliminate the mass transfer, and indicate that you are trying to associate this load with a flow tube. You must also specify the flow diameter (hydraulic diameter). This diameter will be used in the calculation of the Reynolds number. In addition, when you check this option you will see an additional option displayed that is titled Area Factor. If you do not specify anything here, FEMAP uses the plate areas to compute coefficients in the heat transfer equation. By specifying a value you can scale that computation to allow for fins or any other area correction that you wish

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to apply. If you are working with multiple discreet flows, once again you must use the FEMAP layer capability to assign these convections to a flow number. Set the convection load layer to the same ID as that of the associated flow tubes. Links Created by Nastran Translator

Flow Tube with Advection

Convection on Plate

Specify additional fluid/heat transfer options. Go to the Model, Load, Body command and choose the Heat Transfer button. This will display a dialog box where you can specify the fluid properties and other flow parameters. Currently only one fluid and set of parameters can be specified. 5. Translate to Nastran. When you translate these loads to Nastran, the translator creates Plot-Only elements to represent the CHBDY elements that are required, and also create the links shown above. These links represent how each of the “convection only” plates are linked to the “advection only” flow tubes. Also, during the translation you will be asked to specify a factor that is used to disable the convection and advection. Since Nastran really has no way to disable these portions of the problem, we simulate this effect by scaling the appropriate components downward by the scale factor that you specify. Make sure that you always specify a small number ( 0 where X j(t) ≤ 0 A

where X j(t) < 0 where X j(t) ≥ 0

The other options simply define the arguments to these equations. In all cases, you must specify a scale factor. The X(t) arguments represent the displacement or velocity at node/DOF j (the first node) or k (the second). For Tabular Function loads, you must define and select a force vs. displacement/velocity function which will be used by the analysis program to calculate the force. Since FEMAP does not currently contain a “vs. Force” function, any function type can be used, but it should contain the appropriate force values. The nodal degrees of freedom must be specified as 1 through 6. For the Positive and Negative Power relationships, power is the exponent, A, of the equation shown.

4.3.3.6 Model, Load, Enforce Motion ...enables you to define a base acceleration. This option creates a base mass, links it to a set of “base nodes” in your model with a rigid element, and applies an equivalent base force. To begin you specify coordinates for the base mass using the standard coordinate definition dialog box. A node will be automatically created at this location. The next dialogue box is the standard entity selection box, which asks you to choose the nodes on the base. A rigid element is then created with the newly generated node as the independent node and the selected nodes as the dependent nodes. Next you define the base acceleration using the standard load creation dialog box. The type of load to create will be limited to either acceleration or rotational acceleration. You must choose a time or frequency dependent function to associate with the acceleration. The final required input is the mass and the acceleration scale factor. They are utilized to generate a nodal force (force = base mass * specified acceleration) at the independent node of the newly created rigid body. The values are automatically computed based on your current model and the acceleration that you chose. The default for the mass value is several orders of magnitude larger than the mass of the current model so the large mass will drive the rest of the model. You can either simply press OK to accept them, change them here, or edit the force later with the Modify, Edit commands.

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4.3.4 Geometric Loads As an alternative, and/or supplement to finite element loads, FEMAP allows you to create loads on geometry. Since analysis programs require loads directly on nodes and elements, FEMAP will convert these loads to nodal and elemental upon translation. Defining loads by geometry can greatly simplify load input, especially in complex solid models. It also provides a convenient method of load distribution, since a many times you will know the total load on a surface. FEMAP will automatically distribute that load over the surface based upon the area of the elements. Geometric loads also offer the advantage of storing equations and methods of direction. When you create a variable geometric load, FEMAP will store the equation and evaluate it upon translation. You can also request to “expand” geometric loads to individual nodal or elemental loads for visual verification or permanently (see Section 4.3.4.4, "Model, Load, Expand..."). The geometric load section contains four commands, based upon the type of load to create. They are On Point, On Curve, On Surface, and Expand. The first three commands enable you to create a load on the selected geometric entity, while the fourth command allows you to convert between FEA (nodal/elemental) and geometric (point/ curve/surface) loads. Each of these commands are discussed in more detail below.

4.3.4.1 Model, Load, On Point... ... allows creation of loads directly on points. The type of loads available are identical to those that are available through the Model, Load, Nodal command. All loads are converted directly to nodal loads upon translation or expansion. Most often you may want to simply use Model, Load, Nodal to create nodal loads directly. There are two major advantages of using this method over the Model, Load, Nodal command. The first is the ease of picking the correct entities. Points will typically be one of the first entities created in your model, even before any FEA entities are created, which will make selecting the points relatively simple. Also, you will generally have fewer points than nodes in your model, which again simplifies the selection process. The second advantage is that you can create a variable load which stores the equation and can then be easily modified.

4.3.4.2 Model, Load, On Curve... ...creates loads on curves, which are then converted to nodal or elemental loads (based upon the type of load) upon translation or expansion. This section documents unique features of loads on the curves. It does not go into detailed explanation of the input values for each type of load. For more detailed information on the specific inputs for each load type, see Section 4.3.3.2, "Model, Load, Nodal" or Section 4.3.3.4, "Model, Load, Elemental...".

FEA Attachment All loads on curves must be eventually expanded to nodal or elemental loads when translated to a finite element analysis program. When FEMAP expands the loads on curves into elemental or nodal loads, it creates loads for nodes or elements that were originally from that curve during a meshing procedure (or manually attached). This procedure is relatively simple for nodal loads. FEMAP determines which nodes are attached to the curve and creates the loads on these nodes. The only item which may alter this calculation is if you have turned on Midside Node Adjustment (see "Midside Node Adjustment"). For loads converted to elemental loads, only 2-D elements can be attached to the curve. For an element to be attached to the curve, all nodes on a face of an element must be attached to that curve. If a parabolic element is along a curve, but the midside node has been detached from that curve for some reason, the element is not considered to be on the curve.

Load Types There are 33 loads available for loads on curves. Many of the load types, such as force, force per length, and force per node are just different input methods for the same nodal load type (force). These different input methods enable FEMAP to distribute loads along the curve.

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The listing in the dialog box of the load type are separated into four sections: structural loads, temperature, heat transfer loads, and fluid loads. All structural loads except pressure are converted to nodal loads. Temperature is converted to a nodal temperature while elemental temperature obviously is an elemental load. The heat transfer loads include loads which will be converted to nodal loads (heat flux, heat flux per length, heat flux at node, and heat generation) or elemental nodes (element heat flux, convection, radiation, and element heat generation). There are 10 fluid loads that are scalar quantities and can only be accessed through the neutral file for use in analysis.

Load Input Values There are also three basic types of load input values: Total, Per Length, and Per Node. The “total” loads include force, moment, and heat flux. Input is a total load that is then automatically distributed along the nodes attached to the curve. The distribution will be based upon the total length associated with each node. Total loads must be input as constant. They cannot be variable. Loads input as “per length” loads (force per length. moment per length, and heat flux per length) are very similar to “total” loads. The load is distributed identically to a “total” load, except the values are then multiplied by the length along the curve associated with each node. The sum of all these loads is simply the input value multiplied by the total length of the curve. These types of loads must also be input as constant. All other loads are input on an “per node” basis. These include force per node, moment per node, heat flux per node, and translational and rotational displacements, velocities, and accelerations. These values are applied directly to the node with no distribution. This load type is most commonly used for displacements, as well as variable loading conditions for forces. If you have a load which varies along the length of the curve, this type of load input will allow you to describe an equation or function to simulate that loading condition. Total Load Only available for Force and Moment load types applied to curves. Allows you to enter the “Total” Force or Moment to be applied over all selected curves, not applied to each curve. Uses curve length to spread the load out proportionally. Total Load is the default for these load types when more than one curve has been selected. Direction Structural loads (i.e. force, force/length, etc.) which are converted to nodal loads upon expansion require input of the direction. The direction is identified identically to the specification of nodal load direction (see Section 4.3.3.2, "Model, Load, Nodal") with two small differences. The first is that the Direction method is saved. FEMAP does not convert the loads into components until you expand or translate. Therefore, if you list or modify these loads, you will see the same direction method you originally specified. Secondly, if you choose the Along Curve method, you cannot specify the curve. FEMAP will automatically use the curve(s) to which the loads are applied. Method The Method allows you to choose between a constant or variable load. If constant loading is required, simply choose Constant and input the values. If Variable loading is required (not available for “total” and “per length” loads), you must select Advanced, which allows you to define the type of definition for your variable load: Equation, Function, or Interpolation.

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Note: A variable load is only available for elemental loads and nodal loads that are “per node”. Nodal loads that are total (i.e. force, moment, etc.) and per length (force per length, etc.) must be constant. Equation Equation allows you to specify a variable loading in terms of the x, y, and z positions of the nodes or elements. Each of these values may be used in the equation definition, preceded by an !. For example 4.35*!x - 2*!y would multiply the x coordinate of each node (or element) and then subtract the product of 2 and the y coordinate. The x, y, and z coordinates are in the coordinate system defined in the main load dialog box. For instance, if you were working in a cylindrical coordinate system, x would be the radial coordinate, y the theta coordinate, and z the coordinate in the Z-axis. FEMAP will store the equation, and evaluate it only upon translation or expansion. The variable i is not used for loading on geometry, therefore all functions such as XND, and XEL are not applicable and should not be used. Note: The node locations are used to evaluate the equation for all loads converted to nodal loads. The position of the centroid of the elemental face attached to the loaded curve is used for all elemental face loads while the centroid of the element is used for non-face loads such as elemental temperature and elemental heat generation. The only exception is FEMAP will use the node locations to calculate pressure if the At Corner option for pressures is selected. Function The second type, Function, allows you to define a function to describe the loading. This function must be created before defining the load by using the Model, Load, Function command. Two types of functions are acceptable for variable loads on curves: vs. curve length, and vs. curve parameterization. Simply create this type of function with the load value as Y, and the X value as either the length along the curve, or the parameter value. By creating a function, you can model any irregular load pattern over the curve. FEMAP will use the position of the node, element face centroid, or element centroid and linearly interpolate a value at that position from the function. FEMAP does not perform any extrapolation of these values. Therefore, if a load occurs over the entire length of the curve, you should take care to define the values of the curve at the beginning and end points. Interpolation The third type, Interpolation, is really a shortcut version of Function. When you select Interpolation, the Locate 1 and Locate 2 areas become accessible. You can then select Locate for 1 and 2 and the standard coordinate definition dialog box will appear. You simply define the two locations and then define the load values associated with them. FEMAP will interpolate between these values to obtain loads on the nodes or elements attached to the curve. Once again, FEMAP will perform no extrapolation. This is a useful method for defining loads on a segment of a curve.

FEA Attachment All loads on curves must be eventually expanded to nodal or elemental loads when translated to a finite element analysis program. When FEMAP expands these loads, it creates loads for nodes or elements that were originally

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generated from that curve during a meshing procedure (or manually attached). This procedure is relatively simple for nodal loads. FEMAP determines which nodes are attached to the curve and creates the loads on these nodes. The only item which may alter this calculation is if you have turned on Midside Node Adjustment (see "Midside Node Adjustment"). For loads converted to elemental loads, both 2-D and 3-D elements can be attached to the Surface. IF FEMAP finds faces of 2-D and 3-D elements that are identical, FEMAP will expand the load on the 2-D element, and issue a warning message. The only exception to this procedure is if the 2-D elements are plot-only planes. For an element to be attached to the surface, all nodes on a face of an element must be attached to that surface. If a parabolic element was created on a surface, but midside nodes have been detached from that surface for some reason, the element is not considered to be on the curve. Note: Loads are not expanded on plot-only planar elements since these elements are not translated as structural elements. Loads cannot be applied to these elements. Midside Node Adjustment Some methods such as force/length and force distribute the loads over the entire length. For many parabolic elements, you cannot simply distribute the force evenly and obtain an even displacement result. You must apply a larger value to the midside nodes than the corner nodes, and this value is in excess of 1/2 the value of the total load on the element. You can specify the factor you want on the midside nodes under File Preferences, Geometry, on the Edge Factor. This value defaults to 2/3, which is standard for many programs. This means that 2/3 of the load will be applied to the midside node, and 1/6 to each corner node. If your results are inappropriate for your analysis program, please consult the documentation for your program. You can also remove the option to adjust for midside nodes by clicking this option off.

4.3.4.3 Model, Load, On Surface... ...creates loads on surfaces, which are then converted to nodal or elemental loads (based upon the type of load) upon translation or expansion. This section documents unique features of loads on surfaces. It does not go into detailed explanation of the input values for each type of load. For more detailed information on the specific inputs for each load type, see Section 4.3.3.2, "Model, Load, Nodal" and Section 4.3.3.4, "Model, Load, Elemental...".

FEA Attachment All loads on surfaces must be eventually expanded to nodal or elemental loads when translated to a finite element analysis program. When FEMAP expands these loads, it creates loads for nodes or elements that were originally generated from that surface during a meshing procedure (or manually attached). This procedure is relatively simple for nodal loads. FEMAP determines which nodes are attached to the curve and creates the loads on these nodes. The only item which may alter this calculation is if you have turned on Midside Node Adjustment (see "Midside Node Adjustment"). For loads converted to elemental loads, both 2-D and 3-D elements can be attached to the surface. If FEMAP finds faces of 2-D and 3-D elements that are identical, FEMAP will expand the load on the 2-D element and issue a warning message. The only exception to this procedure is if the 2-D elements are plot-only planes. Since plot only elements are not translated as structural elements, loads cannot be applied to these elements. For an element to be attached to the surface, all nodes on a face of an element must be attached to that surface. If a parabolic element was created on a surface, but midside nodes have been detached from that surface for some reason, the element is not considered to be on the curve.

Load Types There are 35 loads available for loads on surfaces. Many of the load types, such as force, force per area, and force at node are just different input methods for the same nodal load type (Force). These different input methods enable FEMAP to distribute loads along the surface. Two load types, Bearing Force and Torque are only available when applying loads to surfaces. Both use the Midside Node Adjustment and Total Load options by default. These options are explained in greater detail below.

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When creating a Bearing Force, enter a Magnitude, Load Angle (specifies the area in which the “bearing” is in contact, entered in degrees. 180 is the default), and Phase (if needed), then specify a vector to represent the direction of the load. Additionally, there is an option to have the Bearing Force be Normal to Surface (“on” by default), which will apply the loads radially to cylindrical surfaces. Also, the load may be a Traction Load (“off “by default), which will essentially have the load “pull” on a surface instead of “push”. For example, the 4 copies of a “block with a hole” geometry are all loaded with bearing forces using different options:

Bearing Force on single surface with “Normal to Surface” option “On”

Bearing Force on single surface with “Normal to Surface” option “Off”

Vector used to define bearing force

Bearing Force on multiple surfaces with “Total Load” and “Normal to Surface” options “On”

Bearing Force on multiple surfaces with “Total Load”, “Normal to Surface”, and “Traction Load” options “On”

Vector used to define bearing force

When expanded, Bearing forces will have varying values:

Bearing Forces from above shown Expanded (Load values and mesh not shown clarity)

When creating a Torque load, enter a Magnitude and Phase (if needed), then specify a vector representing the axis the load acts about.

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The listing in the dialog box of the load type are separated into four sections: structural loads, temperature, heat transfer loads, and fluid loads. All structural loads except pressure are converted to nodal loads. Temperature is converted to a nodal temperature, while elemental temperature obviously is an elemental load. The heat transfer loads include both nodal (heat flux, heat flux per length, heat flux at node, and heat generation) and elemental nodes (element heat flux, convection, radiation, and element heat generation). There are 10 fluid loads that are scalar quantities and can only be accessed through the neutral file for use in analysis.

Load Input Values There are also three basic types of load input values: Total, Per Area, and Per Node. The total loads include force, moment, and heat flux. Input the total load value, and FEMAP will automatically distribute it over the surface. The distribution will be based upon the total area associated with each node. Total loads must be input as constant. They cannot be variable. Loads input as “per area” loads (force per area, moment per area, and heat flux per area) are very similar to “total” loads. The load is distributed identically to a “total” load, except the values are then multiplied by the area associated with each node. The sum of all these loads is simply the input value multiplied by the total area of the elements. These types of loads must also be input as constant. All other loads are input on a “per node” basis. These include any “per node” loads as well as translational and rotational displacements, velocities, and accelerations. These values are applied directly to the node with no distribution. These are most commonly used for displacements and variable loading conditions. If you have a load which varies over a surface, this type of load input will allow you to input an equation to simulate the loading condition. Total Load Only available for Force, Bearing Force, Moment, and Torque load types applied to surfaces. Allows you to enter the “Total” Force, Bearing Force, Moment, or Torque to be applied over all selected surfaces, not applied to each surface. Uses surface area to spread the load out proportionally. Total Load is the default for these load types when more than one surface has been selected. When used, “Total” will appear in the default Load Definition title. Direction Structural loads (i.e. force, force/length, bearing force, etc.) which are converted to nodal loads upon expansion require input of the direction. The direction is identified identically to the specification of nodal load direction (see Section 4.3.3.2, "Model, Load, Nodal") with two differences. The first is that the Direction method is stored. FEMAP does not convert loads into components until you expand or translate. Therefore, if you list or modify these loads, the same direction method is shown. Second, if you choose the Normal to Surface method, you cannot specify the surface. FEMAP will automatically use the surface(s) to which the loads are applied. Method The Method allows you to choose between a constant load or a variable load. If a constant load is required, simply choose Constant and input the values. If a variable load is required (not available for “total” and “per length” loads), you must select Advanced and select the Equation method. The Function and Interpolation methods are not available for loads on surfaces.

Note: A variable load is only available for elemental loads and nodal loads that are “per node”. Nodal loads that are total (i.e. force, moment, etc.) and per area (i.e. force per area, etc.) must be constant. Equation Equation allows you to specify a variable loading in terms of the x, y, and z positions of the nodes or elements. Each of these values may be used in the equation definition, preceded by an !. For example 4.35*!x - 2*!y

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would multiply the x coordinate of each node (or element) and then subtract the product of 2 and the y coordinate. The x, y, and z coordinates are in the coordinate system defined in the main load dialog box. FEMAP will store the equation, and evaluate it only upon translation or expansion. For instance, if you were working in a cylindrical coordinate system, x would be the radial coordinate, y the theta coordinate, and z the coordinate in the Z-axis. The variable i is not used for loading on geometry, therefore all functions such as XND, and XEL are not applicable and should not be used. FEMAP stores the equation and only evaluates it when the load is expanded upon translation or when the Model, Load, Expand command is used. Note: The location of the nodes are used to evaluate the equation for all loads converted to nodal loads. The position of the centroid of the elemental face is attached to the loaded curve is used for all elemental face loads. The position of the centroid of the element is used for non-face loads such as elemental temperature and elemental heat generation. The only exception to the above is FEMAP will use the position of the nodes to calculate pressure loads if you select the At Corner option for pressures. Midside Node Adjustment Some loads such as force/area and force distribute the loads on the nodes over the entire area. For many parabolic elements, you cannot simply distribute the force evenly and obtain an even displacement result. You must apply a larger value to the midside nodes than the Corner nodes, and this value is in excess of 1/2 the value of the total load on the element. You can specify the factor you want on the midside nodes under File, Preferences, Geometry. There are two factors available for Midside Node Adjustment, Tri-Face and Quad-Face factors. These value represent the percentage of the load on each midside node. The values default to 1/3. which means for tri-faces, no loads are applied to the corner nodes, and a -1/12 factor is applied to quad-face corner nodes. These values are standard for many programs. If your results are inappropriate for your analysis program, please consult the documentation for your program. You can also remove the option to adjust for midside nodes by clicking this option off.

4.3.4.4 Model, Load, Expand... ...enables you to visualize the nodal and elemental loads which will be created from geometric loads. This command operates only on the current active load set. When this command is selected, you will see the following dialog box. The Model, Load, Expand command can be used to either expand or compress the geometric loads. When using it to expand loads, you have the option to specify which loads to expand (On Point, On Curve, On Surface) or to expand the entire set (All in Set). If you select an option other than All in Set, the standard entity selection box will appear. When compressing loads, individual types of loads cannot be selected. Compression is always performed on the entire set. If a load has already been expanded, and you select to expand it again, or expand the entire set, an error message will be supplied and the load will not be expanded a second time. This procedure prevents duplication of loads. When translating to an FEA model, to prevent duplication, and to evaluate all loads with their current equation, all loads used in the translation will be compressed, then expanded through the translator, and finally compressed again after translation. Therefore, any expanded geometric loads which appear as elemental or nodal loads before expansion, will be converted back to geometric loads. Convert To Node/Elem This option allows you to permanently convert the selected loads to nodal/elemental loads. Be careful when using this option, because you cannot convert back to the original geometric loads. This option can be useful when a load is mostly constant (or easily described as an equation) over a surface, except at a few nodes (or elements). You can permanently expand the load, and then use the Modify, Update Other, Scale Load command to change individual loads.

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Combined Nodal Loads When FEMAP expands multiple geometric loads, it will attempt to combine all similar nodal loads into one load for each DOF. Many analysis programs require only one load on a DOF. With loads such as forces and moments, FEMAP will add the components. The only exception is if the loads contain either different vs. time/temp/freq reference functions, different phases, or different freq reference functions for the phase. In these cases, the loads will remain separate and a warning message will be written. For loads such as displacement or acceleration, FEMAP will not add values for the same DOF. It will keep these values separate and provide a warning message that two different values were found for the same DOF. You will need to modify the input to obtain the desired values at the nodes. The option to permanently convert to nodal loads could be used in this case to expand and then modify the displacements on the nodes.

4.3.4.5 Model, Load, Bolt Preload... ...creates a load representing a “Bolt Preload” for NX Nastran. The Bolt Preload is available for use in Linear Static Analysis, Modal Analysis, Buckling, and Advanced Nonlinear Analysis (Solution 601). The Create Bolt Preload dialog box allows you to enter a title which will used as the Load Definition title and assign a color and layer for each Bolt Preload. Each Bolt Preload must be associated with a Bolt Region. The Bolt Region can be created prior to creating the Bolt Preload, or elements can be chosen in this dialog box and the Bolt Regions will then be created automatically. You must choose the entity type (Bolt Region(s) or Element(s)) and specify the Preload value before you can actually choose the entities to apply the load. Currently, Bolt Preloads can only be applied to Beam and Bar elements. If you choose multiple elements to apply Bolt Preloads, FEMAP will combine any selected elements which are “connected” into a single bolt region. This is actually very useful when creating Bolt Preloads as you can choose all of the Beam or Bar elements in a model otherwise consisting of solid or shell elements. In this case, each “connected set” of beam/bar elements will become and individual Bolt Region with appropriate Bolt Preload. Note:

FEMAP will allow you to choose ANY type of element when selecting elements for applying a Bolt Preload. If any of those elements are not the right type of element (Bar and Beam elements ONLY for FEMAP 9.3 and NX Nastran 5), they will not be added to the list and an error message stating “Skipped ‘#’ of Elements which have invalid types for this command” will be sent to the Messages window.

4.3.5 Load Analysis Options These three commands enable you to set options for different analysis types. Three commands are available, based upon the type of analysis required: heat transfer analysis, dynamic analysis, and nonlinear analysis. These commands are not used to put loads onto the model. Rather, they simply define certain parameters which are required for the analysis type. The options contained in each of these commands are discussed below. These commands are not used if you are performing simple static or modal analysis.

4.3.5.1 Model, Load, Nonlinear Analysis... ...defines the information that is typically required to perform a nonlinear analysis. While this information does not typically represent a load, it is included in the load menu because it does relate to the other loading conditions and how they will be applied. Each load set to be used in a nonlinear analysis must have the appropriate solution type activated.

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Finite Element Modeling Solution Type The solution type determines the type of solution that will be performed for the particular load set. Available options are Static, Creep, and Transient. Only appropriate control information in the remainder of the window will be available based upon the type of solution you choose. Basic These values provide the time and iteration control information for the nonlinear analysis steps. They control the Number of Increments and the Time Increment to be used, as well as the Maximum Iterations for each step. No time increment is used for static analysis.

Stiffness Updates This specifies the number of iterations to be performed before the stiffness matrix is updated, as well as the update Method. Five different update methods are available, but not all are appropriate for all each solution type. If an inappropriate method is selected, the translator will provide an error message and automatically choose the default method. Output Control Output Control information allows you to request or eliminate output at intermediate steps (static and creep) or request Output Every Nth Step (transient). Convergence Tolerances The type of Convergence Tolerances (Load, Displacement, and/or Work) as well as the tolerance values themselves are defined in these boxes. Solution Strategy Overrides This area provides you with the capability to further control the strategy that will be employed to converge toward a solution. Defaults When you first choose this command, all values will be zero. By pushing this button, nonzero default values will be entered for all properties. You can then modify these defaults as appropriate. Copy Copy allows you to duplicate the nonlinear analysis information from any other load set in the current model. Advanced This button enables you to access additional nonlinear analysis options as well as damping inputs for nonlinear transient analysis. For most problems, the nonlinear options are not required, but they are available for experienced analysts to modify the default solution controls. The damping values for nonlinear transient analyses can be input here or under Model, Load, Dynamic Analysis.

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Using Advanced Options with NASTRAN The options in the Advanced Group, when written to Nastran, are used to define the parameters on the NLPARM statement. In general, FEMAP does not distinguish between blanks and zeros when you enter values into dialog boxes, therefore, when the values are written to Nastran it is normally not possible to control whether a blank or a zero will be written. For some of these fields however this distinction is important, therefore several special cases have been implemented. If you specify a blank, or zero, in the dialog box for any of these cases, you will get a blank in your Nastran file. If you specify a negative value for Quasi-Newton Vectors, or for Max Line Searches/Iter, you will get a “0”. Similarly, if you specify a value that is less than -10, for Max Bisections / Increment, you will get a zero. Values less than -10 were chosen because values down to this value are valid for that field.

4.3.5.2 Model, Load, Dynamic Analysis... ...provides the solution type and control information for dynamic analyses. Each load set to be utilized in a dynamic analysis must have the appropriate solution method activated. In addition, a dynamic analysis load is required for nonlinear transient analysis to define structural damping.

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Solution Method The solution method chooses the type of dynamics solution to be performed. Four available options exist: Direct Transient, Modal Transient, Direct Frequency, and Modal Frequency. The inappropriate boxes for each Solution Method will be grayed automatically. Equivalent Viscous Damping This box provides damping information for the structure. The Overall Structural Damping Coefficient is input for all four solution methods, while the Modal Damping Table is utilized for only the two modal methods. The Modal Damping Table requires a function to define damping information as a function of frequency. Three types of FEMAP functions can be chosen: Viscous Damping vs. Frequency, Critical Damping vs. Frequency, and Amplification vs. Frequency. You can create a Function directly from this dialog box by clicking the Function Icon Button. Equivalent Viscous Damping Conversion Information for both system damping and element damping is provided in this box. These values are only input in direct and modal transient Analysis. These values provide the conversion from the frequency domain, in which damping is usually defined, into the time domain. The Frequency for System Damping (W3 - Hz) is divided into the overall damping coefficient (for Nastran and ANSYS), or the material damping values for each material (for ABAQUS and LS-DYNA) and then multiplied by the stiffness to obtain element (or stiffness) damping. The Frequency for Element Damping (W4 - Hz) is used in combination with the material damping values to obtain structural damping in Nastran, and mass damping in ABAQUS, ANSYS, and LS-DYNA. Response Based On Modes For the modal solution methods, these options allow you to choose the number and/or range of modes to include in the frequency response or transient formulation. Transient Time Step Interval For transient analyses, these options control the number of steps, size of steps, and the output interval. If this load is to be used in a nonlinear transient analysis, these options are overridden by the nonlinear transient time step input. Frequency Response The Solutions Frequencies table is chosen in this section. This table defines the frequencies to be analyzed for both direct and modal frequency analysis. The frequency table is just a function with a list of frequencies in the X position. The y position is irrelevant and will be ignored. A solution frequency table can be automatically created by pressing the Modal Freq button. If you are using Nastran, you may also select the Advanced option to define the range of solution frequencies. You can create a Function directly from this dialog box by clicking the Function Icon Button. Random Analysis Options This option allows you to define a Power Spectral Density (PSD) function to be used for random analysis. You simply use the Model, Function command to define the PSD values as a function of frequency (a vs. frequency function type), and then select this function under Random Analysis Options. This option is used only for random response analysis. You can create a Function directly from this dialog box by clicking the Function Icon Button. Modal Freq If you have previously performed a modal analysis on your model, and have the solution information in the current model, you can automatically create a solution frequencies function/ table from that output. Simply press Modal Freq, and you will see the following: The modal frequency in each output case will be selected for the Solution Frequency table. Additionally, frequencies in a band near each modal frequency can be chosen by using the Additional Solution Frequency Points. The Number of Points per Existing Mode defines the number of frequencies to be included for each modal frequency, while the Frequency Band Spread defines the placement of the additional frequencies. Choosing only one point per mode will select just the modal frequencies. Choosing three points per mode will select the

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modal frequencies and two additional frequencies at the modal frequency plus and minus the spread value. The number of points must always be odd so that the modal frequencies are selected. Enforced Motion Pressing the Enforced Motion button enables you to define a base acceleration. This option creates a base mass, links it to a set of “base nodes” in your model with rigid elements, and applies an equivalent base force. To begin you specify coordinates for the base mass using the standard coordinate definition dialog box. A node will be automatically created at this location. The next dialogue box is the standard entity selection box, which asks you to choose the nodes on the base. A rigid element is then created with the newly generated node as the independent node and the selected nodes as the dependent nodes. Next you define the base acceleration using the standard load creation dialog box. The type of load to create will be limited to either acceleration or rotational acceleration. You must choose a time or frequency dependent function to associate with the acceleration. The final required input is the mass and the acceleration scale factor. They are utilized to generate a nodal force (force = base mass * specified acceleration) at the independent node of the newly created rigid body. The values are automatically computed based on your current model and the acceleration that you chose. The default for the mass value is several orders of magnitude larger than the mass of the current model so the large mass will drive the rest of the model. You can either simply press OK to accept them, change them here, or edit the force later with the Modify, Edit commands. Advanced As with nonlinear analysis, an Advanced button is provided to give experienced analysts more control over the solution strategy. The following dialog box is provided to enable choices for Mass Formulation and Dynamic Data Recovery.

You can also specify addition analysis inputs for Solution Frequencies and Random Response Analysis. Solution Frequencies / Additional Frequencies This option provides an alternative method to the Solution Frequencies function on the main Dynamic Analysis dialog box. The Solution Frequencies section defines the first set of frequencies defined on a FREQi card. An additional set of frequencies with all the same options as in the first frequency set can be defined in the Additional Frequencies section. If additional frequencies are defined, then a second FREQi card will be used. This is currently only supported for Nastran. If you have selected a direct frequency analysis, only the Default List and the Frequency Range (Min, Max, No. of Intervals) options will be available, although logarithmic interpolation can also be employed for the frequency range. If you select Modal Frequency as the analysis type, additional types to determine the solution frequencies from the natural modes will be available. These are Cluster around Modes, which corresponds to the Nastran

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FREQ3 card, and Spread Around Modes (Nastran FREQ4 card). Cluster around Modes will also have a logarithmic interpolation option. Random Analysis There are currently two options supported for random analysis. The first is the ANSYS PSD type: ANSYS has the capability to input acceleration (in g2/Hz or acc units2/Hz, displacement, velocity, or force). By simply changing this option, the type of input on the PSD Function in the main Dynamic Analysis dialog box is modified. The second is Nastran PSD Interpolation: Nastran has the ability to define the PSD table in the following four formats... (Log, Log), (Linear, Linear), (X Log, Y Lin), (X Lin, YLog). By simply changing this option, the type of Interpolation used on the PSD table input (Nastran TABRND1) in the main Dynamic Analysis dialog box is modified. Mass Formulation Specifies the solver to use Lumped or Coupled Mass Formulation in Dynamic Analysis. By default, Nastran generates “Lumped” mass matrices (PARAM,COUPMASS,-1). Choosing Coupled instructs Nastran to generate “Coupled” mass matrices for elements with coupled mass capability (PARAM,COUPMASS,1) Copy This selection allows you to copy dynamic analysis options from any other load set in the current model.

4.3.5.3 Model, Load, Heat Transfer Analysis This command enables you to define heat transfer constants, thermal characteristics for convection, and select the type of formulation to use for different types of heat transfer problems. Radiation If you are going to perform a radiation analysis, you must specify the temperature difference between absolute zero and zero in the temperature system that you are using, and the Stefan-Boltzmann constant. Free Convection For free convection analysis, you can choose between two alternative forms of the free convection temperature exponent. They are

Standard q = h × u CTRLND × ( T – T AMB ) Alternate q = h × u CTRLND × ( T

EXPF

EXPF

–T

× ( T – T AMB )

EXPF

AMB )

The Convection Exponent is the value shown as EXPF in the above equations. These options are currently used for NX Nastran and MSC.Nastran only. Forced Convection The forced convection values specify the properties and behavior of the fluid to be analyzed. These options correspond directly to the options on the Nastran PCONVM and MAT4 commands. Refer to the Nastran documentation for more information about the proper values for these options.

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4.3.6 Load Set Manipulation This section of the menu works to create either additional load sets or new loads from output. There are four commands available: Copy, Combine, From Output, and From Freebody. Each command is briefly discussed below.

4.3.6.1 Model, Load, Copy... ... duplicates the active load set. All loads, including body, nodal elemental, and geometric loads are copied to the new set. If you do not want to duplicate all of them, use the Delete, Model, Load commands to remove the ones that you do not want from the new set. Input for this command is minimal. Simply specify the ID of the load set that you want to create. This new set must not exist. FEMAP will create a duplicate copy of the active set with the ID that you specify. After the copy has been made, FEMAP will ask whether you want to activate the new set. Answer No if you want to continue working with the original load set. Answer Yes to work with the new copy. Hint:

You may want to use the Model, Load, Create/Manage Set command to modify the title of the new copy. FEMAP will always create it with the same title as the original set that was copied.

4.3.6.2 Model, Load, Combine... ... enables you to combine two or more load sets into one new load set based upon the following formula Load = A 1 Load 1 + A 2 Load 2 + … + A n Load n

Choose any number of load sets from the From list (Hold the CTRL key when you click to choose multiple load sets one at a time or the SHIFT key to choose a range of Load Sets), then enter a Scale factor (Default is “1”), then select an existing Load Set to place the load combination when finished (or use the default “0..New Set” to create a new load set). If you are creating a new load set, you can give the new “combined” Load Set a title. Once the Load Set(s) are selected from the From list, the scale factor and To are set, click Add Combination to add the selected Load Sets to the Combinations list. You will notice that the scale factor will proceed the Load Set number and title when placed in the list. You can use the Remove Combination button to remove any number of load combinations from the Combinations list. Temperature loads will not be linearly combined. FEMAP will simply copy the nodal and elemental temperatures. If conflicting temperatures exist for the same node or element in the individual load sets, FEMAP will use the last temperature. Also, If loads exist on the same node or element in different sets that are combined, the resulting set will simply obtain multiple loads on that node or element, which can then be combined with Tools, Check, Coincident Loads.

4.3.6.3 Model, Load, From Output... ... lets you convert output data from one or more output vectors into various load types. The loads are always created in the active load set. When you choose this command, FEMAP displays a dialog box to let you choose the type of load you want to create. After you make a selection, and press OK, the Create Loads From Output dialog box will be displayed. If you are creating nodal or elemental temperatures, pressures or heat transfer loads, you will be able to specify an output set and output vector which contains the temperature data. For other types of loads, six vectors can be selected.

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Data from the six vectors will be converted to the six loading degrees of freedom. If you leave any vectors blank (or zero), no loads will be created in that direction. You must always specify at least one vector. When creating elemental pressures, or many of the elemental heat transfer loads, you must also specify a Face ID where the load will act. You cannot create output on different element faces at the same time with this command. Also, all loads are created in global rectangular coordinates, therefore the output must also be in global rectangular. You can choose the Color and Layer for all new loads. Finally, after you complete these options and press OK, the standard entity selection dialog box will be displayed. You must select the nodes or elements where loads will be created. You can either select your entire model, in which case all output will be converted, or limit the conversion to some selected portion of your model. In either case, loads will only be created if output exists for a particular node or element.

Why Create Loads from Output? The primary reason to convert output data to load data is for use in future analyses. For example, you may want to convert that data to temperature loads from a heat transfer run in a structural analysis. Similarly, you might want to use displacement, force or acceleration output from one structural analysis as a loading condition for further analyses.

Converting Between Nodal and Elemental Temperatures Another reason to use this command is to convert nodal to elemental temperatures, or vice versa. If you have defined temperatures and need to convert them to the opposite type, this command can be combined with several others to accomplish that task. First, convert your current temperatures to output data using Model, Output, From Load command. Then use Model, Output, Convert to create an additional output vector of the opposite type. Finally, use Model, Load, From Output and select the vector created with Model, Output, Convert.

4.3.6.4 Model, Load, Map Output From Model... ... lets you “map” certain output data from 2-D elements on one model (Source) onto another (Target). The two models can have completely different meshes and FEMAP gives you a few options for the method used to “map” the output. There are a few things required for this command to be used effectively: 1. You must have both the “Source” and the “Target” models open in the same instance of FEMAP 2. The “Source” model must have output which can be “mapped” onto the nodes of a “Target” model. Output which can be “mapped” is restricted to the output types listed in the Nodal or Elemental drop-down lists for 2-D elements only (Quad and Triangular elements) 3. The “Source” model must have a group containing all the elements which have output data to be “mapped” onto the nodes or elements of the “Target” model.

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Output to Map All fields must have values for this command to function properly. You will know you have enough data in your “Source” model if all the drop-down menus have selectable values. From Model This menu allows you to choose a Model to use as your “Source” model for the “mapping” process. If you have more than 2 models open inside one instance of FEMAP, all of the other models except the current model will appear in the From Model drop-down menu. Results on Group This menu allows you to choose a Group in the “Source” model to use for the “mapping” process. If you have multiple groups in your “Source” model, all of the groups will appear in the Results on Group drop-down menu. The group can only contain 2-D elements (Quad and Triangular elements) Output Set This menu allows you to choose an Output Set in the “Source” model to use for the “mapping” process. If you have multiple output sets in your “Source” model, all of the output sets will appear in the Output Set drop-down menu. Output Vector This menu allows you to choose an Output Vector in the “Source” model to use for the “mapping” process. Only available Output Vectors in the “Source” model will appear in the Output Vector drop-down menu. Values for Locations with No Map This menu allows you to choose a “mapping” option for entities which do not have a “one-to-one mapping” from the “Source” to the “Target”. When a node is not “mapped” it is because a “Target” node’s normal projection does not fall within any “Source” Element. The options for nodes that are not mapped: •

0..Set to Zero - Sets all entities without a direct “map” to the value of zero (0.0)



1..Set to Value - Sets all entities without a direct “map” to a specified value. The value can be specified as a constant or in X, Y, and Z components.



2..Extend Closest - Extends the value to the closest “Target Entity”.



3..Interpolate - Does a linear interpolation using the source values. (Default)



4..No Output - Applies no output values to any entities which do not have a direct “map”. FEMAP will also automatically create a group of “Target” nodes which have not been “mapped”.

Map Tolerance When a “Target” location is projected onto the “Source” data surface and the distance to a discrete data point is less than the tolerance, the “Source” value of the "coincident" location is directly mapped to the “Target” without interpolation. If multiple nodes fall within this tolerance, then the first one encountered numerically will be directly mapped. Default value is the "Merge Tolerance" of the "Target” model. Target You can choose to “Map” Output to the target model using either the To Model Loads or To Data Surface method. When the To Model Loads option is used, loads of the chosen type (Forces, Displacements, or Temperatures on Nodes; Pressures or Temperatures on Elements) will be created directly on the target model’s nodes or elements in the current load set.

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When To Data Surface is used, FEMAP will create a new “Data Surface” to be used in any loading condition of the current model. The only input additional input for the To Data Surface method is Data Surface Name, which is optional, but recommended. The following figure shows an example of a common use for this command: Course Thermal model with Temperature output

Fine Structural model receives “mapped” Nodal Temperatures as a Load from Course Thermal model (temperature loads not displayed in figure for clarity)

Fine Structural Model with Nodal Temperatures displayed as output

Temperature Loads converted to Output for viewing of “Mapping” to closest node. Nodal Temperature Loads could also be used to perform Thermal Stress analysis

4.3.6.5 Model, Load, From Freebody... ...creates loads directly from a freebody display. You must have a Freebody entity defined in the model. Use the Sum Data on Nodes option in the Freebody tool of the PostProcessing Toolbox to display exactly what will be created in the “Active” Load Set. Depending on the Display Type of the selected Freebody entity, “Freebody” or “Interface Load”, the inputs after Freebody entity selection will be different. If Display Type = “Freebody”, the only additional input will be selecting nodes to create loads. If Display Type = “Interface Load”, two questions will be asked, “OK to Create Freebody Resultant Load?” and “OK to Create Freebody Individual Loads?”. If you choose to only create “Resultant” loads, there are no additional inputs and loads will be created on a new node at the Location of the Total Load Vector. If you choose to create only “Individual” loads or both types, then selection of nodes is required to specify where to create the “Individual” loads.

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4.3.7 Activate/Create Constraint Set All nodal constraints, constraint equations, and geometric constraints are created in the active constraint set. Therefore, you must always activate a constraint set prior to creating either of them.

4.3.7.1 Model, Constraint, Create/Manage Set...

Shift+F2

...displays the Constraint Set Manager. This menu command is also available on the tray at the bottom right portion of the graphics window, as well as by choosing New from the Constraints object context-sensitive menu in the Model Info tree. The Constraint Set Manager can be used to create new constraint sets; update the title of an existing constraint set; renumber, delete, or copy the active constraint set; as well as define “SPCADD/MPCADD sets” for Nastran. Create new Constraint Set Update the title of an existing Constraint Set Renumber highlighted Constraint Set Delete highlighted Constraint Set Delete all Constraint Sets Copy highlighted Constraint Set Define “SPCADD/ MPCADD Set” Deactivate All Constraint Sets

Title Filter

Clear Title Filter

To activate a constraint set that already exists, simply highlight it from the Available Constraint Sets... list. When a new constraint set is created, it will automatically become the “Active” constraint set. To deactivate all constraint sets, press None Active. Note: When a “combined” constraint set is “Active”, no constraints will be visible in the FEMAP graphics window, regardless of options set in the Visibility dialog box (View, Visibility) and Model Info tree. Creating New Constraint Sets To create a new constraint set, press the New Constraint Set button.

The next available constraint set ID will automatically be entered in the ID field when creating a new constraint set, but any constraint set ID not currently being used in the model may be entered instead. You may also enter a Title. As always, you should choose a descriptive title. The titles are displayed, along with the IDs, in the Available Constraint Sets - Selected Constraint Set is Active list of the Constraint Set Manager. Press OK to create a constraint set or press More to create a constraint set, then be prompted to make another.

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You may choose a Set Type for the new constraint set. A Standard constraint set is any combination of Constraint Definitions and Other Loads used to define the boundary conditions for that constraint set. A Nastran SPCADD/MPCADD Combination is a special type of constraint set which “references” any number of existing Standard constraint sets in the model. When used, all of the selected Standard constraint sets referenced by a particular Nastran SPCADD/MPCADD Combination are written to the Nastran input file and combined by Nastran via a SPCADD entry when dealing with normal constraints or a MPCADD when dealing with constraint equations. Once a Nastran SPCADD/MPCADD Combination Set has been created, highlight it from the list in the Constraint Set Manager and press the Referenced Sets button. The Referenced Constraint Sets for Nastran SPCADD/ MPCADD dialog box will appear:

Highlight any number of Standard constraint sets from the list of Available Sets. Click Add Referenced Set to have them placed in the Referenced Sets list. Note: A Referenced Constraint Sets command may be added to any menu or toolbar using the Tools, Toolbars, Customize command. This command is located in the Additional Commands category on the Commands tab of the Customize dialog box..

4.3.8 Constraint Definitions Every time a constraint is created on finite element entities (i.e., Model, Constraint, Nodal; Model, Constraint, Nodal on Face; and Model, Constraint, Equation) or geometry (Model, Constraint, On Point; Model, Constraint, On Curve; Model, Constraint, on Surface) a “Constraint Definition” will also be created in FEMAP. These Constraint Definitions will appear in the Constraints branch of the Model Info tree and can be given a title. Each Constraint Definition will contain all of the individual constraints which were created at the same time using a Model, Constraint... command. Constraint Definitions can then be edited, listed, and deleted and all individual constraints contained in that Constraint Definition will be edited, listed, or deleted. Note: Each Constraint Equation created will also create a new Constraint Definition. These Constraint Definitions can then be combined. Note: All of the commands for listing, deleting, and modifying individual constraints are still available in FEMAP. For example, if you chose to put a constraint for Degrees of Freedom TX, TY, and TZ on 5 selected nodes, a single “Constraint Definition” would appear in the Model Info tree. In this case, if the Constraint Definition were to be edited, 5 individual constraints would be modified using one command. Constraint Definitions can be removed at any time using the Remove Definition command on the context sensitive menu in the Model Info tree and the individual constraints from that Constraint Definition will be moved under the appropriate heading in the Other Constraints branch. The Other Constraints branch contains headings for On Geometry, On Mesh, and Equations.

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Also, a Constraint Definition can be created from any number of constraints of the same type (i.e., any number of Nodal Constraints, Constraints on Curves, or Constraint Equations, etc) by highlighting them in the Model Info tree and using the Create Definition command from the context sensitive menu. Note: If you combine multiple constraint equations into one constraint definition, you will be prompted to edit each constraint equation one at a time. If you choose constraints of various types and then use the Create Definition command, FEMAP will create a Constraint Definition for each separate type of constraint that was highlighted. For more information about the Remove Definition and Create Definition commands, along with the process of combining Constraint Definitions, please see Section 7.2.1, "Tools, Model Info" under “Loads and Constraints in the Model Info Tree”

4.3.9 Finite Element (Nodal) Constraints FEMAP allows you to apply constraints directly to nodes or create constraint equations which provide a relationship between DOFs of nodes. There are three commands which apply constraints directly to the nodes: Nodal, Nodal on Face, and Equation. Each of these commands is discussed below.

4.3.9.1 Model, Constraint, Nodal... Nodal constraints are used to prevent movement in one or more nodal directions (degrees of freedom). Creating nodal constraints is a two step process: (1) select the nodes to be constrained using the standard entity selection dialog box, and (2) choose the degrees of freedom, or component directions, at each of these nodes, which will be constrained. The same constraints will be applied to all of the nodes that you select in a single command. Title: Allows you to enter a title for the “Constraint Definition” being created. If you do not enter a title, a default title will be created based on the type of constraint which was created. For example, if you create a constraint on a selected node or nodes, the default title will be “Constraint on Node”. Color/Palette and Layer: These controls define parameters for the nodal constraint to be created. Coordinate System: This list allows you to choose a coordinate system which will define the nodal degrees of freedom, and hence the constraint directions, for all selected nodes. You can also choose “-1..Use Nodal Output System” to use the coordinate system that was selected as the nodal output coordinate system (see Section 4.2.1, "Model, Node..."). If the coordinate system that you choose is different from your previous selection, you will be asked to confirm that you want to overwrite the previous selection for all selected nodes. Note: Be careful when you change the output coordinate system. If you have other constraints defined on the same node, even in other constraint sets, you are implicitly changing their orientation every time you change the output coordinate system. These changes can result in modeling errors which FEMAP can not detect. Remember, you can only have one output coordinate system per node. All constraints, in all sets, as well as everything else that references nodal degrees of freedom, are specified relative to that coordinate system.

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Specifying Degrees of Freedom Any combination of the six nodal degrees of freedom (TX, TY, TZ, RX, RY and RZ) can be selected using the check boxes. In many cases however, standard combinations of degrees of freedom will be needed. For these situations, you can quickly select the combination by pressing the appropriate command button. The following table shows the combinations which are available. In the table, * indicates a constrained degree of freedom. Command Button Fixed Free Pinned No Rotation X Symmetry Y Symmetry Z Symmetry X AntiSym Y AntiSym Z AntiSym

TX

TY

TZ

RX

RY

RZ

*

*

*

*

*

*

*

*

* *

* *

* * *

* * * * *

* * *

* * *

*

* * *

Simply choose the command button you need, followed by OK, to create the constraint.

Other Uses for Nodal Constraints In most cases, you will want to create nodal constraints to do exactly what their name implies - constrain your model. For some types of analysis (usually modal analysis) other sets of degrees of freedom can be used. One typical example of this is the analysis set (Nastran ASET, ANSYS M set, STARDYNE GUYAN set) which is often used for reduced modal analysis. FEMAP's translators support these additional, non-constraint sets. All you have to do is create an additional set, just like you specified your constraints, which contains the nodal degrees of freedom that you want. It is a good idea to specify a title that will help you to properly identify the set. Then when you translate your model, simply choose this set for its intended purpose, instead of translating it as a constraint set.

Quick Constraint Icons These icons create specific types of nodal constraint combinations on a selected set of nodes:

...Fixed - constrains all six degrees-of-freedom

...Pinned - constrains the three translational degrees-of-freedom

...No Rotation - constrains the three rotational degrees-of-freedom

4.3.9.2 Model, Constraint, Nodal on Face... ...works just like Model, Constraint, Nodal, but instead of directly selecting the nodes where constraints will be applied, you select elements and element faces. FEMAP then automatically finds all of the nodes on those faces and applies the specified constraints. For more information, see Section 4.3.3.3, "Model, Load, Nodal On Face...".

4.3.9.3 Model, Constraint, Equation... ...relates the motion or displacement of two or more (up to 70) nodal degrees of freedom. When you create a constraint equation, you must specify all of the terms in the following equation: 0 =

∑ Aj uj

where Aj are the equation coefficients, and uj are the nodal degrees of freedom

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Equation coefficients are directly specified in the constraint equation definition dialog box: Add, Multiple Nodes, Replace, Delete: Nodal degrees of freedom are identified by selecting a node number and selecting the degree of freedoms (see table below). To input one node at a time, define the coefficient, select the degrees of freedom, and then select/input the node and press Add. This will add it to the constraint equation. You can also add multiple nodes, if you have multiple nodes in the constraint equation that have identical degrees of freedoms and coefficient. Simply input the coefficient, select the degrees of freedom, and then press the Multiple Nodes button. You will then see the standard entity selection dialog box. Select the appropriate nodes and press OK. This will add these nodes with the selecting degrees of freedom and coefficient to the constraint equation. You can also modify your selections by highlighting a selection in the dialog box. When a selection is highlighted, you can remove it by pressing Delete, or change it to your current pick by pressing Replace. Number 1 2 3 4 5 6

DOF TX, X Translation TY, Y Translation TZ, Z Translation RX, X Rotation RY, Y Rotation RZ, Z Rotation

As always, the nodal degrees of freedom are in the X, Y and Z directions defined by the nodal output coordinate systems. ID, Color, Layer: In addition to the equation terms, you must define an equation ID. This ID must be unique within each constraint set, and is used only to identify the equation within FEMAP. The ID will automatically increment each time that you create a new equation. You can also specify a Color and Layer for each equation.

4.3.10 Geometric Constraints You may also create nodal constraints in FEMAP by constraining geometry. FEMAP will automatically transfer these constraints to nodes attached to the constrained geometry upon translation or expansion. There are two types of geometric constraints - standard and advanced. Standard geometric constraints only allow you to specify either all translations (DOF 123 - Pinned), all translations + all rotations (DOF 123456 - Fixed), or all rotations (DOF 456 - No Rotation). These combinations do not require setting or changing the nodal output coordinate systems during translation, and can therefore be defined in any number of constraint sets, in any combination. Advanced geometric constraints give you full control of the degrees of freedom to constrain, but require more care when you are specifying them. Since analysis programs only support one output coordinate system per node, it is possible to specify combinations of advanced geometric constraints that can not be solved in a single analysis. Geometric constraints are expanded to nodal constraints upon translation or expansion. If you have already defined nodal constraints for nodes on the geometry, FEMAP will combine the constraints. In this manner, you could pin nodes on a curve, and then create a no rotation condition on one of the nodes through Model, Constraint, Nodal, and the combined result would be a pinned surface with one node as fixed.

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The geometric constraints, similar to the geometric loads, are divided into four commands: On Point, On Curve, On Surface, and Expand. Whether you are defining constraints on points, curves or surfaces, you will see the same dialog box. The Standard constraint types are available at the top of the dialog box. The Advanced types are at the bottom of the box.

Advanced Constraints There are three available approaches to defining advanced geometric constraints. “Arbitrary in CSys” is available for points, curves and surfaces. “Surface” is available for all surface constraints. “Cylinder/Hole” is only available if you select one or more cylindrical surfaces. The first, “Arbitrary in CSys”, gives you full control over the six nodal degrees of freedom in any coordinate system you specify. You can either pick a coordinate system from the list, or choose “Use Nodal Output Sys”. If you pick a coordinate system, all nodes will have their output coordinate systems changed to that system, and the constraints will be applied. If you choose “Use Nodal Output Sys”, only the constraints will be applied - it is up to you to manually define the nodal output coordinate systems so that the degrees of freedom are properly interpreted. “Surface” constraints are intended to automatically select the degrees of freedom necessary to match certain physical conditions. In all of these cases, new coordinate systems will be created, as necessary, and assigned as nodal output coordinate systems, to create the selected conditions. “Sliding along Surface” will constrain the direction perpendicular to the surface, and if “Include Rotational DOF” is checked, the rotational degrees of freedom around the two axes that result in rotations out of the surface. “Move Normal to Surface” does just the opposite, constraining the in-surface translations and optionally the in-surface rotations. If you choose “Sliding in Specified Direction”, degrees of freedom normal to that direction will be constrained. In this case, you will also be asked to specify the sliding direction, which is used to align the resulting output coordinate systems. “Cylinder/Hole” is very much like “Surface”, except that they can only be applied to cylindrical surfaces. In this case the output coordinate system will be aligned with the axis of the cylinder/hole, and you can constrain any combination of the three directions.

Expanding Advanced Constraints Any time you expand advanced geometric constraints, the nodal output coordinate systems will be created and assigned. This will happen whether you use the Expand command, or simply translate the model for analysis. These output coordinate systems will not be removed if the expanded constraints are compressed. In the case of translation for analysis, the output coordinate systems are needed for proper interpretation of the analysis results. As stated before, some care must be taken when applying advanced geometric conditions. Because of the restriction in analysis programs of a single output coordinate system per node, there are many conditions that can not be represented in a single analysis. For example, lets assume that you wanted to analyze one condition that constrained some arbitrary set of DOF in a specified coordinate system (using “Arbitrary in CSys”), and you also wanted to analyze another condition that specified “Sliding in Surface”. Even if you defined two constraint sets, this will not in general be possible, since the output coordinate system specified for the first condition may not match the one required for the second. If you attempt to do this, FEMAP will do attempt to match the second condition as closely as possible to your request, but you should carefully check your model to see that it is what you want. To investigate this a little further, it is good to understand the process FEMAP uses to expand these constraints. FEMAP will first attempt to define the output coordinate systems for each node. Starting with the first constraint set required/selected, the required coordinate directions at the nodes will be defined. The process will

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continue until all coordinate directions at each node have been defined. This may allow proper matching of more than one constraint request - for example constraining sliding in surface, really only requires one direction be specified - the normal to the surface - both of the in-surface directions will be constrained, and can therefore be arbitrarily specified, as long as they are in-surface. This allows FEMAP to also properly handle another constraint request that might require a specific in-surface direction. Once the coordinate systems have been computed and assigned, then FEMAP will start the process of actually assigning constraints. At this time, the desired constraint directions are considered individually. If they match with the coordinate directions of the output coordinate system, as all should if they meet the “single output coordinate system” restriction, they are simply applied to the nodes. If multiple requests force the coordinate system to be improperly defined, then request will not precisely match the coordinate system - in this case every degree of freedom that is partially constrained will be fully constrained.

4.3.10.1 Model, Constraint, On Point... ...allows you to apply constraints directly to points, which are then transformed to nodal constraints upon translation or expansion. This command can ease the entity selection process since you will typically have many more nodes than points in your model, however, it is often just as easy to apply the constraints directly to the nodes with the Model, Constraint, Nodal command.

4.3.10.2 Model, Constraint, On Curve... ...allows you to apply constraints directly to curves. You simply select the curves through the standard entity selection box, and then select the type of constraint. Nodes attached to that curve will then be constrained upon translation or expansion.

4.3.10.3 Model, Constraint, On Surface... ...allows you to apply constraints directly to surfaces. You simply select the surfaces through the standard entity selection box, and then select the type of constraint. Nodes attached to that curve will then be constrained upon translation or expansion.

4.3.10.4 Model, Constraint, Expand... ...is used to expand or compress geometric constraints. It operates identically to Model, Load, Expand. You can select individual types to expand, or an entire set. You can also compress an entire set.

If you choose Convert to Nodal, the geometric constraint will be removed and be replaced by nodal constraints. Just like with the Model, Load, Expand command, be careful when converting to nodal. This conversion is permanent. You cannot go back to the original geometric load. . .

4.3.11 Constraint Set Manipulation This section contains command to copy or combine entire constraint sets.

4.3.11.1 Model, Constraint, Copy... ...duplicates the active constraint set. All nodal constraints and constraint equations are copied to the new set. If you do not want to duplicate all of them, use the Delete, Model, Constraint - Definition or Delete, Model, Constraint Individual commands to remove unwanted constraints from the new set.

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Input for this command is minimal. Simply specify the ID of the constraint set that you want to create. This new set must not already exist. FEMAP will create a duplicate copy of the active set with the ID that you specify. After the copy has been made, FEMAP will ask whether you want to activate the new set. Answer no if you want to continue working with the original constraint set. Answer yes to work with the new copy. Hint:

You may want to use the Model, Constraint, Create/Manage Set command to modify the title of the new copy. FEMAP will always create it with the same title as the original set that was copied.

4.3.11.2 Model, Constraint, Combine... ... enables you to combine two or more constraint sets into one new constraint set. This option works much like Model, Load, Combine, (See Section 4.3.6.2, "Model, Load, Combine...") except there is no scale factor input, and you have the option to Combine or Overwrite constraints for each set that you add to the Combinations list. A “+” in front of the Load Set name designates Combine, while an “O” designates Overwrite.

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4.4 Creating Connections and Regions The commands under the Connect menu are used to create connections usually by creating all of the different entities required to set up contact conditions. How these contact conditions are used depends on the selected options and the Finite Element solver being used to perform the analysis. There are basically three steps in creating contact for these programs. They involve three different entity creations: •

Connection Property



Connection Region



Connectors

This type of contact is currently supported for NX Nastran, ABAQUS, ANSYS, MARC, LS-DYNA, and NEi/Nastran. In most cases, the solver you are using determines which Connection Property will need to be used to create appropriate contact conditions. The top portion of the Connect menu aids in the creation of connections based entirely on geometry. FEMAP has a command to automatically determine which geometric bodies will come into contact with one another based on some factors and automatically generate the Connection Regions, Connection Properties, and Connectors. There is also a command which allows you to set-up contact conditions by choosing specific surfaces (or sets of surfaces) to use as Connection Regions, then selecting a Connection Property which is used to create a Connector between the Connection Regions. The middle portion of the Connect menu allows you to create each separate type of entity required to set up contact conditions. These commands allow you to use nodes, elements, or property information to generate Connection Regions, as well as geometry. Also, depending on your solver, curves can sometimes be used to create “analytical rigid surfaces” for use with axisymmetric models. Connection regions are usually geometry, element, or node-based regions for contact, but the same concept can be used to create regions for other types of analysis conditions. The bottom portion of the Connect menu may be used to create three specialized types of regions useful for Nastran users, Fluid Regions, Bolt Regions (used to apply a Bolt Pre-load in NX Nastran only), and Rotor Regions (used to define “rotors” for Rotor Dynamics in NX Nastran only) A Fluid Region allows you to create a region of elements to simulate either a finite volume “internal” fluid (i.e. a fluid in a contained area) or an infinite volume “external” fluid (i.e., ship floating in a body of water). The regions can be created in a similar manner to Connection Regions by using element IDs and face numbers OR elements associated to the positive or negative side of a surface. Along with defining the physical regions that can be affected by the fluid, there are additional options which can be set up for creating the MFLUID entry for the Nastran solver. A Bolt Region is used to create a region of elements where you would like to apply a bolt “preload”. The “preload” is a specified torque which has been translated into an axial load, arising from components in an assembly being bolted together. Each Bolt Region represents a “bolt” and there can be multiple “bolts” in a single model, all with unique “preloads”. When analyzing “preloaded bolts”, you may be interested in obtaining the stresses due to the preload condition alone or due to a combination of the bolt preload and additional loading conditions. A Rotor Region is used to create a region of nodes which you would like to specify as a “rotor” for Rotor Dynamics in NX Nastran. There are also options to set the rotation axis, damping values, and individual rotor load sets. FEMAP gives you the ability to “enable “and “disable” Fluid, Bolt, and Rotor Regions which can be very useful when trying different numbers of MFLUIDs, Bolt Preloads, and Rotors in different analysis runs.

4.4.1 Connect, Automatic... ...creates connections automatically based on the proximity of geometric entities selected in your model using a number of parameters. These parameters include specific values for Tolerance (distance between bodies) and Angle Tolerance, as well as choice of a “Detection Strategy” (Minimal to Aggressive) and options for the way multiple Connection Regions will be combined on the same solid.

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FEMAP will automatically create Connection Regions, a specific Connection Property (or use one that has already been defined), and Connectors between bodies which are within the tolerance values and fit the Detection Strategy criteria. If you would like to create these entities one at a time, please see Section 4.4.3, "Connect, Connection Property...", Section 4.4.4, "Connect, Connection Region...", and Section 4.4.5, "Connect, Connector... (Contact Pair)" Coincident Surface Detection Tolerance Essentially, the Tolerance value is a distance between bodies that FEMAP will use to determine if automatic connections should be generated between surfaces. The default value for Tolerance is set to be 5 times the default node merge tolerance in FEMAP. Note: FEMAP determines the default node merge tolerance based on overall model size. The number is 1/10000 of the “model box diagonal” (think of the model box being an invisible box that completely encapsulates every entity in the model). You can override the default node merge tolerance by specifying a value in Tools, Parameters. In some cases, you may need to change this value to have FEMAP detect more or less surfaces for auto-connection. Angle Tolerance The Angle Tolerance can be used to allow FEMAP to detect connections between surfaces on bodies which are not “planar” to one another. By default, FEMAP will only create contact between surfaces which are within 1 degree of being “planar” to one another. Many times you will only want to create contact conditions between the surfaces of bodies which are somewhat “planar” to one another. This is especially the case for setting up “Glued/Bonded” contact. Look For Two different types of connections can be created automatically in FEMAP, “Face-to-Face” connections (usually between multiple solids or “stacked” surfaces) and “Edge-to-Face” connections (usually between non-manifold junctions of multiple surfaces, i.e., a t-junction). This option specifies what type of connections the command should be looking for in the model. Choose to find Face-Face Only (default), All Connections, or Edge-Face Only. Note: Only certain FEA solvers support “Edge to Face” contact, so be sure to see if a particular solver supports “Edge to Face” contact. If not, be sure Look For is set to “1..Face-Face Only”. Detection Strategy FEMAP gives you 5 different options for Detection Strategy. Depending on the Detection Strategy you choose FEMAP will go from detecting a minimal amount of connections using a limited number of geometric entities to actually swelling bodies (internally, the geometry will not actually be changed in the model) and attempting to Boolean them together for the purpose of finding the maximum number of surfaces for use in creating connections. As you move from left to right, you are adding methods of detection. For example, if you are on Detection Strategy 2, FEMAP will actually perform Detection Strategy 1 and then Detection Strategy 2. If you are on Detection Strategy 5, Detection Strategies 1-4 will be attempted and then Detection Strategy 5. Here is a little more information on each option going from Left (Minimal) to Right (Aggressive) •

Analytical - Planes Only (Minimal) - FEMAP will only create connections between “planar” surfaces on bodies within the Tolerance and Angle Tolerance detection criteria.



Analytical - Cylinders, Spheres, Cones, and Toroids (Default) - In addition to creating connections between “planar” surfaces, FEMAP will also look for connections between sets of cylindrical, spherical, conical, and toroidal surfaces. This is the default setting for FEMAP and will often find the most appropriate surfaces for creating connections.

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Boolean - FEMAP will create Connections using adjacent surfaces on bodies which could be Booleaned together if you were using a command such as Geometry, Solid, Add... and are within the other criteria.



Swell, then Boolean - FEMAP will actually “swell” all of the selected solids by 1/2 the value specified in Tolerance and then attempt to Boolean the “swelled” solids together. If after swelling a Boolean can take place, Connections will be created between the surfaces on those bodies which fulfill the detection criteria.



Intermittent Swelling, then Boolean (Aggressive) - FEMAP will actually “swell” all of the selected solids by intermittent values based on the Tolerance value and then attempt to Boolean the “swelled” solids together after each iteration. If after swelling a Boolean can take place, Connections will be created between the surfaces on those bodies which fulfill the detection criteria.

Note: If you don’t know which settings to use for Automatic Detection, it is better to start with the default values for the Tolerance and Angle Tolerance and the “Minimal” Detection Strategy options. FEMAP will not overwrite any Connections or create duplicate Connections which have been created, so you can use larger Tolerance settings and more “Agressive” Detection Strategies to have FEMAP detect additional connections. Also, connections will not be created between surfaces linked with “Adjacent Surface Matching”. Check for Connections in same Solid When this option is on, FEMAP will search for surfaces on the same solid which fulfill the detection criteria and then create a connection between those surfaces. This can be helpful if you are performing an analysis on a part (often times a circular part) where the two ends will be “clamped” together or a rubber “boot” which may contact itself in many places as it is displaced. This option is off by default. Combine all Connections between Solids When this option is on, FEMAP will combine all Connection Regions it has created automatically on a single solid into a single Connection Region for that particular solid. This limits the number of Connection Regions which will be created in an assembly model containing a number of solids. This option is on by default but if you turn it off you will be able to see exactly which surfaces FEMAP is detecting to create Connection Regions and which sets of Connection Regions are being connected with Connectors automatically. Note: You may want to turn this option off when using the Check for Connection in same Solid option in order for FEMAP to create Connectors between surfaces on the same solid, which some analysis codes will require in order to create “self-contact” conditions on the same part.

Connection Property This portion of the of the Auto Detection Option for Connections dialog box allows you to create a new default Connection Property or choose an existing Connection Property to use when automatically creating connections. •

Contact - Creates a new Connection Property using “0..Contact” as the Type and will enter the same default values which are entered when the Defaults button is used in the Define Connection Property dialog box



Glued - Creates a new Connection Property using “1..Glued” as the Type and will enter the same default values which are entered when the Defaults button is used in the Define Connection Property dialog box



Property - Allows you to choose any previously created Connection Property from a from a drop-down list.

4.4.2 Connect, Surfaces... ...allows simple creation of a “connection” between two single surfaces, a set of surfaces and a single surface, or two sets of surfaces. Basically, it allows you to create 2 separate Connection Regions then a automatically creates a Connector between those Connection Regions using a specified Connection Property.

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Connect Surfaces • Master (Target) - Creates a new Connection Region using a selected surface or surfaces if Multiple has been chosen to be used as the “Master” in a Connector. •

Slave (Source) - Creates a new Connection Region using a selected surface or surfaces if Multiple has been chosen to be used as the “Slave” in a Connector.

Connection Property FEMAP allows you to choose an existing Connection Property to use when creating this connection. There is also an option to create a new Connection Property. Search for Related Surfaces When this option is turned on, FEMAP will search for “Related Surfaces” to also put into the Master or Slave Connection Region. A “Related Surface” is defined as a surface which was created from the same underlying geometry to the selected surface(s). This option is on by default. For example, if a cylindrical surface is split into two periodic faces by Parasolid (which is common), and one of the faces is selected for the Slave Connection Region, the other face would also be included in the Slave Connection Region when this option is turned on. Other examples include surfaces split using imprinted curve or surfaces separated by a Boolean operation such as Geometry, Solid, Remove. Extruded from boundary surface If either top surface is selected, there are no “related surfaces” Would NOT be “Related”

Primitive with Boolean cut-out If either top surface is selected, there are “related surfaces” Would be “Related”

4.4.3 Connect, Connection Property... Connection Properties You must define interface information for the Connector with a Connection Property. When you define a Connection Property, you will see the Define Connection Property dialog box for contact pairs. The typical entity information contained in FEMAP: ID, Color, Layer and Title are available for the Connection Property. It is important to give each Connection Property a descriptive title so you may easily select one from the drop-down property list when defining a Connector. Connect Type is a specialized entry for the Connection Property and allows you to choose between 0..Contact and 1..Glued. When Connect Type is 0..Contact, almost all contact options are available for all solvers. When Connect Type is set to 1..Glued, only the options required to create “Glued” or “Bonded” contact are available. Note: Connect Type has no effect on the MARC, DYNA, or NEi Nastran tabs. Also common to the Define Connection Property dialog box, regardless of what “Tab” is chosen, are the Defaults, Load, Save, and Copy buttons. Clicking the Defaults button will insert a different set of “Default values” on each tab. These are recommended values for each solver and/or type of analysis and FEMAP fills them in on all tabs at once. Load is used to load a saved Connection Property from the Connection Property Library (conprop.esp file, usually located in the FEMAP directory) and Save is used to store a new or modified Connection Property in that same library. A Title is required in order to save the a Connection Property to the Connection Property Library and all

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values on all tabs will be stored together. For more information on libraries, see Section 2.6.2.8, "Library/Startup" and Section 4.3.6, "Library Selection" of the FEMAP User’s Guide. Copy allows you to copy the values from an existing Connection Property in your model to a new Connection Property. You must have a least one Connection Property in your model for Copy to be available.

The rest of the dialog box is separated into 8 tabs. Each tab has the required input for a particular solver and/or analysis type. The first 3 tabs are used for creating contact conditions for different solution sequences in NX Nastran. NX Linear (SOLs 101, 103, 111, and 112 for “Linear Contact”, all solution sequences except SOLs 144-146, 601, and 701 for “Glued Contact”), NX Advanced Nonlinear (SOL 601), and NX Explicit (SOL 701) each have a tab containing different options associated with a particular analysis type. Each of the other 5 tabs contain options required to set up contact conditions for a particular solver. Each tab creates program specific input for one of the following solvers: ABAQUS, ANSYS, MARC, LS-DYNA, or NEi/Nastran. The options available for each solver are discussed in greater detail below Note: FEMAP will use the information you have set on the Interfaces tab of the Preferences dialog box to set which tab of the Define Connection Property dialog box should be “active” by default. For example, if you have your Interface set to “16..ABAQUS”, when you use the Connect, Connection Property command, the “ABAQUS tab” will be “active” until you select a different tab. If you were to then change your Interface to “45..NX Nastran” and your Analysis Type to “22..Advanced Nonlinear Static”, the “NX Adv Nonlin tab” would be “active” until changed.

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4.4.3.1 NX Nastran Linear and Glued Contact Properties (NX Linear tab) The linear contact property for NX Nastran contains options for linear contact which is available in Linear Statics (SOL 101), Modal Analysis (SOL 103), Modal Frequency Response (SOL 111), and Modal Transient Response (SOL 112). It also contains options for “Glued Contact”, which is available in all NX Nastran solution sequences except SOL 144-146 (Aeroelasticity) and SOL 701 (Explicit Transient Dynamics). The glued option for SOL 601 can be found on the NX Adv Nonlin tab. These options can be reached by pressing the NX Linear tab in the Define Connection Property dialog box.

Contact Pair (BCTSET) The options in this portion of the dialog box can be set individually for each Connector (contact pair) that is created in the model. These options will be written out to the BCTSET entry for each individual contact pair. Each contact pair will be designated in the graphics window with a single line going from one Connection Region to another and this line is a contact element. Friction - Enters a value in the FRICi field on the BCTSET entry. Designates the Static Coefficient of friction for contact pair “i”. Note: In general, if different friction values are NOT needed then the contact pairs should all reference the same contact property.

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Min Contact Search Dist - Enters a value in the MINDi field on the BCTSET entry. Designates the Minimum search distance for contact pair “i”. Note: The minimum distance can be negative and used for an interference fit condition modeled as overlapping surfaces. Max Contact Search Dist - Enters a value in the MAXDi field on the BCTSET entry. Designates the Maximum search distance for contact pair “i”. Note: The max distance must be defined for all contact problems. This is the distance that NX Nastran will search for contact from the element normal. Contact Property (BCTPARM) These options need to only be defined once for a contact analysis, regardless of how many Connectors (contact pairs) are defined in the model. Each Connector has an ID assigned to it and can reference a different Connection Property. FEMAP will use the Connection Property referenced by the Connector with the lowest ID to define the BCTPARM entry for the entire model. For example, if a model has 2 Connectors (contact pairs) with ID numbers 101 and 102, the Connection Property values defined in the property associated with Connector ID 101 would be used for the analysis. Max Force Iterations - Creates the MAXF field on the BCTPARM entry. Designates the maximum number of iterations for a force (inner) loop (Default = 10). Max Status Iterations - Creates the MAXS field on the BCTPARM entry. Designates the maximum number of iterations for a status (outer) loop (Default = 20). Force Convergence Tol - Creates the CTOL field on the BCTPARM entry. Designates the Contact Force convergence tolerance (Default = 0.01). Convergence Criteria and Num For Convergence - Together, these two values create the NCHG field on the BCTPARM entry. The value and type of number (real or integer) entered for Num For Convergence depends on the option set for Convergence Criteria: •

0..Number of Changes - When this option is set, Num for Convergence must be an integer > 1. This value defines the allowable number of contact changes.



1..Percentage of Active - When this option is set, Num for Convergence must be entered as a percentage (between 1 and 99, which will appear as 0.01 to 0.99 in the NX Nastran input file). The solver treats this value as a percentage of the number of active contact elements in each outer loop of the contact algorithm. The number of active contact elements is evaluated at each outer loop iteration.

Min Contact Percentage - Creates the MPER field on the BCTPARM entry. Designates the Minimum Contact Set Percentage (Default = 100). Initial Penetration - Creates the INIPENE field on the BCTPARM entry. Controls how Nastran handles initial gap or penetration of the generated contact elements (Default = 0). •

0..Calculated - Use the value calculated from the grid coordinates. In the case of penetrations, a model may experience “press fit” behavior when using this option.



2..Calculated/Zero Penetrations - Same as 0..Calculated, but if penetration is detected, set the value to zero.



3..Zero Gap/Penetration - Sets the penetration/gap to zero for all contact elements.

Shell Offset - Creates the SHLTHK field on the BCTPARM entry. Shell Thickness Offset flag. (Default = 0) •

0..Include shell thickness - Include half shell thickness as surface offset.



1..Do not include thickness - Does not include thickness offset.

Avg Methods - Creates the AVGSTS field on the BCTPARM entry. Determines the averaging method for contact pressure/traction results (Default = 0). •

0..Include All Elements - The averaging of Pressure/Traction values for a contact grid will include the results from ALL contact elements attached to the grid regardless of whether they are active or inactive in the contact problem

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1..Include Active Elements - The averaging of the Pressure/Traction values for a contact grid will exclude those contact elements which are not active in the contact solution and thus have a zero Pressure/Traction value.

Contact Status - Creates the RESET field on the BCTPARM entry. Flag to indicate if the contact status for a specific subcase is to start from the final status of the previous subcase. (Default =0) •

0..Start from Prev Subcase - Starts from previous subcase.



1..Start from Init State- Starts from initial state.

Contact Inactive - Creates the CSTRAT field on the BCTPARM entry. When set to “1..Restrict From Inactive”, prevents all of the contact elements from becoming inactive. •

0..Can Be Inactive (Default) - All contact elements can become inactive



1..Restrict From Inactive - Solver will reduce the likelihood of all of the contact elements becoming inactive.

Note: Under certain conditions, all of the contact elements could become inactive which may lead to singularities. Setting the parameter to “1..Restrict From Inactive” will reduce the possibility of this happening. Shell Z-Offset - Allows you to choose if the Z-Offset on shell elements should be included in determining “Glued Contact.” Creates ZOFFSET field in BGPARM entry and gives you 2 choices for the corresponding Value field: •

0..Include Z-Offset (Default) - Z offset of shells is included for determining glued surfaces.



1..No not Include Z-Offset - Z offset of shells is NOT included for determining glued surfaces.

Note: The Defaults button will automatically fill in the dialog box with the default values suggested by NX Nastran. It may be helpful to try and run the analysis with the defaults and then run it again if any modifications are needed to create more accurate results or achieve convergence. Adaptive Stiffness - This is a flag to indicate whether adaptive stiffness is activated. Creates PENADAPT field on BCTPARM entry (Default=0). When not checked, it places a “0” (No Adaptive adjustment) into the PENADAPT field, when checked places a “1” (Adaptivity adjusts contact stiffness) into the PENADAPT field. Penetration Factor - Creates the PENETFAC field on the BCTPARM entry (Default = 1.0E-4). Designates the penetration factor for adaptive penalty stiffness adjustment. Only used when Adaptive Stiffness is “on” and should usually only be set to a lower value to reduce the amount of penetration allowed to occur in an analysis. Common Contact (BCTPARM) and Glue (BGPARM) Parameters This section contains options for Glued contact and several options available for both Glued Contact and Linear Contact. Glue Type - Creates the GLUETYPE field on the BGPARM entry. Specifies the glue formulation. •

1..Spring - Normal and tangential springs will be used to define connections. May use the Auto Penalty Factor or a combination of values for Normal Factor and Tangential Factor.



2..Weld (Default) - A “weld like” connection will be used to define the connections. Only uses the Glue Factor.

Eval Order - Determines the number of “Linear Contact or Glue Points” for a single element on the source region. Creates INTORD field in BCTPARM or BGPARM entry and gives you 4 choices: •

0..Default - Does NOT write the INTORD field or corresponding value field to the BCTPARM or BGPARM entry. Simply uses the default value for “Linear” or “Glued” contact built into the NX Nastran solver.



1..Low - Lowest order of points on source region.



2..Medium - Medium order of points on source region. This is the default.



3..High - Highest order of points on source region.

The higher the integration order, the longer the solve will take. Refine Source - Determines if the source region is refined for the “Linear” or “Glued” Contact solution. Creates REFINE field on the BCTPARM or BGPARM entry and gives you 2 choices for the corresponding Value field: •

0..Do Not Refine - Does not refine the “Linear Contact/Glue” source region based on target surface definition.

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1..Refine Source to Target (Default) - Refines the “Linear Contact/Glue” source region based on target surface definition.



2..NXN 7.0 Method - Refines the “Linear Contact/Glue” source region using the NX Nastran 7.0 method.

Penalty Factor Units - Creates the PENTYP field on the BCTPARM or BGPARM entry. Specifies how contact element stiffness is calculated. When setting penalty factors for linear contact or glued contact when Glue Type = 1..Spring (GLUETYPE=1) •

1..1/Length (Default) - Normal Penalty Factor (PENN) and Tangential Penalty Factor (PENT) are entered in units of 1/Length.



2..Force/(Length x Area) - Normal Penalty Factor (PENN) and Tangential Penalty Factor (PENT) are entered in units of Force/(Length x Area).

When setting penalty factors for glued contact when Glue Type = 2..Weld (GLUETYPE=2) •

1..Scale Factor - Glue Factor (PENGLUE) is a unitless value.



2..F/L^2 - Glue Factor (PENGLUE) has the units of F/Length squared.

Auto Penalty Factor - This is a flag to indicate whether normal and tangential penalty factors will be automatically calculated. When this box is checked in FEMAP, no special field will be written to the BCTPARM. This is the default for NX Nastran. Normal Factor - Creates the PENN field on the BCTPARM or BGPARM entry. Designates the penalty factor for the normal direction (Default = 10.0 for BCTPARM, 100 for BGPARM). Tangential Factor - Creates the PENT field on the BCTPARM or BGPARM entry. Designates the penalty factor for the tangential direction (Default = 1.0 for BCTPARM, 100 for BGPARM). Glue Factor - Creates the PENGLUE field on the BGPARM entry (Default = 100). Designates the penalty factor when Glue Type is set to 2..Weld (GLUETYPE=2). Note: Glued contact works differently in NX Nastran SOL 153 than any other solution sequence. Only GLUETYPE=1 may be used. Please see the NX Nastran Quick Reference Guide for more information. Glued Contact Property (BGSET) A brief description of Glued Contact: An option to “Glue” elements together during a solution is available in NX Nastran version 4.1 and above. Glue definitions can be used in all solution sequences except SOL 144-146 (Aeroelasticity) and SOL 701 (Explicit Transient Dynamics). The “Glue” option creates stiff springs or a “weld like” connection to connect pre-defined Connection Regions and prevents relative motion in all directions (these springs and “weld like” connections are essentially “glue elements”). “Glue elements” are created from the “free face” of one Connection Region to another if the regions are within the specified separation distance (Search Distance) for gluing to occur. Many different glued connections can occur in the same model and all of the connections will be placed in the same “Glue Set” (BGSET entry) in the NX Nastran input deck. Note: In Linear Statics (SOL 101), both Glued Contact AND Linear Contact can be defined in the same subcase. Also, the Glued Contact must be set up in the first subcase for all solutions sequences except in SOL 101, when Linear Contact is defined. In this case, Glued Contact can be defined in any subcase. Note: Glued contact is currently NOT available when using the Element Iterative solver in NX Nastran. Search Distance - Enters a value in the SDISTi field on the BGSET entry. Designates the Search Distance for the contact pair “i”. Essentially, this is telling NX Nastran that if the Connection Regions of the Connector (contact pair) are within this distance, which they should be, then Glued contact will be active for this contact pair. Note: By setting the value of search distance to a value larger than the largest distance between connection regions using Glued Contact, only one Glued Contact property is needed per model. Even if you have several different properties created for Glued Contact, FEMAP will automatically combine them all in to one BGSET entry in NX Nastran.

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4.4.3.2 NX Nastran Contact Property Options - Advanced Nonlinear Analysis (NX Adv Nonlin tab) For NX Nastran Solution 601, more than 1 Connector (contact pair) can be defined and each pair can have a different Connection Property. For each Connection Region, ALL of the values defined on the NX Adv Nonlin tab of the Define Connection Property dialog box are used for each respective Connector (contact pair).

Advanced Nonlinear Analysis has two NXSTRAT solver parameter dialog boxes in the Analysis Case Manager. For more information, see Section 8.7.1.23, "Advanced Nonlinear Analysis (NX Nastran Only)". Glued Contact Property (BGSET) Extension Factor - Enters a value in the EXTi field specified on the BGSET entry for the contact pair “i”. Specifies an “extension factor” for the target region. The “extension value” sent to the solver is calculated by multiplying the Extension Factor (EXTi) by the largest element edge in the source and target region. (Value must be between 0.0 and 0.25, Default = 0.01) General Contact Type - Lets you choose the contact algorithm type and writes the TYPE field on the BCTPARA entry. You get to choose between 0..Constraint Function, 1..Segment Method, or 2..Rigid Target. Depending on the contact algorithm, some portion of the dialog box will be available, while other portions are “grayed out”. Double Sided (check box) - This is a flag for single or double-sided contact. Creates NSIDE field on BCTPARA entry. When not checked, it places a 1 (Single-sided contact) into the NSIDE field, when checked places a 2 (Double-sided contact) into the NSIDE field.

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Initial Penetration - Flags how initial penetrations are handled. Writes the Initial penetration option to the INIPENE field on the BCTPARA entry. You can choose between: •

0..Eliminate - Initial penetrations are eliminated



1..Eliminate/Print - Initial penetrations are eliminated and the list of penetrating nodes is printed



2..Ignored - Initial penetrations are ignored. In successive steps, each contractor node is allowed to penetrate the target up to its initial penetration



3..Specify with Gap Distance - Initial penetrations or gaps are overridden by specified Gap Distance. This option is not available for rigid target algorithm

Gap Distance - Specifies a constant gap distance (GAPVAL) between the source region (contactor) and the target region when The Initial Penetration option is set to “3..Specify with Gap Distance”. A Negative Gap Distance means initial penetrations which will be eliminated. Penetration Depth - Penetration Depth for single-sided contact (NSIDE=1). Write PDEPTH field on BCTPARA entry. If PDEPTH > 0.0, then Penetration is detected when penetration is less than or equal to PDEPTH, and if Penetration > PDEPTH, penetration is deemed not to occur. Segment Normal - Indicates whether a continuous (interpolated) contact segment normal is used for the contact surfaces. Creates the SEGNORM field on the BCTPARA entry. You can choose: •

0..Default - SEGNORM = 1 if NSIDE = 1, SEGNORM = -1 if NSIDE = 2



1..Used - Continuous segment is used



-1..Not Used - Continuous segment is not used

Offset Type - Type of offset for contact regions. Creates the OFFTYPE field on the BCTPARA entry. Choose from: •

0..Single Sided - Use specified offset of NSIDE=1, use offset value of 0.001 for NSIDE=2



1..Single/Double-Sided - Use specified offset for NSIDE=1 or NSIDE=2



2..Half Shell Thick - Half the shell thickness is used for contact regions on shell elements and no offset for is used otherwise

Note: OFFTYPE = 2 can only be used with rigid target algorithm (TYPE=2). Offset Distance - Default offset distance value for contact regions. Creates OFFSET field on BCTPARA entry. Note: For TYPE=0 or TYPE=1, individual offset distances can be specified for each contact region using the BCRPARA entry to override the default offset distance specified here Birth Time - Birth time for contact set. Creates TBIRTH field on BCTPARA entry (default = 0.0). Death Time - Death time for contact set. Creates TDEATH field on BCTPARA entry (default = 0.0). If TDEATH is less than or equal to TBIRTH, it is ignored. Constraint Function Contact Algorithm (Contact Type = 0..Constraint Function only) Normal Constraint - Parameter for normal constraint function, “w”. Creates EPSN field on BCTPARA entry (Default = 1.0E-12). Frictional Constraint - Parameter for frictional constraint function, “v”. Creates EPST field on BCTPARA entry (Default = 0.001, must be greater than 0). Compliance Factor - Compliance Factor. Creates CFACTOR1 field on BCTPARA entry. (Default = 0.0). For more information about using contact with NX Nastran Solution 601, see Nonlinear Analysis Theory and Modeling Guide. Standard Contact Algorithm (Contact Type = 0..Constraint Function or 1..Segment Method) Disp Formulation - Selects the displacement formulation used for this contact set. Creates the DISP field on the BCTPARA entry. Choose from: •

0..Use NXSTRAT CTDISP - Use the formulation selected by CTDISP in NXSTRAT entry (Default)

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1..Small Disp Formulation - Use small displacement formulation (contact conditions are not updated)



2..Large Disp Formulation - Use large displacement formulation (contact conditions are updated)

Consistent Stiffness (check box) - This is a flag to indicate whether consistent contact stiffness is used. Creates CSTIFF field on BCTPARA entry (Default=0). When not checked, it places a 0 (Consistent contact stiffness is not used) into the CSTIFF field, when checked places a 1 (Consistent contact stiffness is used) into the CSTIFF field. Tied Tolerance (check box and field) - The check box is a flag to indicate whether contact regions in each contact pair are tied together. Creates TIED field on BCTPARA entry (Default=0). When not checked, it places a 0 (Not tied) into the TIED field, when checked, places a 1 (Tied) into the TIED field. The field is the actual Tied Tolerance value used to determine whether contactor nodes are tied to the target region when TIED=1 is specified. A contactor node is tied to its target region if the distance between them is less than or equal to TIEDTOL. Creates the TIEDTOL field on the BCTPARA entry. (Default=0.0) Note: Currently, the tied contact option assumes small rotations of the contact regions. Init Penetration Duration - Time to eliminate initial penetrations (Must be greater than of equal to 0.0, default =0). Creates TZPENE field on BCTPARA entry. If TZPENE=0.0, and INIPENE=0 or 1, then the initial penetrations are eliminated in the first time step. This may cause convergence difficulties for certain problems. By using TZPENE > 0.0, the initial penetrations are eliminated gradually over time TZPENE. Surface Extension Factor - Factor for extending contact surfaces beyond their boundaries. The amount of extension is given by this factor multiplied by the length of the contact segments. Creates EXTFAC field on BCTPARA entry. (Values must range from 1.0E-6 to 0.1; Default = 0.001) Friction Model - Allows you to choose the type of friction model using a drop down menu. Creates an integer from 0 to 13 (except 10 and 11) in the FRICMOD field on the BCTPARA entry to indicate which friction type is to be used. You can choose from the following friction types: •

0..Default (Param 1) - Constant coefficient of friction specified for each contact pair (FRICi field(s) on BCTSET entry).



1..Constant (Param1) - Constant coefficient of friction specified by FPARA1 (FPARAi refer to Friction Parameter 1-5 below).



12..Modified Model 1(1,2) - Modified Friction Model 1; uses FPARA1 and FPARA2.



13..Modified Model 2(1,2,3) - Modified Friction Model 2; uses FPARA1, FPARA2, and FPARA3.



2..Model 1 (1,2) - Friction Model 1; uses FPARA1 and FPARA2.



3..Model 2 (1,2,3) - Friction Model 2; uses FPARA1, FPARA2, and FPARA3.



4..Static/Dynamic (1,2,3) - Use different static and dynamic friction coefficients; uses FPARA1, FPARA2, and FPARA3.



5..vs Sliding Velocity (1,2,3) - Friction coefficient varies with sliding velocity; uses FPARA1, FPARA2, and FPARA3.



6..Anisotropic (1-5) - Anisotropic friction model; uses FPARA1, FPARA2, FPARA3, FPARA4, and FPARA5.



7..vs Contact Force (1,2) - Friction coefficient varies with consistent contact force; uses FPARA1 and FPARA2.



8..vs Time (1,2,3) - Friction coefficient varies with time; uses FPARA1, FPARA2, and FPARA3.



9..vs Coordinate (1-5) - Friction coefficient varies with coordinate values; uses FPARA1, FPARA2, FPARA3, FPARA4, and FPARA5.

Friction Param 1 - Friction parameter A1. Creates FPARA1 field on BCTPARA entry. Friction Param 2 - Friction parameter A2. Creates FPARA2 field on BCTPARA entry Friction Param 3 - Friction parameter A3. Creates FPARA3 field on BCTPARA entry Friction Param 4 - Friction parameter A4. Creates FPARA4 field on BCTPARA entry

NX Nastran Contact Property Options - Advanced Nonlinear Analysis (NX Adv Nonlin tab)

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Friction Param 5 - Friction parameter A5. Creates FPARA5 field on BCTPARA entry Friction Delay - Creates FRICDLY field on BCTPARA entry. When “checked”, FEMAP will specify a “1” in the value field for the corresponding FRICDLY field. This indicates that the application of friction will be “delayed”, meaning friction is applied on a node one time step after the node comes into contact. The “delay” of friction may improve convergence of the solution. (Default = 0...unchecked in FEMAP). Rigid Target Options (Contact Type = 2..Rigid Target only) This Contact Type is not applicable for 2D contact. You should only enter values in either the Current Algorithm section or Old Algorithm section, not both.

Note:

If you are using the values in the Old Algorithm (RTALG=1 on NXSTRAT) section, you will need to also check the Use Old Rigid Target Algorithm box in the NXSTRAT Iteration and Convergence Parameters dialog box of the Analysis Set Manager (see Section 4.10, "Preparing for Analysis").

Common Options Normal Modulus - Normal contact Modulus. Creates NCMOD field on BCTPARA entry (Default=1.0E11) Current Algorithm (RTALG=0 on NXSTRAT) Max Tensile Contact Force - Maximum tensile contact force allowed for a converged solution. Creates TFORCE field on the BCTPARA entry. Value must be greater than or equal to 0.0 (Default=0.001) Max Sliding Velocity - Maximum sliding velocity used in modeling sticking friction. If velocity is less than this value, sticking is assumed. If the velocity is higher, sliding is assumed. Creates SLIDVEL field on BCTPARA entry (Default=1.0E-10) Oscillation Check - Specifies whether oscillation checking is performed and when it is done. Creates OCHECK field on BCTPARA entry. This value must be an integer greater than zero (Default=5). When set to 0, oscillation checking will not be performed, otherwise oscillation checking will be performed after each “OCHECK value” equilibrium iteration. For example, if set to 3, oscillation checking will occur after every third iteration. Contact Gap - Contact is detected when the distance between the target and contactor (accounting for any offsets) is less than this value. Creates GAPBIAS field on BCTPARA entry (Default=0.0) Offset Method - Selects the method used for the implementation of offsets. Creates OFFDET field on BCTPARA entry. (Default=0.0) •

0..Default - NX Nastran chooses the implementation based on the shape of the target surfaces.



1..Sphere - Creates a sphere with a radius equal to the offset around each connector node on the source. Contact is detected between the sphere and the target surface.



2..Surface - Two surfaces are constructed for each source surface (an upper and a lower surface). The surfaces are constructed using the offsets and the averaged source normals. Contact occurs between points on the “constructed surfaces” and the target surface.

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Old Algorithm (RTALG=1 on NXSTRAT) Penetration Tolerance - Penetration Tolerance which gives the maximum penetration allowed into a rigid target surface. Creates PENETOL field on the BCTPARA entry. (Default=1.0E-8) Tangential Modulus - Tangential contact Modulus. Creates TCMOD field on BCTPARA entry (Default=0.0) Min Tensile Freeing Force - Minimum tensile contact force required to change the state of a contact node from “node in contact” to “free node”. Creates RFORCE field on BCTPARA entry. For instance, if the normal tensile force is greater than RFORCE, a node in contact becomes a “free node”. (Default=0.001) Max Total Freeing Force - Limit (Maximum) for the sum of all contact forces for nodes changing from the stat of “node in contact” to “free node”. Creates LFORCE field on BCTPARA entry. If the absolute value of the sum of the forces is larger than LFORCE, then automatic time stepping (ATS) method will be activated to subdivide the current time step into smaller time increments (Default = 1.0) Penetration Cutback and Max Penetration - Specifies whether penetration will be checked against the specified maximum allowable penetration. Creates RTPCHECK field (Default=0) and RTPMAX field (Default=0.001) on BCTPARA entry. •

0..No Checking - Penetration is not checked. This creates the possibility that the rigid target surface may penetrate the source excessively



1..Max Pen*Model Length - Penetration is checked and subdivision of the time step occurs if the penetration exceeds the value specified in the Max Penetration * the maximum model length.



2..Max Penetration - Penetration is checked and subdivision of the time step occurs if the penetration exceeds the value specified in the Max Penetration.

For more information about using contact with NX Nastran Solution 601, see Nonlinear Analysis Theory and Modeling guide.

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4.4.3.3 NX Nastran Contact Property Options - Explicit Transient Dynamics (NX Explicit tab) General For NX Nastran Solution 701, more than 1 Connector (contact pair) can be defined and each pair can have a different Connection Property. Like solution 601, ALL of the values defined on the NX Explicit tab of the Define Connection Property dialog box are used for each respective contact pair.

Note:

Advanced Nonlinear Explicit has a NXSTRAT solver parameter dialog in the Analysis Case Manager. For more information, see Section 8.7.1.24, "Advanced Nonlinear Explicit (NX Nastran Only)".

Contact Type - Lets you choose the contact algorithm type and writes the XTYPE field on the BCTPARA entry. You get to choose between 0..Constraint Function, 1..Penalty Method, or 3..Rigid Target. Depending on the contact algorithm, some portion of the dialog box will be available, while other portions are “grayed out” Double Sided (check box) - This is a flag for single or double-sided contact. Creates NSIDE field on BCTPARA entry. When not checked, it places a 1 (Single-sided contact) into the NSIDE field, when checked places a 2 (Double-sided contact) into the NSIDE field. Initial Penetration - Flags how initial penetrations are handled. Writes the Initial penetration option to the INIPENE field on the BCTPARA entry. You can choose between 0..Eliminate (Initial penetrations are eliminated), 1..Eliminate/Print (Initial penetrations are eliminated and the list of penetrating nodes is printed), or 2..Ignored (Initial penetrations are ignored. In successive steps, each contractor node is allowed to penetrate the target up to its initial penetration).

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Penetration Depth - Penetration Depth for single-sided contact (NSIDE=1). Write PDEPTH field on BCTPARA entry. If PDEPTH > 0.0, then Penetration is detected when penetration is less than or equal to PDEPTH, and if Penetration > PDEPTH, penetration is deemed not to occur. Segment Normal - Indicates whether a continuous (interpolated) contact segment normal is used for the contact surfaces. Creates the SEGNORM field on the BCTPARA entry. You can choose 0..Default (SEGNORM = 1 if NSIDE = 1, SEGNORM = -1 if NSIDE = 2), 1..Used (Continuous segment is used), or -1..Not Used (Continuous segment is not used) Offset Type - Type of offset for contact regions. Creates the OFFTYPE field on the BCTPARA entry. Choose from 0..Single Sided (Use specified offset of NSIDE=1, use offset value of 0.001 for NSIDE=2), 1..Single/Double-Sided (Use specified offset for NSIDE=1 or NSIDE=2), or 2..Half Shell Thick (Half the shell thickness is used for contact regions on shell elements and no offset for is used otherwise). Note: OFFTYPE = 2 can only be used with rigid target algorithm (TYPE=2). Offset Distance - Default offset distance value for contact regions. Creates OFFSET field on BCTPARA entry. Note: For TYPE=0 or TYPE=1, individual offset distances can be specified for each contact region using the BCRPARA entry to override the default offset distance specified here Friction - Static coefficient of friction for contact pair “i”. Creates FRICi field on BCTSET entry. Time Activation Birth Time - Birth time for contact set. Creates TBIRTH field on BCTPARA entry (default = 0.0). Death Time - Death time for contact set. Creates TDEATH field on BCTPARA entry (default = 0.0). If TDEATH is less than or equal to TBIRTH, it is ignored. Standard Contact Algorithm (Contact Type = 0..Constraint Function or 1..Penalty Method) Surface Extension Factor - Factor for extending contact surfaces beyond their boundaries. The amount of extension is given by this factor multiplied by the length of the contact segments. Creates EXTFAC field on BCTPARA entry. (Values must range from 1.0E-6 to 0.1; Default = 0.001) Init Penetration Duration - Time to eliminate initial penetrations. Creates TZPENE field on BCTPARA entry. (Default = 0.0) Note: If there is no duration for initial penetration (TZPENE = 0.0) and Initial Penetration (INIPENE) is set to 0 or 1, then the initial penetrations are eliminated in the first time step. This may cause convergence difficulties for certain problems. By using TZPENE > 0.0, the initial penetrations are eliminated gradually over time TZPENE. Penalty Contact Algorithm (Contact Type = 1..Penalty Method only) Penalty Stiffness Criteria - This drop-down menu selects the criterion for evaluation of normal penalty stiffness. Creates the XKNCRIT field on BCTPARA entry. There are 2 choices: •

0..Program Calculated - NX Nastran calculates the normal penalty stiffness.



1..User Defined - User specifies the normal penalty stiffness (XKN).

Normal Stiffness - Creates the XKN field on the BCTPARA entry. Specifies the normal penalty stiffness when 1..User Defined is specified for Penalty Stiffness Criteria (XKNCRIT = 1) Tangential Stiff Criteria - This drop-down menu selects the criterion for evaluation of tangential penalty stiffness. Creates the XKTCRIT field on BCTPARA entry. There are 2 choices: •

0..Program Calculated - NX Nastran calculates the tangential penalty stiffness.



1..User Defined - User specifies the tangential penalty stiffness (XKT).

Tangential Stiffness - Creates the XKN field on the BCTPARA entry. Specifies the tangential penalty stiffness when 1..User Defined is specified for Tangential Stiff Criteria (XKTCRIT = 1)

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Damp Coefficient Method - This drop-down menu selects whether damping will be used and whether or not the damping used will be a factor or critical damping. Creates the XDAMP field on the BCTPARA entry. There are 3 choices: •

0..Not Used - Damping is not used. Damping Coefficient (XNDAMP) is ignored.



1..As Crit Damping Factor - Damping is used and is a factor of the critical damping (i.e., the damping coefficient, specified in XNDAMP, is multiplied by the critical damping). This is the recommended choice if damping is used.



2..Directly Defined - Damping is used and the Damping Coefficient (XNDAMP) is specified directly.

Damping Coefficient - Specifies the relative or absolute damping coefficient (for normal penalty stiffness) when the penalty explicit contact algorithm is used and the Damp Coefficient Method is 1..As Crit Damping Factor or 2..Directly Defined (XDAMP = 1 or 2). Old Rigid Contact Algorithm (Contact Type = 3..Rigid Target only) Note:

If you are using the values in the Old Rigid Contact Algorithm section, you will need to also check the Use Old Rigid Target Algorithm box in the Contact Control portion of the NXSTRAT Solver Parameters dialog box of the Analysis Set Manager (see Section 4.10, "Preparing for Analysis").

Penetration Tolerance - Penetration tolerance which gives the maximum penetration allowed into a rigid target surface. Creates PENETOL field on BCTPARA entry (Default = 1.0E-8). Tangential Modulus - Tangential contact modulus. Creates TCMOD field on BCTPARA entry (default = 0.0). Current Rigid Contact Algorithm (Contact Type = 3..Rigid Target only) Max Sliding Velocity - Maximum sliding velocity used in modeling sticking friction. If velocity is less than this value, sticking is assumed. If the velocity is higher, sliding is assumed. Creates SLIDVEL field on BCTPARA entry (Default=1.0E-10) Contact Gap - Contact is detected when the distance between the target and contactor (accounting for any offsets) is less than this value. Creates GAPBIAS field on BCTPARA entry (Default=0.0) Offset Method - Selects the method used for the implementation of offsets. Creates OFFDET field on BCTPARA entry. (Default=0.0) •

0..Default - NX Nastran chooses the implementation based on the shape of the target surfaces.



1..Sphere - Creates a sphere with a radius equal to the offset around each connector node on the source. Contact is detected between the sphere and the target surface.



2..Surface - Two surfaces are constructed for each source surface (an upper and a lower surface). The surfaces are constructed using the offsets and the averaged source normals. Contact occurs between points on the “constructed surfaces” and the target surface.

For more information about using contact with NX Nastran Solution 701, see Nonlinear Analysis Theory and Modeling guide.

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4.4.3.4 ABAQUS Contact Properties (ABAQUS tab) The ABAQUS-specific section allows you to specify parameters found on the *CONTACT PAIR option and the *FRICTION entry, as well as the thickness/area for input for 1 or 2-D contact. This dialog box is broken into three separate segments, Friction Values, STEP Controls, and Other. Friction Values ...are included on the *FRICTION card in ABAQUS. Some interesting options include Friction Type, Slip Value (dependent on Friction Type), and Decay Exp (parameter allows separate static and dynamic (kinetic) friction coefficients with a smooth transition zone defined by an exponential curve). STEP Controls ...Max Slide Distance and Approach, are input to the *CONTACT PAIR option. Max Slide Distance limits finite sliding in 3D deformable contact. Approach activates automatic viscous damping for a contact pair. On this dialog box, the STEP Control options apply to the load set. To turn on these options in a time step, you must specify them on the ABAQUS STEP Options dialog box. For a detailed process, see Section 8.2.1.1, "Preparing the Model for Analysis" in the FEMAP User Guide. Other Typically, the most important input in this section is the Critical Penetration (HCRIT in ABAQUS). This value defines the maximum allowable penetration of a slave node into a master surface. Penetration values above this value will cause ABAQUS to abandon the current increment and start again with a smaller increment. This value can greatly affect convergence and accuracy of the overall solution. Note: If Connect Type is set to “1..Glued” a good idea is to click the Defaults button at the bottom of the Define Connection Property dialog box. This will turn on the Tied and Adjust options that are typically used in conjunction when created “Tied” contact in ABAQUS. Surface to Surface Contact (TYPE=SURFACE TO SURFACE) must be specified for shell thicknesses to be included during contact instead of using nodal locations (default). This option is only available when the Small Sliding and/or Tied options are also turned on. For a description of the other parameters, see the ABAQUS Standard and Explicit User’s Manuals.

ANSYS Contact Properties (ANSYS tab)

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4.4.3.5 ANSYS Contact Properties (ANSYS tab) The ANSYS-specific section allows you to specify the real constants on the TARGE169 (2-D), TARGE170 (3-D), CONTA171 (2-D), CONTA172 (2-D with midside nodes), CONTA173 (3-D), and CONTA174 (3-D with midside nodes). Contact surface elements are associated with target segment elements through a shared set of real constants, and ANSYS only looks for contact between surfaces with the same real constant set. Only contact elements and target elements of the same dimension (2-D or 3-D) can be in contact with each other.

For complete definitions of these real constants, see the ANSYS Element Reference Guide as well as the ANSYS Structural Analysis Guide. This dialog can be used to specify additional contact parameters. All of these parameters correspond to KEYOPT entries on the ANSYS contact and target elements. These are more advanced options used to create contact models which require additional parameters. The check boxes in the KEYOPT Overrides section of the dialog box allow you to toggle between two options for KEYOPTs (2), (4), (5), (8), and (11). The pull-down boxes in the lower portion of the dialog box correspond to KEYOPTs (7), (9), and (12), which offer additional options that can be chosen to create a more realistic contact model. Be sure to review the ANSYS Element Reference Guide as well as the ANSYS Structural Analysis Guide before beginning any type of nonlinear contact analysis. Note: If Connect Type is set to “1..Glued” a good idea is to click the Defaults button at the bottom of the Define Connection Property dialog box. This will choose an appropriate setting for Surface Behavior that will create “Bonded” contact in ANSYS.

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4.4.3.6 MSC.MARC Contact Properties (MARC tab) Pick the MARC tab to specify parameters found on the *CONTACT and *CONTACT TABLE options.

Contact Options This section contains all property inputs for the *CONTACT TABLE option. They will also be used in the *CONTACT option if the property is chosen. For details, see Section 8.6, "Marc Interfaces" in the FEMAP User Guide. You can specify the tolerance for contact (when two bodies are considered touching), the separation force to separate a node from a body, and an interference closure amount. In addition, if you choose No Relative Contact Disp, the glue option will be invoked. Stick-Slip Model, Rigid Plasticity, Friction Values, Contact Checking, Separation Checking The remaining contact parameters are only relevant if the contact property is chosen in translation to be output to the *CONTACT option. In most cases, the defaults will be chosen if none of the options are selected for the contact property. Refer to your MARC Program Input Manual for descriptions of these options.

LS-DYNA Contact Properties (Dyna Tab)

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4.4.3.7 LS-DYNA Contact Properties (Dyna Tab) Usually, the most important option is the Type (found in the General section) of contact you want to define. You can select from 13 different types of contact including Automatic, Eroding, Constraint, Rigid, Tied, etc. If you select an option that requires additional information beyond the standard inputs, you must determine the options needed and enter this information. If not, errors may result, or at minimum your analysis will run with all defaults, which may or may not be appropriate.

The General portion of the dialog box also contains options to choose ONE_WAY contact for those types of contact that support this (default is two-way contact between surfaces). An offset for TIED contact types can be toggled on and off, as well as a toggle to use a penetration formulation, which can also be based on the shortest diagonal. This rest of the options found on the DYNA tab allow you to specify additional contact parameters for LS-DYNA. The Friction, Scale Factors, Thickness Overrides, Time Activation, and Output sections are pertinent for all contact types. If no values are input or set, the defaults will be used. The Rigid, Tiebreak, and Eroding sections of the dialog box contain information specific to certain contact types. If you have selected one of these options from the Type drop-down in the General section, you will want to specify the appropriate information. Refer to your LS-DYNA User’s Manual for more information for each of these options.

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The Optional ABCD button will display the LS-DYNA Contact ABCD dialog box.

This dialog box has a slider control at the top of the dialog box which allows you to choose what level of “ABCD” contact you would like to be using. As the slider is moved from left (Off) to right (A to AB to ABC to ABCD), different areas of the dialog box become available. Again, please refer to your LS-DYNA User’s Manual for more information for each of these options.

NEi/Nastran Contact Properties (NEiNastran tab)

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4.4.3.8 NEi/Nastran Contact Properties (NEiNastran tab) Pick the NEi/Nastran tab to specify fields found on the BSCONP entry for NEi/Nastran. Please consult your NEi/ Nastran documentation to determine the correct usage of Connection Region and contact property cards before beginning contact analysis.

Static Friction Coefficient, Frictional Stiffness for Stick, Stiffness Scale Factor These parameters need to be set for you to attain accurate results from contact analysis from NEi/Nastran. These factors will be entered on the BSCONP entry of your NEi/Nastran input file. Penetration Type There are several options when choosing the penetration type for NEi/Nastran. •

1..Unsymmetric



2..Symmetric



3..Unsymmetric weld



4..Symmetric weld



5..Unsymmetric bi-directional slide



6..Symmetric bi-directional slide



7..Unsymmetric rough contact



8..Symmetric rough contact

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9..RBE3 element



10..Offset welded contact

Please refer to NEiNastran documentation to determine which Penetration Type will work best for your analysis. Other Penetration Factors These parameters need to be set for you to attain accurate results from contact analysis from NEi/Nastran. These factors will be entered on the BSCONP entry of your NEi/Nastran input file. Either a value for MAXAD or values for MAXNAD and/or MAXRAD may be entered for each Connection Property.

4.4.4 Connect, Connection Region... The Connect, Connection Region command creates the individual segments for contact. When you access this command, you will see the Connection Region dialog box.

This dialog box is partitioned into four major sections: standard entity information, Defined By, Type, and Output. Each of these sections are described more fully below. In addition, Add includes one item, Multiple allows you to select multiple entities, Reverse swaps “positive side”/“negative side” for surfaces or “Face 1”/”Face 2” for elements, Delete removes the highlighted items from the list, and Reset removes the entire list. Note: An entity is not selected until it appears in the large window on the right of the dialog box. Thus, an item manually entered in the entry area (shown as Surfaces above) will not be included if you enter the entity and press OK. You must select 1.0 will create smaller elements near the “start” of the extrusion, while a value < 1.0 will create larger elements at the “start” of the extrusion. There are three options available to define the total length of the extrusion: 1. Use Vector Length - uses the length of the vector that you defined for the total extrusion length. 2. Locate - The extrusion length is calculated from start of the extrusion to a defined location. If you choose this method, you will be asked to define the location (with the standard coordinate dialog) when you press OK to create the extrusion. If the location that you specify is not along the extrusion vector, it is projected onto that vector, before the length is computed. This method is a good one to use if you are trying to match another existing mesh, or geometry. You can simply pick nodes or points for the location to extrude to, without worrying about the actual dimensions. 3. Distance - this method requires direct specification of the extrusion length. The vector length is ignored, in favor of the distance you specify here. This method is a good one if you have a series of extrusions, along the same vector, and you know the distances or “stations” where you want the extrusions to end. You never need to redefine the vector, just keep specifying new distances.

5.5.1.3 Mesh, Extrude, Element Face... ... creates elements by extruding faces of existing elements. Operation of this command is essentially the same as Mesh, Extrude, Element described in the previous section. You pick the element faces, then edge faces are extruded into planar elements, and planar faces are extruded into solid elements. The primary difference between this command and simply extruding elements is the selection of the element faces. You will see a dialog box similar to the following:

Mesh, Revolve Menu

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This dialog box allows you to select the faces that you want to extrude. You can simply graphically pick faces one at a time and they will be added to the list, or you can press Multiple and choose multiple faces in the same ways that you can when applying loads to element faces (refer to Section 4.3.3.4, "Model, Load, Elemental..." for more info). Delete and Reset allow you to remove faces from the list. Before pressing Delete, select the face you want to remove. You may not select more than one face type - you can not select both planar faces and edges in the same command. Once faces have been selected, other options are the same as for extruding elements and plot-only elements created during command are always deleted after the extrusion has been completed.

5.5.2 Mesh, Revolve Menu The Mesh, Revolve commands are very similar to the Mesh, Extrude commands - they take existing curves, elements or element faces and create additional planar or solid elements. In this case however, the original elements are rotated (revolved) around an axis vector, rather than being translated along the vector as in the Extrude commands. The other major difference is that there are no Advanced options available for the Mesh, Revolve commands.

5.5.2.1 Mesh, Revolve, Curve... ... creates planar elements by revolving curves around a vector. Before you choose this command, define the mesh size along the curves that you will select. The mesh size will determine the number of elements created by each curve. Use the Mesh, Mesh Control, Size Along Curve command to define these sizes. To begin, you select the curves to revolve using the standard entity selection dialog box. Any type of curve can be selected, and the curves do not have to form a closed or ordered boundary. However, the generated elements will only be connected to each other at locations where the original curves were connected. Therefore, if you are trying to generate a connected group of elements (with no coincident nodes) it is always best to select a connected boundary in an ordered sequence around the boundary. You should not select any curves that cross the vector that you plan to revolve around. If you do, those curves will generate twisted elements since each end of the curve would revolve in a different direction. This command makes no allowance for generating triangular elements in the middle of a curve to eliminate this restriction. You can, on the other hand, choose curves that have endpoints on the axis of revolution. These curves will automatically create triangular elements (instead of quadrilaterals) at those endpoints. After you have selected the curves to revolve, you must specify the generation options. This is identical to the Mesh, Extrude, Curves command (see Section 5.5.1.1, "Mesh, Extrude, Curve..."). Next, the standard vector dialog box is used to define the axis of revolution. Unlike the extrude commands, the magnitude of this vector is not important, but its location and direction are important. The relationship between the location of the vector and the curves you selected determines how the elements will be created. Finally, you must specify the angle of rotation and the distance to translate along the axis of revolution. These values are just like those specified for the Mesh, Rotate commands, except you specify the total angle and total distance, not the values per iteration. The picture shows the result of revolving a series of curves (no translation distance was specified). Quadrilateral Elements Mesh Size controls elements along curves

Axis of Revolution

Original curves

Triangular Elements

9 elements along length of revolution

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5.5.2.2 Mesh, Revolve, Element... ... creates planar or solid elements by revolving existing elements around a vector - the axis of revolution. Line and planar elements can be revolved, but you can only choose one type in a single command. Line elements will create planar elements and planar elements will create solids as they are revolved. Using this command is essentially the same as the Mesh, Revolve, Curve command. First, choose the elements to revolve. Second, set the generation options using the dialog box shown in the Mesh, Extrude, Elements command. Next, define the axis of revolution using the vector definition dialog boxes. Remember, only the location and direction of this vector are important for this command. It is important to specify an axis that is properly positioned relative to the elements you selected. In general, it should be defined so elements will be revolved normal to their current positions. If you choose other locations or directions, it can result in badly shaped elements. In extreme cases like revolving plates in their own plane, this command will fail and will not create new elements. Finally, set the total rotation angle, and the translation distance (along the axis of revolution). Both of these quantities are input as the total values for the entire revolution. Line Elements

Revolve into Plates

Axis of Revolution

Plate Elements Quads with one corner on axis are split into two triangles and revolve into 4 tetras

Revolve into Solids Triangles revolve into Wedges Quads revolve into Bricks Axis of Revolution Quads on axis revolve into Wedges

5.5.2.3 Mesh, Revolve, Element Face... ... creates elements by revolving faces of existing elements. Operation of this command is essentially the same as Mesh, Revolve, Element described in the previous section. You pick the element faces, then edge faces are extruded into planar elements, and planar faces are extruded into solid elements. Refer to the Mesh, Extrude, Element Face command for more information on picking the faces to be revolved.

5.5.3 Mesh, Sweep The Mesh, Sweep menu allows you to select curves, elements or element faces, and then sweep them along one or more curves to form the new elements. Sweeping curves will form FEMAP planar (2-D) elements, while sweeping elements or faces will form either planar elements (if 1-D elements are swept) or solid elements (if planar elements are swept). Like the Advanced, Follow Curve option for the Mesh, Extrude commands, the curves or elements are swept along a curve. The Mesh, Sweep commands, however, keep the edge of the new elements tangent to the curve. The edges of elements generated with the Mesh, Extrude commands remain parallel to the edge of the curve but are not tangent to it.

Mesh, Sweep

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The menu includes three commands: •

Mesh, Sweep, Curve: Any type of curve can be selected, and the curves do not have to form a closed or ordered boundary. The generated elements, however, will only be connected to each other at locations where the original curves were connected. Therefore, if you are trying to generate a connected group of elements (with no coincident nodes) it is always best to select a connected boundary in an ordered sequence around the boundary.

Z

ZY X •

Mesh, Sweep, Element: Any line element or planar element can be selected. Line elements will be swept into quadrilateral plane elements. Triangular and quadrilateral plane elements sweep into wedge and brick solids, respectively. If you choose parabolic planar elements, they will create parabolic solids. Each element that you select will create one element at each step along the length of the curve.

V1

Y Z X •

Y X

V1

Y Z X

Mesh, Sweep, Element Face: This command is very similar to Mesh, Sweep, Element but instead of selecting entire elements, only element faces are selected. Refer to the Mesh, Extrude Element Face command for information on face selection.

Sweeping Curves and Elements Use the following procedure to sweep curves and elements: 1. Before you pick the Sweep command, define the mesh size using the Mesh, Mesh Control, Size Along Curve command for the curves (both the curves to sweep and the curve to sweep along). The mesh size will determine the number of elements created for each curve. 2. Pick the Mesh, Sweep, Curve or Mesh, Sweep, Element command. 3. Select the curves or elements to sweep using the standard entity selection dialog box. 4. Select the curve(s) to sweep along. 5. You will next see the Generation Options dialog box. To use the active element color and layer for the new elements, pick Use Current Setting. To use the color and layer of the original elements that you are sweeping, pick Match Original Entities. 6. Pick the Property for the elements that will be created. For curves and line elements to sweep, pick a plane element property. For plane elements to sweep, pick a solid element property. 7. If the curve to sweep along is planar, you do not need to pick any additional options. If the curve to sweep along is not planar, you can pick an Alignment Curve. Once you pick OK, you will be prompted for the curve. If you don’t choose an alignment curve, you will prompted to pick a reference point. The

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elements will be oriented toward either the point or curve(s) that you select. For examples, see "Sweeping Along a Non-Planar Curve".

Sweeping Along a Non-Planar Curve If you are sweeping along a non-planar curve, you must use either a reference point or alignment curve to orient the elements along the curve. The figure shows how two curves are swept along an out of plane curve. Note how the orientation of the elements stays relative to the alignment curve.

V1 Alignment Curve

Z

V1

Z

Y X Curves to Sweep

Y X

Sometimes you may prefer to use a reference point. However, poor placement of either an reference point or alignment curve can cause problems with the element orientation. In the example below, note how the element orientations are twisted.

V1

Z

Y X

Reference Point

V1

Z Curves to Sweep

Y X

Twisted Elements

6.

Viewing Your Model In addition to the numerous pre-and post-processing options provided by FEMAP, FEMAP also provides a wide array of viewing options that play a key role in increasing your FEA productivity. The options and methods for controlling how your model is displayed on screen can be divided into two broad categories: •

View and Window menu commands



groups and layers

Each of these areas and their associated commands are discussed more fully below. The commands on this menu control the display of your model on your computer monitor, on printed/plotted output, and in graphical data which is saved or transferred to other applications. Additionally, these commands help you to create and manage the graphical windows on your screen. FEMAP uses the term “view” to refer to the combination of the graphics window and all of the options that define what, how, and where your model will be displayed. FEMAP Views are stored with your model database. They can be either active or inactive. Active views are associated with an on-screen window. Inactive views are not currently displayed on your screen, but can be activated at any time you choose. Only non-iconic active views can be modified. The View menu is separated into five partitions. The first partition contains commands pertaining to creating and activating vies and multiple view manipulation. The second partition is view selection and options. Each of these areas is described more fully below. See Section 6.1, "View Activation, Management, and Options" The third through fifth sections all involve modifying the view, whether it be through magnification, rotation, etc. These topics are discussed further in Section 6.2, "Modifying the View".

6.1 View Activation, Management, and Options These commands allow you to: •

set which view is the “Active View” in FEMAP and whether the “Active View” or “All Views” will be updated by other view command.



set the Background colors and options



manage visibility of various entity types, labels, groups, layers, etc. in your FEMAP model



instruct FEMAP what type of plot to show (XY Plot, Deformation, Contour, Free Edge Plot, Model Only, etc.)



control viewing options for individual entity types (Labels, Colors, Show/do not show, etc.), tools and view styles (Filled Edges, Transparency, View Axes and Legend, etc.), and Postprocessing (Deformed Style, Contour/Criteria Levels and Legend, Beam Diagrams, XY Plot options, etc.)



use advanced post-processing options (Control Animations, Dynamic Cutting Plane, Dynamic IsoSurface, etc.)

6.1.1 View, Create/Manage... ... displays the View Manager, which allows you to create a new view using the New View button. The new view will become the active view when created. The Update Title, Delete View, and Copy View buttons can be used to update the name, delete, or copy the view currently highlighted in the Available Views - Selected View is Active list. The Title Filter and Clear Title Filter icon buttons can be used to filter the existing views appearing in the list by Title. In order to view any or all of the views in the list, use the Window, New Window command, select Load Views option, then select the view(s) you would like be visible (To select multiple views, hold down the Ctrl key while picking from the list). Once these views are visible, you can toggle between the views by clicking on the “view tab” of a particular view. You can also use the Window, Tile Horizontal; Window, Tile Vertical; and Window, Cascade commands to position multiple views on the screen at once.

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Viewing Your Model

Please refer to Section 6.3.1.1, "Window, New Window...", Section 6.3.1.3, "Window, Tile Horizontal", Section 6.3.1.4, "Window, Tile Vertical", and Section 6.3.1.5, "Window, Cascade" for more information on these commands.

6.1.2 View, All Views...

Alt+F7

... alternately turns the All Views switch on and off. When the “All Views” switch is on, a check mark will appear in the menu beside this command. No input is required for this command. When All Views is off, only one window, the active one, will be redrawn or modified. The active window is always the one that you last selected. If you do nothing else, the last window that you activated will still be active. Simply clicking with the left mouse button in a graphics window will select it as the active graphics window. You can also click the “View tab” of any view to make it the active view. When All Views is on, FEMAP will redraw all of the on-screen windows. Similarly, the other view-related commands will update all of the on-screen windows. You can therefore limit updates to a selected set of windows by closing views you do not want updated. After you make the changes you want, you can load the views back into the model using “Load View(s)” option of the Window, New Window command. Instead of using this command, the same All Views switch can also be controlled from the various dialog boxes which are displayed by the other View commands. You will see a check box named All Views in the upper right corner of each dialog box. If the box is checked, All Views is on - all of the currently loaded views will be updated.

6.1.3 View, Background... ... controls the background color of the on-screen window. Using the View, Background command you can set the background color for your graphics windows. You can select a solid background color. In this case, the color that you select fills the entire window background prior to drawing your model. You should normally pick a color for your background which is a solid (non-dithered) color. You can pick any color, but dithered colors can make it difficult to see your model. New models created with FEMAP models and Neutral files from previous versions (version 8.3 and below) will be brought in with their exiting background colors. The default setting for new models is the shaded background (option 0..Vertical). There are 9 different options for a shaded back ground in FEMAP: Vertical - The background color is shaded smoothly from the selected Top Color to the selected Bottom Color. Horizontal - The background color is shaded smoothly from left to right using the selected Top Color (left) to the selected Bottom Color (right). Diagonal Up - The background color is shaded smoothly from lower left corner to upper right corner using the selected Top Color (lower left corner) to the selected Bottom Color (upper right corner). Diagonal Down - The background color is shaded smoothly from upper left corner to lower right corner using the selected Top Color (upper left corner) to the selected Bottom Color (lower right corner).

View, Background...

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Square Spot - The background color is shaded smoothly from a square spot at the center of the screen (Top Color) to the 4 corners of the window using an “X” shape that stretches to each corner.

Circular Spot - The background color is shaded smoothly from a circular spot at the center of the screen (Top Color) to the outer edges of the graphics window.

Horizon - The background color is shaded smoothly from the top of the screen (Top Color) to the bottom of the screen (Bottom Color) with the middle of the screen being the Middle Color. The position of the middle color is determined by the horizon % (The horizon percentage goes from 0-100% with 0% at the top of the screen and 100% being the bottom of the screen).

Bitmap - The background color is solid (Top Color) and the Bitmap image selected in the Background field of the Background Bitmaps section of the View and Graphics Preferences dialog box. The bitmap is centered and shown

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Viewing Your Model

in the resolution selected in the Background Bitmaps section of the View and Graphics Preferences dialog box. For more information, see Section 2.6.2.2, "Views".

Stretched Bitmap - The Bitmap image selected in the Background field of the Background Bitmaps section of the View and Graphics Preferences dialog box is stretched to fit the entire graphics window. For more information, see Section 2.6.2.2, "Views" Hidden line displays will use the average color for the fill color. This option is only available in Render Mode graphics. If you print the screen using swap black and white and printer/plotter resolution, the background will not be shaded in the printed version. Logo This section allows you to show a bitmap logo anywhere in the graphics window. Show Bitmap - When on, shows the Bitmap image specified in Logo field of the Background Bitmaps section of the View and Graphics Preferences dialog box in the chosen position in the main graphics window. For more information, see Section 2.6.2.2, "Views". Logo Location - Allows you to position the logo anywhere in the graphics window, by selecting a position for the center of the bitmap. The entire logo will always be shown, so positioning the logo in the corner of the graphics window is accomplished by clicking at any point close to the desired corner.

Location of Pixel which determines color of logo transparency

Note:

FEMAP will try to make the background of the logo bitmap transparent. In order to do this, FEMAP takes the color of the pixel located in lower left corner of the logo and makes that color transparent for the entire logo. If you would like the background of your logo to appear (as in the picture above), change the pixel in the lower left corner to a color that is not in the logo.

View, Visibility...

Note:

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When post-processing with a logo in a corner, the contour legend can be positioned and shrunk using the View, Options command so the logo and the contour legend do not overlap. For more information, see Section 8.3.11, "Contour/Criteria Legend..."

6.1.4 View, Visibility...

Ctrl+Q

... allows you to control visibility of Entity Types, Entity Labels, Groups (one or multiple), Layers, Load Sets, Constraint Sets, individual pieces of Geometry (Solids, Sheet Solids, and General Bodies), Connection entities (Connection Regions and Connectors), Coordinate Systems, Aero entities, Freebody entities, and sets of Elements based on Element Shape, Element Type, associated Material, and/or associated Property.

Title Filter

Clear Title Filter

Each tab of the Visibility dialog box controls different aspects of what is displayed in the FEMAP graphics window. Combinations of settings on multiple tabs give the user a vast array of options for creating the desired display. Note:

Only tabs of entities which currently exist in the active model will be shown in the Visibility dialog box.

The two buttons at the bottom of the dialog box, Reset All and Done are available while in any tab. Done closes the Visibility dialog box, while Reset All returns the model to the “default display configuration” of FEMAP, which is: •

All Entity Types, Geometry, Connection entities, and Coordinate Systems displayed



Labels on for Coordinate Systems, all Constraints (including Permanent and Equations), and all Loads



View All Layers option set on Layer tab, Show Full Model option set on Group tab.



View Active Load Set and View Active Constraint Set options set on Load/Constraint tab.



All Element Shapes, Element Types, and Elements associated with all Properties and Materials displayed

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Viewing Your Model

The number and functionality of buttons on the right side of the dialog box changes for each tab. Once displayed, certain entities may or may not be available for selection based on the visibility options. For instance, if Elements are turned off on the Entity/Label tab, no Groups are being viewed (i.e., Show Full Model option), all Layers are currently visible, and all Element shapes, Element types, and elements associated with all Materials and Properties are also displayed, then elements are still available for selection in the graphics window. On the other hand, only entities in displayed Groups, on visible Layers, and Elements of types, shapes, and associated to Properties and Materials which are currently checked “on” in the Visibility dialog box or the Model Info tree are available for selection from the graphics window. Note:

The Visibility settings on the Entity/Label, Group, Layer, and Load/Constraint tabs apply to the Active View only. Settings on the Element, Material, and Property tabs apply to All Views in the model.

Filter/Clear Filter buttons The Filter and Clear Filter buttons are available for use in the Group, Layer, Material, Property, and Geometry tabs of the Visibility dialog box. Simply enter text into the field, then click the Filter button. The list in that tab will be reduced to only those entries that contain the text you specified. You can now enter additional text, and press the Filter icon button again to further reduce the list. Press Clear All Filters icon button to return to the full list and start again. This can be especially useful in models which contain a large number of groups and layers. Quickly Choosing Visibility In addition to using the Visibility icon on the View Toolbar or using Ctrl+Q, you can also access the Visibility dialog box directly from the “Quick Access” menu. Simply press the right mouse button with the cursor anywhere inside any graphics window, and select Visibility.

Entity/Label tab There are times that you will want to quickly toggle on/off the overall visibility of entire entity types and/or the labels for various entity types. The Entity/Label tab of the Visibility dialog box provides a single place to perform both of these actions.

When Draw Entity is selected above the lists of entity types, visibility of each entity type is controlled by the check box next to the entity type name. When Labels is selected, visibility for the entity type labels is controlled by the

View, Visibility...

6-7

check box. Visibility and/or labels for portions of the list can be turned on/off using the “special” check box next to any entity type “header” (Geometry, Mesh, Connections, Constraints, and Loads). Two additional options exist when the Labels option is selected. When Entity Color is checked, all labels will be displayed using the same color as the entity. When Erase Background is checked, FEMAP will erase the area where the label will be drawn, prior to drawing the label. If you are labelling filled areas, it is often good to choose this option, as they are easier to read. The table describes the functions performed by each of the command buttons: Entity/Label Button

Function

All On All Off Selected On Selected Off Selected Only

Turns Draw Entity or Labels check box on for all entities. Turns Draw Entity or Labels check box off for all entities. Turns Draw Entity or Labels check box on for selected entities. Turns Draw Entity or Labels check box off for selected entities. Turns Draw Entity or Labels check box on for selected entities, while turning all unselected entities off. Entity Colors Changes Color mode to Entity Colors for all options. View Colors Changes Color mode to View Colors for all options. Note: The following buttons change the entire view (selections, alignment, magnification, etc.), not just the view options. Load View Updates the current view by restoring from the View library. Save View Store the current view in the View library Reset View Resets the entire view to FEMAP defaults.

Group tab This tab enables you to specify visibility options for groups which allow you to display only a portion of your model. Groups are essentially subsets of the model based on entity IDs, rules to include entities related to other entities already in the group (i.e., nodes on elements currently in the group), or limited by “clipping” regions.

Group Set to “Show”

Groups Set to “Hide” Referenced Group Set to “Show”

There are 4 visibility options for groups:

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Viewing Your Model



Show Full Model - Groups are not currently being used to only display a portion of your model.



Show Active Group - The “active” group will be used to only display a portion of your model. The active group can be changed by selecting a different group from the drop-down list.



Show Single Group - Any single group can be chosen from the drop-down menu and used to display only a portion of the model.



Show/Hide Multiple Groups - Any number of groups can be set to “Show” (Green Circle with “+”), “Hide” (Red Circle with “-”), or “Clear” (no marker in box) to create the desired display.

By default, the Group option is set to Show Full Model, therefore the entire model will be displayed. Activating an existing group will not change the display, but will allow you to graphically select entities from your entire model to place into the group. If you want to display only a portion of your model, switch this option to Show Active Group, Show Single Group, or Show/Hide Multiple Groups. Then only the entities which are in the appropriate group(s) will be displayed. The Show/Hide Multiple Groups option gives you the most flexibility when creating a display. Show All will change the “Show/Hide flag” of all groups to “show”, while Clear All will change the flag for all groups to “Clear”. You may also highlight any number of groups from the list, then click Show Selected (set flag for all selected groups to “Show”), Hide Selected (set flag to “Hide”), Clear Selected (set flag to “Clear”), or Show Selected Only (sets flag of selected groups to “Show”, while setting flags of unselected groups to “Clear”). Note:

When Show/Hide Multiple Groups is set and ALL Groups are “Clear”, the whole model will be visible.

For Example: In this model, there are 11 total groups. Individual groups exist for the elements of each color (7 groups). Also, one group containing both the blue and green elements, one group containing the red, yellow, and cyan elements, one group containing the top two rows of elements, and one “L-shaped” group.

“Green and Blue” Group

“Red, Yellow, and Cyan” Group

“Top 2 Rows” Group

“L-Shaped” Group

Here are a few visibility scenarios involving the Groups in this example model:

All Groups “Clear” (Whole Model shown)

“Orange” and “Purple” set to “Show”

“Blue and Green” and “Top 2 Rows” set to “Show”

View, Visibility...

“Cyan”, “Top 2 Rows” and “L-Shaped” set to “Show”, “Red” and “Blue set to “Hide”

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“Yellow”, “Top 2 Rows”, and “Blue and Green” set to “Show” “Blue” set to “Hide”

Layers tab Controls which layers will be displayed in the model. Also allows you to specify the Active Layer as well as the NoPick Layer.

New Layer icon button

The default setting is View All Layers. If you want to only view selected layers, change to View Multiple Layers, then “check” the layers you would like to see in the view. The All On and All Off buttons simply “check” or “uncheck” all of the layers in the model. Selected On will “check” the highlighted layers, while Selected Off will “uncheck” them. Selected Only will “check” the selected layers while also “unchecking” all of the non-highlighted layers. As you “check” or “uncheck” the boxes next to various layers, the display in the graphics window will update “on-the-fly”. In addition to controlling your display, visible layers may also be used to control entity selection. Only entities on visible layers and which are not on the NoPick Layer can be selected graphically. With the Active Layer option, you can also select the layer that will be used for entity creation. You may also use the New Layer icon button next to the Active Layer drop-down list to create a new layer in your model.

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Viewing Your Model

. Note:

By default, entities used for solid geometry construction (such as a boundary surface for an extrusion) are automatically deleted after being used. On the Geometry/Model tab of the File, Preferences dialog box, you can change the “Construction Geometry... when used” option to “1..Move to NoPick Layer”. When this option is set, the construction geometry will be moved to “9999..Construction Layer”, which is the default for the NoPick Layer. This can be used to prevent construction geometry from being selected for load or constraint application. If you need to access this geometry, change the NoPick Layer to “0..none” and you will be able to graphically select these entities. Be careful when doing this however, since this geometry may occupy the identical space as a solid face or edge.

Load/Constraint tab Here you can choose the load set and/or constraint set that will be displayed in the view.

By default, View Active Load Set and View Active Constraint Set are the selected options, therefore the active load set and active constraint set will be displayed. You can change the “active” Load Set and/or Constraint Set using the appropriate drop-down list. You may eliminate loads and/or constraints from the display by choosing the View No Loads and/or View No Constraints options. Also, you can select a particular set for display whether or not it is active by using the View Selected Load Set and/or View Selected Constraint Set options and selecting an existing set from the appropriate drop-down list.

Geometry tab This tab allows you to control the visibility of individual geometric parts in your model including Solids, Sheet Solids (single surface and multiple surfaces stitched together), and General Bodies. All surfaces, curves, and points related to a geometric entity which has visibility set to “off” will also no longer be visible in the display. The icon next to the title designates the type of geometric entity. A cylinder by itself represents a Solid, a cylinder and a surface represents a “Sheet Solid”, while a cylinder with a connected surface represents a “General Body”. Only geometric entities which are currently “checked” will be available for selection in the graphics window. This can make it very easy to perform “box”, “circle”, “polygon”, or “freehand” picking of geometric entities.

View, Visibility...

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.

General Body icon

Solid icon

Sheet Solid icon

This table describes the functions performed by each of the command buttons when in the Geometry tab: Entity/Label Button All On All Off Selected On Selected Off Selected Only

Function “Checks” boxes for ALL geometric entities in the list. “Unchecks” boxes for ALL geometric entities in the list. “Checks” boxes of highlighted geometric entities in the list. “Unchecks” boxes of highlighted geometric entities in the list. “Checks” boxes of highlighted geometric entities in the list, while “unchecking” boxes of geometric entities which are not currently highlighted.

Connection, Coord Sys, Aero Panel/Body, Aero Spline/Control Surface and Freebody tabs In the Connection, Coord Sys, Aero Panel/Body, and Aero Spline/Control Surface tabs, you can toggle visibility on/ off for both individual Connectors, Connection Regions, Coordinate Systems, Aero Panel/Body entities, Aero Splines, and Aero Control Surfaces. In the Freebody tab, you can toggle visibility on/off for individual Freebody entities while postprocessing. An overall “on/off” toggle for Freebody display is available in the Freebody tool of the PostProcessing Toolbox. This table describes the functions performed by the command buttons when in the tabs mentioned above: Entity/Label Button All On All Off Selected On Selected Off Selected Only

Function “Checks” boxes for ALL entities in the list(s) of a particular tab “Unchecks” boxes for ALL entities in the list(s) of a particular tab “Checks” boxes of highlighted entities in a list of a particular tab “Unchecks” boxes of highlighted entities in a list of a particular tab “Checks” boxes of highlighted entities in a list of a particular tab, while “unchecking” boxes of entities in a list of a particular tab which are not currently highlighted.

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Viewing Your Model

Element, Material, and Property tabs These tabs allow you to control the visibility of elements based on Element Shape and/or Element Type (Element tab) and elements associated with specific Materials or Properties in your model.

The number of elements of each type or shape is listed after the type name or shape name when in the Element tab. A special check box exists in the Material tab which allows you to toggle visibility on/off for “Elements with No Material” which include plot only, link, spring/damper, DOF spring, gap, laminate (reference several materials, not one), mass, mass matrix, rigid/interpolation, stiffness matrix, and slide line elements. A similar box exists in the Property tab for “Elements with No Property” which include plot only and rigid/interpolation elements. Note:

Element visibility using the Element, Material, and Property tabs applies to All Views in the model, not just the Active View like the Entity/Label, Group, Layer, and Load/Constraint tabs.

The “Nodes On” option is actually one option shared by the Element, Material, and Property tabs. When “off” (default), the nodes of “hidden” elements will also be hidden and not available for selection. When “on”, the nodes of “hidden” elements will be visible and available for selection. This table describes the functions performed by each of the command buttons when in the Element, Material, or Property tab: Entity/Label Button All On All Off Selected On Selected Off Selected Only

Function “Checks” boxes for ALL element shapes/types, materials, or properties (includes box for Elements with No Material/Property). “Unchecks” boxes for all element shapes/types, materials, or properties (includes box for Elements with No Material/Property). “Checks” boxes of highlighted element shapes/types, materials, or properties. “Unchecks” boxes of highlighted element shapes/types, materials, or properties. “Checks” boxes of highlighted element shapes/types, materials, or properties, while “unchecking” boxes of shapes/types, materials, or properties which are not currently highlighted.

View, Select and View, Options

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Only elements of shapes/types or associated with materials or properties which are currently “checked” will be available for selection in the graphics window. This can make it very easy to perform “box”, “circle”, “polygon”, or “freehand” picking of certain element types/shapes, materials, or properties.

6.1.5 View, Select and View, Options This section of the menu contains two of the most often used commands in FEMAP: View, Select and View, Options. View, Select controls the top level display options. With View, Select, you can control whether your model is displayed in hidden line or plain wireframe mode, turn on and off stress contours, animations, and deformed plots, etc. View, Options provides detailed control over how entities are displayed, i.e. what color elements are drawn with, whether or not labels for nodes are displayed, whether or not perspective is turned on, etc. View, Options also provides extensive control over post-processing display options that are more fully described in the post-processing section of this manual.

6.1.5.1 View, Select...

Ctrl+S or F5

... chooses what will be displayed in a view. You can select both the type of display and the model or postprocessing data which will be displayed.

The View Select dialog box is basically divided into two halves: •

The XY Style and Model Style radio buttons comprise the first half of the View Select dialog box. These options choose the method for display. You can choose any one option from these two groups of styles. If you choose a Model Style, your model will be displayed in the view, using all of the other specified visibility and display options. If instead you choose an XY Style, the view will contain a 2D, XY plot of the selected output data or function. “XY styles” are only available when you have output data available for post-processing or functions. The XY Data button displays an additional dialog box with options for XY plotting of Output Data, while XY Functions provides options for the XY plotting of functions.

For information on Model Style, see Section 6.1.5.2, "Choosing a Model Style". For information on XY Style, see Section 8.2.3, "Choosing an XY Style", Section 8.2.3.1, "Selecting Data for an XY Style" and Section 8.2.3.2, "Quickly Choosing XY Data". •

The second half of the dialog box consists of the Deformed Style and Contour Style option buttons. Here you can choose one option from each category to define the type of post-processing display. The default settings (None-Model Only) are used to create a normal model display which does not use any output data for post-processing. The settings of these options are ignored if you choose an XY style. The Deformed and Contour Data button displays an additional dialog box that allows you to select the output data that will be used when creating a post-processing display.

For more information, see Section 8.2.2, "Choosing Deformed and Contour Styles" and Section 8.2.2.2, "Selecting Data for a Deformed or Contour Style".

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Viewing Your Model

6.1.5.2 Choosing a Model Style FEMAP provides numerous styles in which you can display your model. Each style provides certain benefits. Choice of the best style depends upon what you need to accomplish. The following table describes all of the styles, their advantages and disadvantages: Style Draw Model

Features

Quick Hidden Line

Full Hidden Line

Free Edge

Free Face

Description Simply displays all entities.

Advantages

Disadvantages (GDI Graphics)

Fast. Everything visible. Usually best “working mode”. Good for screen selection. Draws all entities. Fast. Results in a plot Lines of the same which only shows color color, which overlap, boundaries. With proper alternately draw and color assignments can erase themselves. show property or material boundaries. Sorts all elements, Good for final display then displays from the and visualization of comback of view. Only plex 3D models. Can be shows entities which helpful for screen selecare visible - hidden tion in complicated modlines are removed. els. Same as Quick Hid- Same as Quick Hidden Line. den Line, but does additional checking to properly remove all hidden lines. Finds and displays all Can quickly point out element edges which holes or disconnections do not join to another in your model. element. Finds and displays all Can quickly point out element faces which disconnections between do not join to another solid elements. Reduces element. complexity of solid model plots. Can help to find duplicate plate elements.

Render

Complex 3D models can be hard to Yes visualize. Entities drawn on top of each other may make it difficult to locate a particular detail. Not usually appropriate for screen Not Used selection. Resulting display depends on your color choices.

Fairly Slow. Not usually best for Yes picking - many entities are not visible. Does not properly remove hidden lines for some elements (see Full Hidden Line). Slow.

Same as Quick Hidden Line

Not appropriate as a working mode. Yes Really just intended for checking your model. Usually not used for a working mode. Intended for checking model.

Yes

The pictures, below, show examples of the various model styles. Draw Model

Hidden Line

Free Edge

Free Face

Although the hidden line removal options do require substantial calculations, and are therefore somewhat slower, they can often be the best approach to understanding a complex model. This is especially true for 3D models. After

View, Options...

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you make the first hidden line display, FEMAP retains a display list of the sorted information. This dramatically speeds up redrawing hidden line views. For more information, see Section 6.3.2.1, "Window, Redraw..." and Section 6.3.2.2, "Window, Regenerate...". For solid element models, you can also use the Free Face option to simulate a hidden line view. In fact, you can even use this mode to show hidden lines in a different line style (like dashed), instead of removing them. To remove backfaces, use the Fill, Backfaces and Hidden option, in the View, Options command, and chose one of the Skip methods. Choose the Show All Faces method to show hidden lines as a different color/style, then go to the Free Edge and Face options and set the Free Edge Color to Use View Color. Finally, choose the color and line style you want to use. The XY Function button is used to select the function(s) that will be displayed when you choose the XY of Function display style. Even though this is obviously an XY plot, you must choose the function(s) to be displayed from Select Multiple Functions for View dialog box because it is a display of model information, not always post-processing information like other XY plotting styles. Up to 9 different functions can be displayed at one time.

Choosing Deformed and Contour Styles When you want to graphically post-process model output, you must choose one of the deformed or contour styles, in addition to a model style. Choosing None for either of these options disables that type of postprocessing. You will use None any time you just want to display your model. If you want to display a combined post-processing view, for example, a Deformed Contour, just choose both a deformed and a contour style. For more information on the options available and overall general post-processing capability, see Section 8, "Post-Processing".

6.1.5.3 View, Options...

Ctrl+O or F6

...controls how your model (or XY plot) is displayed in a view.

Choose category to change between option lists

Scroll down for more options

Choose option to display or change settings

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Viewing Your Model

You can control whether entities are displayed, labelling, colors, and hundreds of other options. You can also control the display of non-model entities, such as the view origin, workplane, and snap grid. Finally, this command controls all of the graphical post-processing options. All of these different options are controlled from the View Options dialog box. There are three basic parts to this dialog box. The Category option buttons choose the type of view options that you want to update. When you choose a category, the Options list is automatically updated. This list displays all View options that you can update for each category. You may have to scroll through the list, using the scroll bar, to see all of available options. To modify an option, simply select it from the list. You can do this either by pointing at it with the cursor and clicking the left mouse button, or by pressing the direction keys. As you select an option, the right side of the dialog box is updated. It displays various controls which allow you to set the option. The current option settings are loaded as the defaults.

The Standard View Option Settings There are eight standard controls which appear in the right side of the View Options dialog box. If the option you select does not need a particular control, that control will not be visible. In fact, none of the options use all eight controls, and most only use a few. The titles of the controls change depending on the option being updated. Each control however, has a similar function for all view options. We will therefore describe them in terms of overall titles. You can refer to the table at the end of this section for more detailed information on the settings that can be chosen for each option. That table also shows the titles for any controls that do not control the standard functions that are described here. In order, from top to bottom, down the right side of the dialog box, the controls are: Draw Check Box: If this control is checked, the related entities will be drawn, otherwise they will be skipped. Some view options use this control to turn something else on or off. Examples include label prefixes, line elements in a free edge check, element shrinking, and filling. Double-clicking the associated item in the Options list will toggle this control on and off. Label List: This list box is usually used to choose the labelling mode for entities. You can choose to turn all labels off, to label by ID, and many other settings. For certain view options, this list is used for other label-related options. Examples include font selections, label or legend positioning, and symbol sizing. Color Mode List: This list box controls how an entity color will be chosen. If you pick Entity Colors, the colors that you assigned to each entity will be displayed. If you pick Use View Color, the single color that you specify in the View Color control will be used. Choosing Use Layer Color will result in each entity being displayed with the color of the layer that it references. Depending on the view option you are updating, other settings are also available. Still other view options use this list to control settings like the legend style, XY curve style, or light source position for shading. View Color and Palette: Typically, this text box defines a single color for the selected entity option. To use this color, you must also choose the Use View Color setting from the Color Mode list. You can either type a color ID in the text box, or press Palette to select the color graphically. Additional Text Boxes: Below the View Color controls, there are two additional controls which are used to specify other numeric settings. Examples of this include scale factors, animation frames, shrink and lighting percentages, minimum and maximum criteria limits, and the view aspect ratio. Most options do not use these text boxes. Command Button: A few view options display an additional command button (located directly above Apply). Pushing this button will display other dialog boxes. The options that use these buttons are described later in this section.

Setting Multiple View Options Updating a view option is simple. You choose the category and option that you want to modify, and then change the available settings in the other controls. To modify other view options, just repeat the process. Pick a new Category, if necessary, and a new Option. Then change those settings. You can repeat this as many times as you want.

View, Options...

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Previewing and Cancelling Your Selections If you would like to see the effect of your changes, press Apply. This will redraw the current view, using the new settings. If you decide that you did not like the changes, just press Cancel to leave the dialog box. This will automatically restore all view options to their prior settings. To save your changes, you must press OK.

View Options Categories As described above, FEMAP splits the view options into three categories. Each category contains related options.

The Labels, Entities, and Color category contains all of the options that control the display of model entities. With these options, you choose whether entities will be drawn, if and how they will be labeled, and what colors will be used. Entity label sizes and styles are further controlled by the Label Parameter option that is also in this category. Other entity-related view options can also be found here. For example, you can control the display of element direction arrows, offsets, and orientation vectors, among others. The Tools and View Style category contains the options that control whether tools, like the workplane and snap grid, will be displayed. This category also contains options that control the style of the view. For example, you can choose, free edge settings, element filling, shading, perspective, and stereo options. Each of these will change the overall style of the view. Finally, you will find options in this category to control view-related items, such as the legend, origin, and view axes. The final category, PostProcessing, controls all of the graphical postprocessing options. These include all of the options for deformed, animated, vector, contour, criteria, and XY plots. None of these options has any impact, unless you have selected one of the post-processing options through the View, Select command.

Additional Comments on View Options Options that are not self-explanatory are described in the following paragraphs. Post-processing related items will be further explained in Section 8, "Post-Processing".

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Viewing Your Model

Labels, Entities and Color Options Label Parameters This option controls the format of all labels in your view. If you turn the prefix on, entity labels will be preceded by a single letter prefix which will identify the entity type. For example, Node 1 will be labeled N1, Element 23 will be labelled E23. With the prefix turned off only the number will be used. You can choose any of the listed fonts. Larger fonts can be easier to read for simple models, but often obliterate each other on complex models. The font must be available to Windows before you can use it. Note:

If the labels appear fine on the screen but are not printed properly, it is probably because your Windows printer driver does not support that font. Simply change the font and reprint.

The first two color mode options, Entity Colors and Use View Color, just draw the label. Label colors either match the entities that they are labelling, or else all labels are drawn using the single view color. The final two options, Entity, Erase Back and View, Erase Back, choose the label color, in the same way as the first two options. If you pick one of these options however, FEMAP will erase the area where the label will be drawn, prior to drawing the label. If you are labelling filled areas, it is often good to choose one of the “Erase Back” options - they are easier to read. In fact if you do not, you will not be able to see any labels that use the same color as the filled area. Render Offset enables you to control how much labels are pulled forward. As OpenGL uses depth buffering, labels can be covered or partially covered by other drawn entities. The Render Offset is a multiple of the font height. A value of 1 will correctly label elements that have a slope of up to 45 degrees to the screen. If elements have a steeper slope to the screen, a higher value may be required. Coordinate System... ... controls the display of user defined coordinate systems only. This is not used for the global (or view) axes. Use the View Axes display option to update those axes. There are several options for displaying user-defined coordinate systems using the Label and Color modes. Labels can be shown for the axes, coordinate system ID, both (default), or no labels at all. The axes can be shown as lines without arrows (default), with arrows, or as “Solid” arrows. There are four color options for each “arrow option”, Entity Color (default), View Color, Layer Color, or RGB (Red, Green, Blue). Here are some examples.

ID and Axes Labels, Entity Color Line

No Labels, Layer Color Arrow

ID Labels only, View Color Arrow

Axes Labels only, RGB Solid

Point, Curve, Combined Curve, Surface, Boundary, Volume,... ... controls the display of these entities. You can choose a color mode, label mode (typically ID or Mesh Attributes), and whether to draw the entity.

View, Options...

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Points can also be labelled with their definition coordinate system or defined mesh size. In the case of Mesh Size, any point that has a size defined will be labelled with the size value. Points which have no size defined will not be labelled. Points can be drawn as “+” symbols or dots - refer to the Symbols options. Curve - Mesh Size... ... controls the display of mesh symbols and labels along curves. The default setting, Symbols Only, will only display symbols on curves which have a mesh size defined along the curve. If a mesh size is implied from point or default mesh sizes, it will not be shown. The second labelling option, Size and Bias, works similarly. In this case however, numeric values for the number of elements along the curve and the bias are shown. The bias value is not displayed when it is 1.0 (a uniform mesh). The third labelling option, Symbols (all curves), will display symbols on every curve. If no mesh size is defined along the curve, the size will be determined from point and default sizes. The final labeling option, Symbols and Count will show symbols as well as a numeric value for the number of elements for all curves that have a mesh size set. Note:

To specify the number of digits displayed for any displayed “bias factor” value, enter a value other than “0” in the Digits field of the Contour/Criteria Style “option” in View Options. To display “bias factor” values using an exponential format, change the Label Mode of the Contour/Criteria Legend “option” in View Options to one of the Exponent options.

Curve and Surface Accuracy This option allows you to view the directions of curves and surfaces using the Parametric Directions options. An arrow is placed at the end of each curve, and arrows are shown on the surface divisions to designate the s direction of the surface. The directions canvery useful when meshing or defining Connection Regions. Text... ... controls the display of text. You can eliminate certain types of text from the view by choosing one of the visibility settings. Node... ... controls display of nodes. Nodes can be drawn as either an “X” symbol or as dots - refer to the Symbols options. Nodes can be labeled using ID, Definition Coordinate System, Output Coordinate System, or Superelement ID. Node - Perm Constraint... If you have permanent constraints applied to one or more of your nodes, these settings will determine whether or not they are displayed. If the Constraint view option is also on, permanent constraints will be combined with the nodal constraints at any node where both exist. You will be unable to distinguish graphically which degrees of freedom are permanent constraints, and which are nodal. To make that determination, you must turn one of the options off. Element... ... controls the display of elements. There are several different options for labeling (ID, Property, Material, Type, ID/Property/Material, and Layer), and color (Entity, View, Layer, Property, and Material) modes. Refer to the next several options for additional information on elements. Element - Directions If this option is turned on, FEMAP will display an arrowhead on one element side, or a vector normal to the element (planar elements only). If you choose the RightHand Rule Normal Style, the arrowhead indicates the direction of the element connectivity. For line elements, the arrowhead points at the second node. For planar elements, the arrow is always located on the last edge, and points at the first node. For solid elements, the arrow is located on the last edge of the first face, again, pointing at the first node. Face normals can be determined by using the right-hand rule in conjunction with the direction arrows. The normal points in the positive, right-hand rule direction. You may want to turn on Shrink Elements to see the relationships between arrowheads and elements.

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Viewing Your Model

Directions on “legs” of rigid elements will always be shown as arrows pointing from “dependent” node(s) to “independent” node(s). If instead, you choose the Normal Vector style, vectors will be drawn at the center of planar elements to indicate the positive normal direction. Element - Offsets/Releases... ... controls whether element offsets will be displayed. If this option is on, FEMAP will draw lines from the nodes to the offset locations, and then draw the element connecting the offset locations. FEMAP always draws offsets to their actual lengths. If you have very small offsets, you might not see them, even though they are displayed. Centerline of Beam Released Degrees of Freedom

Offsets

456

You can use the Release Labels option to display the degrees of freedom that are released. When this option is set, FEMAP will label each released degree of freedom at the appropriate end of the beam. FEMAP uses the numbers one to six to represent the six elemental degrees of freedom. Element - Orientation/Shape If this option is on, FEMAP will draw a vector in the direction of the element orientation. For beams and other line elements, this vector will either point toward the third node, or in the direction of the vector orientation that you specified. For plane elements, that have rotated material axes, FEMAP will draw the vector in the direction of the material axes. Element - Beam Y-Axis is very similar to this option. Orientation On

Offset Beams with Orientation Vectors

Plates with Material Orientation Vectors

The second list box, Element Shape, allows you to change how line and plane elements will be displayed. In the default setting, Line/Plane Only, these elements will simply be drawn connecting the nodes. Line elements will just be a single line, plane elements will be a triangle or quadrilateral. Switching to either of the other options lets you see more information for these elements. Line elements can be shown with a rectangular cross section, the actual input cross section, or a box denoting the stress recovery location. These options only affect line elements. There is no difference for solid or plate elements between Show Plates Fiber Thickness, Show Inertia Ratio, Show Cross Section or Show Stress Recovery Locations. The Show Fiber Thickness and Show Inertia Ratio settings display the cross section as a rectangle. For bar and beam elements, if you choose Show Fiber Thickness, the size of the rectangle is based on the stress recovery locations. If you choose Show Inertia Ratios, the rectangular cross section is based on the area and cross-sectional inertias (I1 and I2). Since the cross section may not really be a rectangle, the height and width of the rectangle shown may not be correct, but it will be representative of a rectangular cross section with the same inertia ratio (I1/I2). The area, I1 and I2 values must all be nonzero or no cross section will be shown. Element Shape On

Offset Beams

View, Options...

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Show Cross Section draws the cross-section of the beams based upon the input to the FEMAP cross section property generator. This can be an arbitrary surface shape or a standard shape. This sample shows the difference between drawing the beam cross section and just line representations. The beam cross section picture provides a much better physical representation of the actual model. Show Stress Recovery Locations will be identical to Show Cross Section, except it will draw a rectangular cross section based upon the stress recovery locations for all beams that do not have a defined cross section. As stated above, for all other element types, these four options produce identical results. For tubes and rods, the cross-section is based on the radius. Other line elements can not display a cross section. Planar elements will be expanded to show their thicknesses. If you have specified top and bottom fiber distances, these will be used. If you have not, or the element type does not support fiber distances, the element thickness will be used and will be centered about the nodal plane. There are many benefits to using this option. It allows you to graphically see your property data, find errors, and it provides a more realistic display. For beam/bar elements, it also helps you to determine if you have properly specified the beam orientations. Since the rectangular cross section rotates with the orientation vector, you can see how your beam is oriented. By choosing these different options, you can graphically check beam cross sections. Note:

Although possible, you should not display element thicknesses when you are doing contour plots. FEMAP does not adjust the contour data to the surfaces of the “thickened” elements and the resulting picture can be confusing.

Element - Beam Y-Axis... ... is similar to Element - Orientation. Instead of drawing the vector toward the third node, or vector orientation that you specify, this option will draw a vector in the true element Y-Axis. FEMAP will calculate cross products, using the element X axis and the element orientation to determine the Y-Axis. If the orientation that you specified is perpendicular to the element X-Axis, it will always be equivalent to the Y-axis. This option is only used for line elements. Element - Coordinate System... ... displays the “local element coordinate system” of solid elements only. The “local” system will be displayed with the origin of the “local” system at the centroid of each element Note:

The “local element coordinate system” displayed is determined using Nastran methodology, therefore this may not be applicable for other solvers.

Element - Weld... ... allows you to turn the diameter on and off for all of the weld elements in your model. The diameter for each weld is determined by the Weld property used by each element. Element - Rigid... ... has a toggle which allows you to turn on symbols indicating the independent and dependent nodes for all of the Rigid Elements in your model. Independent nodes are displayed as “filled-in” Square symbols at the nodal locations, while dependent nodes are displayed as “outline only” square symbols. You can also turn on the degrees of freedom for the independent nodes (all rigid element types) and dependent nodes (RBE3 interpolation and RSPLINE elements only) using the Label Mode

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Viewing Your Model

RBE2 - No Symbols and No DOF Labels

RBE3 - Symbols and DOF Labels

RBE2 - Symbols and No DOF Labels

RBE2 - Symbols and DOF Labels

RSPLINE - Symbols and DOF Labels

Load Vectors... ...controls the length of the displayed vectors on the screen. You can choose a Uniform style or Scale by Magnitude, which scales the vector length based upon the magnitude. You may also specify the magnitude which controls the length of the largest load. All other loads are scaled accordingly. Each load type is scaled separately. To prevent visual loss of small loads in a large model, you may also specify a Minimum Scale. All loads which would fall below this minimum are then scaled to the minimum. Load - Body... ...controls the display of translational acceleration (straight solid arrow), rotational acceleration (curved solid arrow with 2 arrowheads), and rotational velocity (curved solid arrow with 1 arrowhead) body loads in the graphics window. Labels, Location for the “rotational” body loads, and Color may also be set. By default, when only one of the above body loads is being applied in the “Active” load set, the corresponding symbol for that load will appear in the “middle” of the View Axis, oriented to the XYZ of the View Axis.

Translational Acceleration (-1 in Y-direction)

Rotational Acceleration (100 about X-axis)

Rotational Velocity (20 about X-Axis)

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When more than one body load is being applied, translational acceleration will be displayed in the YZ plane, rotational acceleration in the ZX plane, and rotational velocity in the XY plane of the View Axis.

Changing the Location from 0..View Axis to 1..Model, will only affect the position of rotational body loads. They will be shown with the same symbol, but will also show a dotted-line representing the rotation axis of the load within the model itself.

Load - Force, Moment and Torque, Temperature, Distributed Loads, Pressure, Acceleration, Velocity, Enforced Displacement, Nonlinear Force, Heat Generation, Heat Flux, Convection, Radiation, Bolt Preload, Fluid Tracking, Unknown Condition, Slip Wall Condition, Fan Curve, Periodic Condition... ... independently control the display of each load type. For forces, moments, accelerations, velocities, and enforced displacements, you can choose to display either the resultant load vectors or the load components. If you choose either Color/Component Mode option 0 or 1, FEMAP will display one vector for each load in the direction of the resultant load. If you choose option 2 or 3, FEMAP will display the components of the load. This will draw up to three vectors which are aligned with the global rectangular directions. It does not matter what coordinate system you used to define the load, the components are always drawn in global rectangular. In either case, the vectors will be colored based on the entity or view color, as is typical for all of the other view options. Bolt Preloads are for NX Nastran only (version 5.0 and above). The Fluid Tracking, Unknown Condition, Slip Wall Condition, Fan Curve, and Periodic Condition load types are for use with the FEMAP Flow product only. Note:

To specify the number of digits displayed for any displayed load value, enter a value other than “0” in the Digits field of the Contour/Criteria Style “option” in View Options. To display load values using an exponential format, change the Label Mode of the Contour/Criteria Legend “option” in View Options to one of the Exponent options.

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Viewing Your Model

When displayed, the various nodal forces are drawn as shown as in the diagram.

L1

Force

Acceleration

Moment Enforced or Torque Displacement

Enforced Rotation

Rotational Temperature Heat Acceleration Flux

Velocity

Rotational Velocity

Heat Generation

Elemental loads are drawn very much like nodal loads, but are located at the center (or along) the element face where they are applied. Directional elemental loads (like direction heat flux and distributed loads) also represent the direction in which the load will be applied. Distributed Load Convection

Radiation

Pressure

Temperature

Heat Generation

Heat Flux

Function dependent loads can be labelled with both the load value and the function ID that has been selected. The function ID is shown in parenthesis.

2.(1) 2.

Constant Load

Load Dependent on Function 1

Curve and Surface-Based loads can be Total Loads or individual loads. This is designated by a “T” prefix for the Total Loads.

Individual Loads (Value Only) Total Loads on Surfaces and Curves with “T” prefix

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Surface-based Bearing Forces are shown with these symbols.

Bearing Force with Normal to Surface option “On”

Bearing Force with Normal to Surface option “Off”

Bolt Preloads appear as a “nut and bolt” symbol on a bolt region.

Note:

Be careful in determining whether a “Bolt Region” actually has a bolt preload applied as the symbol for the “Bolt Region” is a “Bolt without a nut”

Constraint and Constraint Equation... ... control the display of nodal constraints and constraint equations. If you also have permanent constraints in your model, see "Node - Perm Constraint...". Also note that you can label both the degree of freedom, and the coefficients for constraint equations. Nodal Constraints with DOF labels

Nodal Constraints - Arrows with No labels

Nodal Constraints Pins, DOF labels

Nodal Constraints Triangles, DOF labels

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Viewing Your Model

You can draw constraints as either default (single triangle), pins (with circular tips), arrows (head of arrows is facing away from node) that are oriented in the direction of the degree of freedom, or triangles (points on triangle are pointed towards the node). This can give a better indication of constraints if local or non Cartesian displacement coordinate systems are used. You use the Label Mode to select this option. Also, when using pins, arrows, or triangles, the color mode can be switched to RGB mode in which constrained X Degrees of Freedom (DOF) will be shown in Red, constrained Y DOF in Green, and constrained Z DOF in Blue. Note:

To specify the number of digits displayed for any coefficient of a constraint equation, enter a value other than “0” in the Digits field of the Contour/Criteria Style “option” in View Options. To display coefficient values using an exponential format, change the Label Mode of the Contour/Criteria Legend “option” in View Options to one of the Exponent options.

Connector... ...controls whether connectors are visible, the color mode, and whether the label ID is plotted. Region... ...controls whether regions are visible, the color mode, and whether the label ID is plotted. Combined - Eliminated Points... ...controls whether points eliminated from display by combined/composite curve(s) and/or combined/boundary surface(s) are visible. Combined - Eliminated Curves... ...controls whether curves eliminated from display by combined/composite curve(s) and/or combined/boundary surface(s) are visible. Combined - Eliminated Surfaces... ...controls whether surfaces eliminated from display by combined/boundary surface(s) are visible. Aero Panel... ...controls whether Aero Panel/Body entities are visible, the color mode, and whether the label ID is plotted. Aero Mesh... ...controls whether the lines representing the divisions of Aero Panel/Body entities are visible, the color mode of the lines representing the divisions (default is 3..Contrasting Colors), and whether the IDs are plotted for Aero Elements (also called Aero Boxes), Aero Nodes, Aero Elements and Nodes, or No Labels on the “Aero Mesh”. Aero Interference... ...controls whether the “interference body” of Aero Panel/Body (Aero Body Type = 1..Aero Body) entities are visible, how the “interference body” is displayed: Lines, Symbols (default), or Lines and Symbols, and the color mode. Aero Splines... ...controls whether Aero Spline entities are visible, the color mode, and whether the label ID is plotted. Aero Control Surfaces... ...controls whether Aero Control Surface entities are visible, the color mode, and whether the label ID is plotted.

Tools and View Style Options Free Edge and Face This option is only used for free edge and free face displays. If All Elements is selected, line elements will be considered in the search for free edges, and plane elements will be considered in the search for free faces. Otherwise, only plane and volume elements are used in free edge calculations, and only volume elements are used in free face calculations. With All Elements active, a plate made of planar elements and framed with beams would have no free edges. If All Elements were off, the beams would not be considered. The same framed plate would have all of its outer edges free. The Parabolic Edges options are similar. If you skip midnodes, FEMAP only checks the corner nodes of parabolic elements. In this case, edges of linear elements that connect to parabolic elements will not be considered free edges. Similarly, only the corners of element faces are used in the free face calculations. If you use midnodes, FEMAP requires that all nodes on an edge or face must match. Otherwise, the edge or face is free. In general, you should

View, Options...

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always use the midnodes. This insures that you do not miss a true disconnection at the midnodes between two parabolic elements. The Free Edge/Backface Color options are primarily for free edge displays. However, if you choose Use View Color, backfaces in free face displays will use the Free Edge View Color. By adjusting this color, you can often get a better understanding of the front and back portions of your model. You can even create a pseudo hidden line plot with dashed lines by changing the View Color to a dashed line style. If you would like to display the free edges along with the remainder of your model, so that it is easier to locate them, choose the View, Draw Model option. The default Free Edge View color has been chosen so that they will still be visible with most element displays. Shrink Elements If this option is on, all elements will be reduced in size, by the percentage that you specify. A size of 100% means that the elements will not be reduced. A size of 0% reduces the elements to a point at their centroid. Shrink Off

Shrink On

Reveals Line Elements that were hidden with Shrink Off

Fill, Backfaces and Hidden Element Fill On

If Fill is on, elements in your model will be filled with color. Whenever it is off, just the boundaries of the entities will be drawn. For more information, see "Filled Edges". Fill can be used to fill elements with color for line contour and line criteria displays. If you choose filled contours or filled criteria, that will override this switch, since each element can only be filled once.

The Backfaces option allows you to automatically remove some element faces from the display. FEMAP calculates the normal (based on the right hand rule around the face) of each element face. If it faces forward, out of the screen, that face is not drawn when backfaces are being skipped. Since this removes information, and takes some additional computations, this option is normally off, i.e. Show All Faces. When you define solid elements, they are automatically constructed so that the faces on the “back” of each element, will be properly defined backfaces. Therefore, you can safely turn on the first level, Skip Solid Backfaces, and be reasonably sure that you will not lose any meaningful information. On the other hand, the final two options must be used very carefully. Since you determine the orientation of normal to planar elements by the way you connect them, the backface option may discard faces of planar elements which lie on the “front” of your model. It all depends on how you define their normals. If you do want to use these options, you must build your model so that all planar elements are defined with their normals pointing either “inward” or “outward” from the center of the model. Then choose the appropriate option to remove the elements that you want. The Hidden Line Option selections control how hidden line calculations will be done for solid elements. By default, FEMAP will calculate the free faces of all solids, and just display them in a hidden line view, along with faces from all planar and line elements. If you just want to see the solid elements, choose Free Faces Only, or if you want to see all faces being drawn - including interior ones - choose Draw All Faces. Be aware, however, that Draw All Faces is substantially slower, and will result in the same final picture unless you have element shrink turned on. You can combine the Free Face plot style and Skip Solid Backfaces to do a fairly quick, and accurate hidden line plot of complex solid element models.

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Filled Edges When elements, or other entities are filled, the normal entity color fills the interior. If this option is on, the boundaries will also be drawn. The color of those boundaries is determined by the color mode set for this option. If you choose entity colors, you may not be able to see the border, since it will probably match the filled area. Contrasting colors are also based on the entity color, but FEMAP automatically chooses a color which does not match that color. If you want to draw just the filled areas, with no edges, turn this option off. The Filled Edges on/off switch is used any time you turn on the Fill Element option, or for contour and criteria displays. The only exception is line criteria displays where the switch is ignored since turning off the edges would eliminate the criteria information. The Filled Edges color is only used when you set Fill Element on. It is not automatically used for contour and criteria displays. Instead, the colors currently chosen by the element option are used. The Section Cut Edges options determine whether element edges will be draw on section cutting planes. If displayed, these edges are drawn with the Filled Edge view color. Render Options Controls the viewing of surfaces and curves on solid models, as well as midside nodes for parabolic elements. These options have no effect unless you are in Render mode (see Section 6.1.5.1, "View, Select..."). •

The Curve Transparency controls whether curves are viewed even when hidden in hidden line mode. This option is typically off. Turning it on will enable you to view all curves even in hidden line mode. This can be helpful when you are previewing mesh settings.



You may use the Hatch Surfaces option to show parametric (or hatch) lines on the surface. This option is available for Draw Model and Hidden Line modes when in Render mode. The default is to show surfaces only (no hatching).



The Parabolic Edge/Face allows you to view or skip midside nodes while in Render mode. If you use midside nodes for viewing purposes, it can increase drawing times while in Render mode. If drawing time is significantly increased, you may want to skip midnodes when viewing and orienting your model, and use midnodes only when examining deformed plots. The skipping of midside node information on deformed plots may lead to misinterpretation of results.



Offset Factor and Offset Units control how element edges and surface edges are displayed in a solid model. If the values are both 0 (not the default), the element edges will have a stitched appearance, since they drawn in the same location as filled triangles. The Offset Factor is a percentage (0-200%) that defines how much the element edges will be pulled forward in the display. The Offset Units value is also a percentage that controls the appearance of the element edges on filled triangles when the model is displayed at an angle. (This value applies to Render mode only.) Generally, you should use the default values. You can adjust these values to improve the display for your graphics card. The recommended range of values is 25 - 150.

Transparency Allows you to set the level of “Auto Transparency” in the model. This number must be set between 0 and 100, 0 being fully opaque and 100 being completely transparent. The default value is 75%. This option is used to set the transparency level for use with the Transparency option on the View Style menu. This setting is also used when using the Transparent Highlight option found in the Window, Show Entities command, as well as, the menu of the Show When Selected icon found in the Model Info Tree and the Data Table dockable panes. For best results when using “Auto Transparency”, the value for Search Depth on the Render tab of the FEMAP Preferences dialog box should be set to a value of “0”. For more information, please see the Search Depth portion of Section 2.6.2.3, "Render". Shading When this option is on, FEMAP incorporates lighting effects into the display based on its model’s orientation to the light source and the location and type of the light source. You can perform shading in all graphics modes. However, some lighting effects are only available in certain graphics modes. You can use the Shading Mode options to shade either filled areas, lines or both.

View, Options...

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FEMAP can incorporate up to three lighting effects dependent on graphics mode: ambient, diffuse and specular. Ambient light is considered to be directionless. All surfaces are equally lit. On a very cloudy day, there is very little directional light from the sun and there are no shadows. There is still plenty of light. The light falling on and being reflected by an object is independent of its orientation and the location of the viewer. The level of ambient light is controlled by %Ambient. A value of 0% means that any entity not lit by diffuse or specular light will be completely dark. A value of 100% means that the ambient light will saturate the whole model and no diffuse or specular lighting will be visible. Diffuse lighting is directional. It comes from one direction but is reflected equally in all directions. The illumination of a surface is only dependent on the orientation of the light to the object. The location of the viewer does not alter the lighting. Diffuse lighting is common with matt surfaces. Specular lighting is directional. It is important for shiny objects. The level of illumination is dependent on both the orientation of the light and the viewer. The Light Location/Type option controls the light location and type. There are six options and their behavior depends on the graphics mode selected: Light Location/Type Viewer Screen Viewer Spot Screen Spot Model Model Spot

Render Mode Diffuse light at viewer location Diffuse light at screen location Specular light at viewer location Specular light at screen location Diffuse light at model location Specular light at model location

Windows GDI Mode Diffuse light at viewer location Diffuse light at screen location Diffuse light at viewer location Diffuse light at screen location Diffuse light at model location Diffuse light at model location

Basically, Render mode graphics supports all lighting locations and types. Windows GDI Mode graphics does not support specular lighting, but does support viewer, model and screen locations. Viewer location means that the light is located with the viewer. Model location means that the light is located at a point relative to the model origin and therefore moves with the model as the model is rotated. Screen location means that the light is positioned relative to the screen center (x to the left, y up and z towards the viewer). A screen location light does not move as the model is rotated. Screen and model locations are entered by pressing the Light command button. For plane elements, FEMAP does not consider the direction of the face normal when calculating the angle to the light source. Co-planar elements which have face normals pointing toward and away from the light source will be shaded identically. This will result in bright areas on the “back-side” of a plate model. It is necessary however, since FEMAP does not restrict the direction of plate normals. For solid elements in Windows GDI mode, where FEMAP controls the face normals, backfaces will receive only ambient light. Render mode will highlight backfaces, but hidden line mode will hide them. Note:

Because Windows cannot dither lines, many graphics boards will be unable to properly shade the lines in your view. You should therefore turn on the appropriate fill options along with shading. FEMAP and Windows will properly shade the resulting filled areas. If your graphics board supports a large number (>256) of colors, you will still be able to shade lines. If you try to shade lines on graphics boards with less colors, Windows will map the shaded color to one of its available colors. This can look strange on the screen. If you make a hardcopy on a color printer that can print a large number of colors, the lines will be properly shaded, even though they might look strange on your screen.

Perspective When this option is on, FEMAP will display a perspective projection of your model, otherwise axonometric (parallel) projections are drawn. You can control the distortion in the perspective projection by modifying the distance. Smaller values result in more distortion.

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Viewing Your Model

Perspective drawings can result in more realistic images, but take longer to draw. Additionally, because of the nonparallel transformations involved, FEMAP must fully rebuild the display lists whenever you zoom, pan, center, or magnify a perspective view. This is not required for non-perspective views. Perspective Off

Perspective On

Finally, although it may work, perspective views are not usually the best to use for graphical selection. Graphical selection is inherently two-dimensional. Since perspective projections distort any two dimensional object which is not perpendicular to the projection, you may be surprised at what is selected. If you do make graphical selections from perspective views, you should review what was really selected before you proceed. Axisymmetric Axis The Axisymmetric Axis shows the axisymmetric axis of revolution and the radial direction. This provides you with a visual cue for the plane and orientation of your axisymmetric model. You should use the direction that matches your solver (See 6.3.1 in the User Guide). The axisymmetric axis is also used to compute the orientation of loads on axisymmetric shell elements. There are several options for displaying the Axisymmetric Axes using the Color/Draw mode. The axes can be shown as lines without arrows (default), with arrows, or as “Solid” arrows. There are two color options for each “arrow option”, View Color (default), or RGB (Red, Green, Blue). See the View Options section on Coordinate System for examples of the different options. View Legend The view legend identifies the load (prefixed by L) and constraint (C) sets, the group (G), and the view (V) that are displayed in a window. You can choose to display either the IDs or titles of these items. There are 2 additional labeling options, 2..Titles and Model Name, which will include the titles as well as the file name of the model, including full directory path and 3..Titles, Model Name, Date which will also include the current time and date. You can also move the legend to any of the eight positions. View Legend with Titles

V: Default XY View L: 100 psi Pressure Loading C: Fixed Edges and Symmetry G: Plate Elements

View Axes Z Y X

View Axes The view axes represent the orientation of the global axes. They are normally displayed in the lower left corner of the view, but you can specify a new position by pressing Position. Here you can simply enter the location in percentages of the graphics window (from top left) where you want the axes to appear. You can also select the position graphically by pointing with the mouse and clicking the left button. There are several options for displaying the View Axes using Show As and Color/Draw modes. Labels can be shown for the axes or no labels at all. The axes can be shown as lines without arrows (default), with arrows, or as “Solid” arrows. There are two color options for each “arrow option”, View Color, or RGB (Red, Green, Blue). See the View Options section on Coordinate System for examples of the different options.

View, Options...

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Origin The origin of global coordinates is indicated by a circular symbol. This option can be used to turn this symbol on or off. Workplane and Rulers When this option is on, the workplane will be visible. The workplane is always present and active - even if it is not visible. Workplane

Rulers 12. 11.

Y

10. 9. 8. 7. 6. 5. 4. 3. 2. 1.

Workplane Grid

1. 2. 3. 4. 5. 6. 7. 8. Z

9. Y

10. 11.

X

12.

X

For rulers to be drawn, the Show Rulers option must be on, and the appropriate ruler options must be set in the Tools Snap To command. The color of both the workplane and the rulers is chosen by the view color. If the Fill Plane option for Plane Fill is selected, the workplane is drawn filled in. If a color is selected that is almost transparent, the workplane triangle is drawn transparent and the edges and rulers are drawn ignoring the transparency. This gives a good visual cue for the workplane location in complex models. This only works in Render Mode graphics. Workplane Grid If this option is on, the snap grid will be drawn, in the workplane. The style of the grid is controlled by the Tools Snap To command. If you define an Invisible grid in that command, you will not be able to see it, even though you turn this option on. You do not have to be snapping to the grid for it to be visible. Group Clipping Planes If you turn this option on, and you are displaying a group which uses one or more clipping planes, the clipping planes will be drawn. Symbols Controls the size and color of symbols. This includes the symbols drawn for points, nodes, constraints, loads and many more. Choosing a larger size makes the symbols larger. The Preview Color is used for the symbols (dots, vectors, planes...) which are drawn when you press the Preview buttons that can be found on many dialog boxes. You can control whether symbol elements are drawn. Symbol elements are gap, mass, mass matrix, link and DOF spring elements. If your model has a large number of these elements, graphics performance can be impacted and the screen can be cluttered. Preventing the drawing of these elements can improve performance and image clarity. An alternative way to handle this issue is to use layers. Note:

You may use the Render tab in File, Preferences to prevent symbol elements being drawn during dynamic rotation.

You can also choose whether nodes, points, and curve mesh size will be drawn as their normal symbols, or as single dots. If you choose the dot option, a single pixel is drawn - if you go to a printer or Metafile they will still be a single dot in the device resolution. The Load Len and Other Vec options allow you to customize the length of vectors that are displayed. If you want to display shorter vectors, reduce the numbers below the 100% default value. Larger numbers result in longer vectors. Load Len is used for all loads. Other Vec is used for everything else. Note:

You may also use the Load Vectors option under Labels, Entities and Colors to scale the load lengths as well as use a Uniform or scaled distribution.

Preview ... controls the symbol size and color of the “marker” used to show a location when the Preview button is used in any dialog box where a location may be specified.

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View Aspect Ratio ... controls how FEMAP will distort your model as it is drawn on the screen. With AutoAspect on, FEMAP will gather information about your display from Windows and will calculate an internal aspect ratio. This automatic calculation will attempt to correct for differences between graphics boards. It adjusts the aspect ratio, so that the true shape of your model is shown. For example, circles are drawn as circles, not ellipses. If you turn AutoAspect off, you can specify an Aspect Ratio that you can use to eliminate any remaining distortions, or to intentionally distort a view of your model. Aspect ratios that are larger than 1.0 will make your model appear taller than normal. Aspect ratios less than 1.0 will make it appear wider. You should never specify very large aspect ratios - the severe distortion introduces other display problems for coordinate system triads and other symbols. The default Aspect Ratio can be set using the File, Preferences command. Note:

FEMAP and Windows adjust the aspect ratio based on the normal aspect ratio of pixels for your graphics board. There is no way to determine the effect of the horizontal and vertical size settings on your monitor. For this reason, AutoAspect may not result in a true correction. You can either adjust your monitor sizes, or specify an aspect ratio manually.

Model Clipping Plane This option can be used to set up a clipping pane that affects all entities in the model, without the use of any groups. To use the Model Clipping Plane, check the Enable option and select an option for Clipped Side (Positive or Negative). When Clipped Side is set to Positive, ALL entities on the Positive side of the defined plane, based on normal direction, will be removed from the graphics window. Negative removes entities on the other side of the plane. Note:

If the Model Clipping Plane passes through the middle of an entity, such as a surface or element, a “partial entity” will be displayed. Also, entities will not appear “capped” based on the plane, so it is normal for entities to appear “hollow”.

The default Model Clipping Pane for all new models is the Global YZ Plane in the Basic Rectangular coordinate system. If you want to change the plane, click the Clipping Plane button and use the Plane Locate - Define Clipping Plane dialog box. Geometry displayed in “Wireframe” Cube with Sphere removed Plane not “Enabled”

Geometry displayed in “Solid” Plane “Enabled” Clipping Side set to “Positive”

Mesh displayed in “Solid” Plane moved to an XY Plane Clipping Side set to “Negative”

When the Model Clipping Plane is “enabled”, the plane can be dynamically moved perpendicular to the defined plane by holding down the “Alt” key and spinning the Mouse Wheel backward or forward. For picking, if an entity is partially visible, it should be eligible to be selected from the screen. Also, quick access to Model Clipping Plane options are available on the View Style menu of the View Toolbar. See Section 7.3.1.2, "Tools, Toolbars, View".

PostProcessing Options See Section 8.3, "View Options - PostProcessing"

6.1.6 View, Advanced Post These commands provide special animation capability. The View, Animation command provides controls for your animating plot. The Contour Model Data command allows you to view element quality or material/property values as contour, criteria, or beam diagram plot. The other four commands provide special “move through” viewing using OpenGL for post-processing. For more information, see Section 8, "Post-Processing".

Modifying the View

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6.2 Modifying the View The last three sections of commands on the View menu all involve modifying the active view. These commands provide capability to rotate, pan, zoom, and align your model. They can be very helpful to orient your model in different positions for both checking and entity selection purposes. Many times, however, it is easier to use the Dynamic Rotate, Pan, and Zoom capability to quickly manipulate the view. In Render mode you can access this capability simply by holding down the left mouse button, while the View Toolbar buttons provides this capability in Windows GDI mode. This is especially convenient since this command is available while in another menu command, except other View commands. An explanation of these menu commands are provided below.

6.2.1 View, Rotate Menu The commands on this menu provide two basic capabilities to rotate the view of your model. View, Rotate, Model provides precise control of rotation angles, coordinate systems to rotate around and quick access to predefined views. View, Rotate, Dynamic provides flexible interactive manipulation of the view.

6.2.1.1 View, Rotate, Model...

Ctrl+R or F8

... rotates the current view. If you have multiple views open in the model, this command will only update one view at a time, unless you have the All Views option checked. When All Views is checked, the first action taken in the View Rotate dialog box will “sync” the views, then the views will move in unison until All Views is unchecked.

This command displays the View Rotate dialog box, which is very interactive. The current view orientation will be loaded as the default orientation. In Render mode, which is the default graphics mode in FEMAP, as soon as you make a change, FEMAP will always redraw your current view. This gives you instantaneous feedback on whether you have made the correct choice. If the new orientation is not what you want, you can immediately make a new selection. FEMAP always draws the entire model when you choose one of the standard orientation push buttons. In GDI graphics mode, FEMAP lets you abort any redraw by simply pressing a key, or the left mouse button. That selection will abort the previous redraw, update the orientation, and begin redrawing again. This allows you to decide how much of the redraw you want or need to see before you make your next selection. Using Rotate Around You may choose any defined coordinate system in FEMAP to Rotate Around (default is 0..Basic Rectangular). This includes local coordinate systems and the chosen coordinate system will be used by both the scroll arrows and the standard orientation buttons described below. You may also choose -1..Screen Axes to have rotation via the scroll arrows occur using the screen axes where the “screen” X axis is always horizontal to the right, Y is always upward and Z is always a vector perpendicular to your monitor (i.e., “out of the screen”). When -1..Screen Axes has been selected, the standard orientation buttons default to using 0..Basic Rectangular. Using the Scroll Arrows The three sets of scroll arrows, located near the left side of the dialog box, are used to rotate your view from its present position. As you click the scroll arrows, the view will rotate by the number of degrees currently defined in the Delta Angle text field. The axis of rotation is based on the scroll arrow you selected, and the selected coordinate system specified in Rotate Around. When -1..Screen Axes is selected in Rotate Around, rotations will be around the screen axes. Clicking the left scroll arrow rotates around the negative axis direction. The right scroll arrow rotates around the positive axis direction. You can accomplish the same rotations using the keyboard. First, you must select the desired set of scroll arrows. Press the Tab key until the appropriate set of scroll arrows is highlighted (essentially, press Tab once after the appropriate value field of the desired rotation axis has been highlighted). Then press the left arrow to rotate by

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Viewing Your Model

Delta Angle around the negative axis direction, or right arrow to rotate around the positive direction. PageUp and PageDown rotate by 45 degrees. When using the scroll arrows, remember: •

If you want the rotation to go faster, specify a larger Delta Angle.



The standard orientation buttons that are described later in this section automatically update the value of Delta Angle. The first six buttons change it to the value specified in the Delta field on the View tab of the File, Preferences dialog box (default is 10 degrees). The last three change it to 90 degrees. These automatic changes allow you to quickly select a starting point using these buttons, and then use the scroll bars to update that orientation.



In GDI graphics mode only, to quickly rotate your model around one axis multiple times, you must repeatedly press and release the left mouse button. FEMAP does not abort redraws if you just hold the button down in this graphics mode. Unless your model is small, the redraw time will significantly slow down your rotations.

Typing Rotation Angles Occasionally, you may know the rotation angles that produce the orientation that you want. If you do, you can type the angles into the three text boxes located just to the left of the scroll arrows. Remember, these angles are rotations about X axis, then the rotated Y axis, then the doubly rotated Z axis. They are not direction cosine angles. For more information on rotation angles, see Section 4.1.1, "Model, Coord Sys...". Selecting Standard Orientations Near the center of the dialog box you will see nine command buttons. These buttons will instantly switch your orientation to the appropriate predefined orientation. The first six buttons, XY Top, Bottom, YZ Right, Left, ZX Front, and Back, always align the view with one of the principal planes of the coordinate system selected from the Rotate Around drop-down list. You can use these to quickly look at your model from six orthogonal directions in relation to the chosen coordinate system. Note:

When -1..Screen Axes has been selected in Rotate Around, the standard orientation buttons default to using 1..Basic Rectangular.

The last three buttons, Isometric, Dimetric, and Trimetric, define three additional orientations. We have chosen orientations for these three buttons that are frequently used and correspond to their names. If you would like to use other orientations, you can use the File, Preferences command. Once the Preferences dialog box is open, click the Views tab to redefine the names and orientations of all three buttons in the View and Dynamic Rotation section. Mag, Zoom, and Pan These command buttons are shortcuts to the View Magnify, Zoom, and Pan commands. If you are updating a view, it is often more convenient to use these buttons than to press OK and then choose the command from the menu. Pressing any of these buttons automatically accepts any changes you have made - just as if you had pressed OK.

6.2.1.2 View, Rotate, Dynamic... ...allows you to dynamically rotate, pan and zoom your model curves and elements. When you choose this command, you will see the following dialog box:

If you are not in Render mode, your model will automatically switch to a wireframe, single color display of the curves and elements. All other entities will temporarily disappear. If you are in Render mode, the model will look the same. Whether you are in Render mode or not, the operations for the View, Align By, Dynamic operate the same. All operations (rotate, pan or zoom) are done by pressing and holding the left mouse button in the active graphics window, and then dragging the mouse either horizontally or vertically. For example, to rotate around the screen Y axis:

View, Rotate, Dynamic...

Press Left Button

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Release Button Drag Mouse

Z

Y

Y X

Z X

The following mouse actions are recognized, with the left button down: Rotate XY Mode Rotate Around -X Rotate Around -Y

Rotate Around +Y

Rotate Z Mode Rotate Around -Z

Rotate Around +Z Rotate Around +X Pan Mode

Zoom Mode

Pan Up Pan Left

Zoom Out (smaller)

Pan Right

Pan Down

Zoom In (larger)

For the Rotate Axis mode, moving the mouse to the right rotates counter-clockwise about the axis (right-hand rule), and moving left rotates clockwise. The dynamic mode can be chosen in several ways. The most obvious is to select one of the available buttons. Alternatively however, you can simply hold down the Alt key as you press the left button down to rotate around the Z axis. Press Ctrl to pan, or press Shift to zoom. Press Alt and Ctrl to rotate around the predefined axis. You do not have to hold the key as you drag the mouse, just make sure it is down before you press the mouse button. When you let go of the left mouse button, your model will begin to redraw in whatever mode that you have selected. That is with all entities and post-processing options. If you are not satisfied with the view, or need to do more transformations, simply press the button down again and drag it further. Hint:

These dynamic rotation commands can also be accessed at any time in Render mode simply by holding the left mouse button in the graphics window. You will then be able to rotate around XY. If you hold the Alt, Ctrl, or Shift keys down when first pressing the left mouse button, you can rotate about Z, pan, or zoom, respectively. Holding down Alt+Ctrl and pressing the left mouse button allows you to rotate around another axis that you define. No dialog box will appear. Also, if you have previously selected one of the buttons for Rotate Z, Rotate Axis, Pan, or Zoom, FEMAP will automatically default to this mode when you next access dynamic rotation.

If you have a three button mouse, you can use the middle mouse button instead of the left mouse button to dynamically rotate the model if a dialog box is open. This is only available in Render mode. FEMAP supports 3Dconnexion input devices (such as SpaceBall, SpaceNavigator, and SpaceTraveller) for dynamic rotation in Render mode. Sensitivity of motion can be controlled using the 3Dconnexion driver dialog box or from within FEMAP in the File, Preferences… dialog on the Spaceball tab. For more information, see Section 2.6.2.10, "Spaceball".

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Options... If you choose the Options button, you will see a menu that provides further control over the dynamic alignment command. Single Axis Controls how model XY rotations will be done. If you refer back to the previous diagram, dragging horizontally rotates around Y, dragging vertically rotates around Z. Normally, it is easiest to accomplish compound rotations by dragging along one axis for a while, then dragging along the other. Since it is very difficult to drag the mouse along a precisely horizontal or vertical axis however, the Single Axis option limits rotations to the single direction in which you are moving the greatest distance. Small deviations from horizontal or vertical will be ignored. If you turn this option off however, moving the mouse diagonally will perform a rotation about a diagonal vector. Model Axes Controls whether rotations will be around the default screen axes or around the model axes. If you are rotating around model axes, mouse movements are the same, they just apply to the corresponding model axes instead of the screen axes. AutoCenter In a three dimensional model, you will occasionally find that your model is rotating off of the screen as you move it with this command. You can either choose pan to bring it back, or press AutoCenter. AutoCenter is just like the View, Autoscale... commands, in that it calculates a new model center, but it does not change the scale at which the model is displayed. Use Rotation Center This menu item is simply a toggle that turns on and off every time you choose it. When it is checked, all rotations will be about the center of rotation that you specify with the Rotation Center command. If it is off, rotations will be around the View Center. Rotation Center... Allows you to specify a center of rotation to be used for future rotations. This does not change the location of the model on the screen like View Center does; it simply allows rotation around another location. When you choose this command, Use Rotation Center is automatically turned on. Rotation Axis... Allows you to specify a vector that will be used as the rotation axis, if you are in the Rotate Axis mode (Alt+Ctrl keys). When you specify a rotation vector, the base of the vector is automatically used to update the rotation center, so all rotations will be about that point. When you choose this command, Use Rotation Center is automatically turned on. Note:

This command does not account for any perspective that you have specified. It is usually best therefore to turn off Perspective before using this command.

Note:

All rotations are performed around the view center (or the rotation center, if you have turned on this option). If you only move the mouse slightly and a large rotation occurs, it is because that portion of the model you are rotating is well away from the center of rotation - possibly in the direction that is perpendicular to the screen. To avoid this, position the view center (or rotation center) on the geometry/mesh you are trying to rotate.

Limitations While the dynamic display capability will work with any graphics adapter (you do not need any special acceleration or 3D hardware), Render mode can provide significantly increased dynamic rotation speed and drawing with an OpenGL accelerator board. Following are some limitations of dynamic display: Render mode on or off: • The model is drawn in various styles depending on the View Style that is active and the type of elements in your model. For example, if you rotate a free-edge view, the free edges will be rotated. Render mode off: • The display is limited to a single color - depending on the color you choose for the window background.

View, Rotate, Single Axis

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There are limitations on the total number of nodes, and faces that can be displayed. Depending upon your model, and available memory you should be able to display models of around 3000-4000 faces. If your model is larger, you will still be able to use this function, but only the first 3000-4000 faces will be displayed - still probably more than enough to orient your model. If you are working with very large models, consider either activating a group to reduce the number, and choose the elements that will be displayed. Alternatively you can switch to a free edge display.



Hidden line removal can not be done during dynamic display.

Improving Performance of Dynamic Display FEMAP provides three different methods to redisplay your model during this command. Again, these methods are only applicable when you are not in Render mode. Depending on your computer, graphics adapter and graphics drivers, any one of these three methods may result in best performance. You should always experiment with these methods to find the one that works best on your system. The methods are selected using the Dynamic option of the File, Preferences command. Method Fast Redraw Reduced Bitmap Full Bitmap

Description Usually fastest for small models, but not good for large models unless your graphics adapter can draw vectors very rapidly. Some screen flicker. Fast on most systems. Little or no flicker. Basically the same as Reduced Bitmap. Will usually be slower - but not always.

Experiment with both small and large models to see which works best for you. In some cases the performance differences will be dramatic, depending upon the capabilities of your graphics adapter. When you have found the method that you like, remember to choose the Permanent button in File, Preferences to save your selection for future models.

6.2.1.3 View, Rotate, Single Axis This menu item is simply a toggle that turns on and off every time you choose it. For a further explanation of Single Axis, please refer to the Single Axis heading under View, Rotate, Dynamic... in Section 6.2.1.2, "View, Rotate, Dynamic...". This command can also be accessed from the Options menu on the Dynamic Rotations dialog box.

6.2.1.4 View, Rotate, Model Axis This menu item is simply a toggle that turns on and off every time you choose it. For a further explanation of Model Axis, please refer to the Model Axis heading under View, Rotate, Dynamic... in Section 6.2.1.2, "View, Rotate, Dynamic...". This command can also be accessed from the Options menu on the Dynamic Rotations dialog box.

6.2.1.5 View, Rotate, Rotate Around View Center This is the default “Rotate Around” mode in FEMAP. This menu item simply highlights when chosen and instructs FEMAP to rotate around the current “View Center” location in the “Active View”. The “View Center” is set using the View, Center command (See Section 6.2.7, "View, Center..."). The “View Center” is also reset to the center of the graphics window anytime a View, Autoscale... command is used (See Section 6.2.3.1, "View, Autoscale, All", Section 6.2.3.2, "View, Autoscale, Regenerate All", and Section 6.2.3.3, "View, Autoscale, Visible"). The “Rotate Around View Center” mode can be also be accessed using View, Rotate, Dynamic... (Section 6.2.1.2, "View, Rotate, Dynamic..."). In order for this “mode” to be set, the “Use Rotation Center” option must NOT be checked in the Options menu in the Dynamic Rotations dialog box.

6.2.1.6 View, Rotate, Rotate Around Rotation Center This menu item simply highlights when the “Rotate Around Rotation Center” mode is chosen. When it is checked, all dynamic rotations will be about the center of rotation that you specify with the Rotation Center... command (See Section 6.2.1.8, "View, Rotate, Rotation Center..."). It will be no longer be highlighted when the “Rotate Around” mode in FEMAP is changed to Rotate Around View Center or Rotate Around Rotation Axis.

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The “Rotate Around Rotation Center” mode can be also be accessed using View, Rotate, Dynamic... (Section 6.2.1.2, "View, Rotate, Dynamic..."). In order for this “mode” to be set, the “Use Rotation Center” option must be checked in the Options menu in the Dynamic Rotations dialog box.

6.2.1.7 View, Rotate, Rotate Around Rotation Axis This menu item simply highlights when the “Rotate Around Rotation Axis” mode is chosen. When it is checked, all dynamic rotations will be about the rotation axis that you specify with the Rotation Axis... command (See Section 6.2.1.9, "View, Rotate, Rotation Axis..."). It will be no longer be highlighted when the “Rotate Around” mode in FEMAP is changed to Rotate Around View Center or Rotate Around Rotation Center. The “Rotate Around Rotation Axis” mode can be also be accessed using View, Rotate, Dynamic... (Section 6.2.1.2, "View, Rotate, Dynamic..."). In order for this “mode” to be set, click the “Rotate Axis” radio button in the Dynamic Rotations dialog box.

6.2.1.8 View, Rotate, Rotation Center... ...allows you to specify a center of rotation to be used for future dynamic rotations. This does not change the location of the model on the screen like View Center does; it simply allows rotation around another location. When you choose this command, the Rotate Around Rotation Center mode is automatically set (See Section 6.2.1.6, "View, Rotate, Rotate Around Rotation Center") This “rotation center” can also be specified using View, Rotate, Dynamic... (Section 6.2.1.2, "View, Rotate, Dynamic...") by choosing Rotation Center... from the Options menu on the Dynamic Rotations dialog box.

6.2.1.9 View, Rotate, Rotation Axis... ...allows you to specify a vector that will be used as the rotation axis for dynamic rotation. When you specify a rotation vector, the base of the vector is automatically used to update the “rotation center”, so all rotations will be about that point. When you choose this command, the Rotate Around Rotation Axis is automatically set. The “rotation axis” can also be specified using View, Rotate, Dynamic... (Section 6.2.1.2, "View, Rotate, Dynamic...") by choosing Rotation Axis... from the Options menu on the Dynamic Rotations dialog box.

6.2.1.10 View, Rotate, “Standard Orientation Views” (Top, Bottom, Right, Left, Front, Back, Isometric, Dimetric, and Trimetric) ...these allow you to quickly access the “standard orientation views” specified in the “View, Rotate, Model” command in FEMAP. They are also available on the View Orient toolbar. See Section 6.2.1.1, "View, Rotate, Model..." for more information. Quick View Icons - Appear on the View Orient toolbar ...XY view

...XY view (reverse)

...YZ view

...YZ view (reverse)

...ZX view

...ZX view (reverse)

...Isometric view

...Trimetric view

...Dimetric view

View, Align By Menu

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6.2.2 View, Align By Menu The commands on this menu are alternatives to the View, Rotate command. They are also used to orient your model within a view. These commands are usually used when you want to orient the view relative to some geometry or other entities in your model. You can also use these commands to define an initial orientation, and then use View, Rotate to update the view relative to that starting point.

6.2.2.1 View, Align By, Coord Sys... ... automatically aligns the view to the XY axes of a coordinate system. This command displays a standard dialog box so you can select a coordinate system. The view will be rotated so that the coordinate system axes are aligned with the screen axes. That is, X horizontally to the right, Y up, and Z “out of the screen”.

6.2.2.2 View, Align By, Surface... ... automatically aligns the view using the normal vector of a selected surface. The view will be positioned so the normal vector points out from the screen towards the user.

6.2.2.3 View, Align By, Along Vector...

Ctrl+F8

... aligns the view to a specified vector. The standard vector definition dialog box defines the alignment vector. When you specify the vector, the view will be aligned so the vector you selected will be pointing into the screen. In the resulting view, your model will be oriented so that you are looking from the base of the vector, toward the tip. Since a vector really only defines one of the orientation axes, the rotation of your model about the orientation vector is undefined. This is the rotation about the screen Z axis (“out of the screen”). In general, FEMAP will align one of the global coordinate axes with the screen X (horizontal) axis. If you want to update this orientation, just switch to the View, Rotate command, and rotate the view about the Z screen axis. This will retain the vector orientation, but will rotate about that vector. Hint:

You can choose any of the available vector definition methods. This will enable you to easily orient your view relative to different entities in your model. You can also use the various snap modes to select the vector.

6.2.2.4 View, Align By, Normal to Plane... ... automatically aligns the view using the normal vector of a specified plane. Uses the standard Plane Locate dialog box. The view will be positioned so the normal vector points out from the screen towards the user.

6.2.2.5 View, Align By, Workplane... ... immediately aligns the view to the current workplane. No additional input is required. The workplane axes are aligned with the screen axes. The X axis is horizontal (to the right), Y is up, and Z is out of the screen. Hint:

If you want to align your view normal to a plane in your model, you can use View, Align By, Along Vector, or this command. To use this command, you must first use the Tools, Workplane command to align the workplane to the desired orientation. This approach allows you to use all of the standard plane definition methods for selecting the orientation plane.

6.2.3 View, Autoscale

Shift+F7

This menu provides several ways to automatically scale and move your model so that it is visible in your window.

6.2.3.1 View, Autoscale, All

Shift+F7 ...automatically centers and magnifies your model in the view. No additional input is required. To determine the automatic scale and center, FEMAP finds the maximum dimensions of your model in all three global directions.

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This essentially puts your model inside a “box”. FEMAP sets the center of the view to the center of that box. The scale is adjusted, so that you can rotate your model to any orientation without parts of it going out of the window. It is based on the longest, diagonal of the “box”, and the smallest window dimension. Depending on the real shape of your model, the shape of the window, and the orientation you have currently chosen, you may feel that the autoscaled magnification is too small. This can be especially true for long, thin models in non-square windows. If you need to enlarge the model use either the View, Zoom or View, Magnify command. Since no dialog box is displayed, you cannot choose between autoscaling one, or multiple views, during this command. Before you choose View, Autoscale, you must use the All Views command to select the views that you want to modify.

6.2.3.2 View, Autoscale, Regenerate All

Ctrl+Shift+A

If AutoScale All does not work, then... FEMAP maintains overall size information about your model in your database. This information is used to properly autoscale your model into the active window. If you have created some entities which were positioned at a large distance from your model, and then deleted or moved those entities, the autoscale calculations may still be based on the larger overall model size. This will result in scaling which is too small, and typically not centered, relative to your window. If you see this behavior, you can force FEMAP to recalculate all of the autoscaling information by choosing this command, or pressing Shift+Ctrl+A (instead of just Ctrl+A). This combination should restore your scaling to the proper size and centering.

6.2.3.3 View, Autoscale, Visible

Ctrl+A ...works just like the View, Autoscale, All command, except that it only uses considers the portions of the model that are displayed when doing the centering and scaling computations. This means that if you are only displaying geometry, then the nodes and elements in your mesh will not be used for the scaling (and therefore may be outside of the window). Likewise, the current group and layer settings are also considered. If you are displaying a group that only contains one corner of your model, then that corner will be scaled to fill the window and moved to the center.

Using Autoscale for XY-Plots If you have selected any of the XY-plot styles, View, Autoscale will set both the XY X Range/Grid and XY Y Range/ Grid options to Automatic. These selections display the entire XY-plot. The axis extents are determined from the data you have selected.

6.2.4 View, Magnify...

Ctrl+M or Ctrl+F7

... adjusts the scale of your model in the active view.

This command displays the View, Magnify dialog box. The current view scale is shown in the Magnification Factor edit control. If you know the scale factor you want, you can type it in this control and press OK. This method is also useful when you want to set All Views to the same scale factor Up 50%

Original

Down 50%

View, Zoom...

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Magnification factors are relative to the size determined by the View, Autoscale command. A magnification factor of 1.0 is always used for an autoscaled view. This does not mean that one inch in your model equals one inch on the screen. Larger magnification factors make your model appear larger in the view. The buttons near the center of the dialog box provide another method of adjusting the magnification. They adjust the magnification relative to the current setting. Up 10% and Up 50% make your model appear larger. Down 10% and Down 50% make your model appear smaller. When you press any of these buttons, or type a new factor, FEMAP will magnify around the center of the view. The Fill View button is similar to the View, Autoscale command. It too bases its calculations on the overall model dimensions. However, this button only considers the current orientation of your model. It projects the overall dimensions into the current view and then adjusts the magnification factor to attempt to fill the screen. This will always result in a larger image than View, Autoscale. If your model geometry is non-rectangular, or has cutouts, this option still might not fill the view. Unlike the other View, Magnify options, but just like the View, Autoscale command, the Fill View button will automatically adjust the centering of your model.

Rotate, Zoom, and Pan These command buttons are shortcuts to the View, Rotate, Zoom, and Pan commands. If you are updating a view, it is often more convenient to use these buttons, than to press OK and then choose the command from the menu. Pressing any of these buttons automatically accepts any changes you have made - just as if you had pressed OK.

Using Magnify for XY-Plots If you have selected any of the XY-plot styles, View, Magnify will set both the XY X Range/Grid and XY Y Range/ Grid options to Max Min. The minimum and maximum axes values are also adjusted to magnify the curves. For XY-plot styles, pressing Fill View results in the same image as the View, Autoscale command. You cannot type a magnification factor for XY-plot styles.

6.2.5 View, Zoom...

F7

... simultaneously updates the scale and centering of your model in the active view. The update is based on a rectangular area that you define relative to the window.

This command displays the View Zoom dialog box. You must choose between two zooming directions: Zoom In and Zoom Out. When you zoom in, FEMAP will enlarge the rectangular area that you define to fill the entire window. Zoom Out does just the opposite. The magnification is reduced, so that the portion of your model that had filled the entire window now only fills the rectangular zoom area. The four text boxes near the center of the dialog box are used to define two diagonal corners of the zoom rectangle. It does not matter whether you choose the upper-left and lower-right corners, or the upper-right and lower-left corners. It also does not matter which corner you specify first. The corner locations are specified in percentages of the window. The upper-left corner of the window is (0%,0%). The lower-right corner is (100%,100%). Upper-right is (100%,0%).

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The easiest way to specify the zoom rectangle is to use your mouse. First, make sure one of the Corner 1 text boxes is active. Then move the mouse, in the graphics window, to point at the first corner of the rectangle. Press the left mouse button. Then move the mouse to point at the diagonally opposite corner. As you do this, you will see the rectangular zoom area in your graphics window. Position it wherever you want and press the left mouse button again. Double-click the button instead, if you want to automatically select OK. If you have any of the cursor snap modes enabled, (Snap To Grid, Snap To Node,...) they may change the location you pick with the mouse. You can use this feature to your advantage if you want to use a node or point as the corner of the zoom rectangle. For more information on graphical selection, see Section 4, "User Interface" in the FEMAP User Guide. You can also just type the locations of the corners using the keyboard. If you choose this method however, you do not have the advantage of using the dynamic zoom box to position the zoom area.

Previewing the Zoomed View After you define the zoom area, you can press Apply to zoom, and redraw the view. This is just like pressing OK, except that the View Zoom dialog box is still present. You can still press Cancel to revert to the original view, or you can define additional zoom areas to further update the view.

Rotate, Mag, and Pan These command buttons are shortcuts to the View Rotate, Magnify, and Pan commands. If you are updating a view, it is often more convenient to use these buttons, than to press OK and then choose the command from the menu. Pressing any of these buttons automatically accepts any changes you have made - just as if you had pressed OK.

Using Zoom for XY-Plots If you have selected any of the XY-plot styles, View Zoom will set both the XY X Range/Grid and XY Y Range/Grid options to Max Min. The minimum and maximum axes values are adjusted based on the zoom area that you specify. This is probably the easiest way to choose particular sections of a complex XY plot. The zoom area that you choose should be inside the graph area - although it does not have to be.

6.2.6 View, UnZoom... ... returns you to the previous magnification and centering, after you have changed them with a zoom, magnify, pan, or center command. Choosing this command a second time will return to the original view. This provides a quick way to alternate between full-model, and detailed views. It also allows you to change your view to see other parts of your model, and quickly return to the original settings. Note: Only one level of previous zoom is saved. That means, for example, if you press the Pan buttons on the toolbar more than once, or you center, then magnify, you will only be able to back up one step - not return to the original position before you changed the view.

View, Center...

6.2.7 View, Center...

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Shift+F8

... chooses the model coordinates that will be located at the center of the view. This command does not change the magnification or orientation of the model. It just moves the specified coordinates to the center of the view. The standard coordinate definition dialog boxes are used to define the center coordinates. The center is entered in three dimensions because FEMAP will use this location as the center of rotation for the View, Rotate command. By precisely specifying the location you want, you can later rotate a view about any location in your model. Alternatively, if you just want to quickly center the current view, and you do not care about later rotations, the coordinate perpendicular to the screen can be given any value (or just skipped). It is unimportant. You can use the mouse to choose the center of the view. It will work just like any other graphical coordinate selection. If you just want to move something to the center of the screen, this may be the easiest way to accomplish it. Just point at the location with the mouse, and press the left mouse button. This will move the location you chose to the center of the view. Remember however, that the depth, “into the screen”, will be chosen in the workplane. As described in the previous paragraph, this might not be the point you want to rotate around.

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If you want to center about an existing node or point, you can enable the appropriate snap mode prior to your graphical selection. In this case, the center coordinates will be equal to the coordinates of the entity you “snapped to”. If you really want to specify a three-dimensional center, you may want to use the keyboard. You can choose any of the standard coordinate definition methods, and enter the coordinates manually. You can also graphically select coordinates, and then update one or more of them prior to pressing OK.

Using Center for XY-Plots If you have selected any of the XY-plot styles, View, Center will set both the XY X Range/Grid and XY Y Range/ Grid options to Max Min. The minimum and maximum axes values are adjusted based on the location that you specify. The magnification is unchanged. The location that you choose is just moved to the center of the graph. Instead of the standard coordinate definition dialog boxes, XY-plots display the View Position dialog box. These coordinates are specified as a percentage of the window. The location (0%,0%) is in the upper-left corner of the window. The lower-right corner is (100%,100%). It is usually best to use the mouse to graphically select the new center. This is especially true since the required coordinates are relative to the window and not the graph area.

6.2.8 View, Pan...

Ctrl+P or Alt+F8

... is similar to the View, Center command. It adjusts the position of your model within a view, without changing the magnification or orientation.

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This command provides two different methods to position your model. You can just press the Left, Right, Up, or Down buttons to move your model in the indicated direction. This method moves the amount specified by Percent, which indicates a percent of the window. The other positioning method requires two locations. Within the view, the model is moved from the first location to the second. You will probably find that the easiest method of panning with the second method is to choose the two locations graphically. Point to the location that you want to move from, and press the left mouse button. Then point to the location you want to move to. As you move, you will see an arrow moving with the cursor. The arrow indicates the direction and distance of the pan. You can also pan the view by typing coordinates. The two pan locations are specified in percentages of the window. The location (0%,0%) indicates the upper-left window corner. The lower-right corner is (100%,100%), and the upper-right corner is (100%,0%).

Previewing the Panned View After you define the pan locations, you can press Apply to pan, and redraw the view. This is just like pressing OK, except that the View Pan dialog box is still present. You can still press Cancel to revert to the original view, or you can define additional pan locations to further update the view. If you use the Left, Right, Up, or Down buttons, they will automatically redraw the view.

Rotate, Mag, and Zoom These command buttons are shortcuts to the View Rotate, Magnify, and Zoom commands. If you are updating a view, it is often more convenient to use these buttons, than to press OK and then choose the command from the menu. Pressing any of these buttons automatically accepts any changes you have made - just as if you had pressed OK.

Using Pan for XY-Plots If you have selected any of the XY-plot styles, View Pan will set both the XY X Range/Grid and XY Y Range/Grid options to Max Min. The minimum and maximum axes values are adjusted based on the pan locations that you specify. If you have magnified an XY-plot, this is an easy way to move it around to see different portions of the curves. The pan locations that you choose should be inside the graph area - although it does not have to be. It is usually best to use the mouse to graphically select the pan locations. This is especially true since the required coordinates are relative to the window and not the graph area.

6.2.9 Deleting Views

(Delete, View command)

Views, just like other FEMAP entities, can be deleted from the model. Simply use the Delete View command, and select the number of the views you wish to delete. You may also simply click on a view if it is currently visible to select it. FEMAP will ask if it is OK to delete this view. If you say yes, the view(s) will be deleted. If you say no, the command will be canceled. Views have no entities which are dependent upon them, so they are therefore always deletable. Although it is often times just as easy to de-activate a view than delete it, there are specific instances when deleting a view is recommended. Specifically, if you have trouble working with a view, certain items do not appear, or you get Abort messages, it may be due to a corrupted view (especially if this model had experienced an abnormal termination previously). If you suspect a view is corrupt, simply delete the view and create a new one with the View, New command. You should also then perform a File, Rebuild to restructure the database. This should remove the corruption from the model.

Window Menu Commands

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6.3 Window Menu Commands The commands on this menu control the display of your the different FEMAP windows on your computer monitor, these commands help you to create and manage the graphical windows on your screen. The commands on the Window menu work in conjunction with many of the commands on the View menu, and vice versa, therefore we will often refer to the graphical windows as “view windows”. FEMAP uses the Window menu to place commands to the create, modify, and position FEMAP graphics windows. FEMAP Windows are stored with your model database. They can be either active or inactive. Active view windows are associated with an on-screen window. Inactive view windows are not currently displayed on your screen, but can be activated at any time you choose. The Window menu is separated into five partitions. The first partition involves creating new view windows, making copies of existing view windows, loading currently closed view windows, and closing view windows. The second is contains multiple view window positioning commands, while the third contains a flag to toggle on and off the view window “tabs”. The fourth contains commands to redraw and regenerate the entire view window, as well as highlight specific entities in the active view window. The final portion of the menu holds a list of the views that are currently loaded (up to the ninth view). Each of these areas is described more fully below.

6.3.1 Manipulating Multiple View Windows This section involves creating, sizing, and activating multiple view windows. Each active view window in FEMAP corresponds to a given graphics window which can be sized or changed similar to any standard graphics window. In addition, FEMAP supplies automatic tools for activating, creating, and sizing single or multiple graphics windows (view windows).

6.3.1.1 Window, New Window... ... creates new “tabbed view windows” in your model, and automatically activates them by opening new graphics windows. This command uses the New Window dialog box. Your most basic choice is to select the number of new views and the window layout that you want to create. The dialog box shows you six possible alternatives to create between one and six new views. The pictures show the window layout that will be created. Each rectangle represents a window that will be created. The black (or darkest) rectangle indicates the graphics window which will initially be active.

If the Default View option is chosen, when new views are created, the view options and selections will be set to match those of the default view. This is the view that is created automatically when you start FEMAP with an unnamed model. If Copy View is chosen, the new views are created to match the view that you select from the list. Whenever you create multiple views, the orientation of the views is automatically defined to provide multiple planes (XY, YZ, and ZX) and isometric views. The view represented by the black rectangle is always set to an XY

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view if you use the Default View option, or to the orientation of the view that you are copying if Default View is off. The following table shows the orientations of the views which are created for each layout. Layout 1

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Use Open View(s) to open existing views that have been closed using the Window, Close command, Close on the drop-down menu from the view tab, or the “X” in the upper right hand corner of the graphics window area. Choose a view from the list of existing views, then click OK to open a view. If you would like to open multiple views at one time, there are two separate methods: 1. You can hold the Ctrl key down to select each view from the list individually OR 2. You can hold the Shift button down and select a “range of views” to open by selecting a “first view” and the “last view” of the range, which will highlight all the views you want to open at once. The ID and Title are used to set the ID and view title for the window represented by the black rectangle. View titles are displayed in the title bar of the window. Titles are automatically assigned to the other views in any multi-view layout that you create. These automatic titles describe the view orientation. When the Close Existing Windows check box is checked, it will close all existing graphics windows and deactivate the associated views once the OK button is pressed. You need to check this box before you press OK, if you want the new views to be the only ones which are active.

6.3.1.2 Window, Close ... This command closes the active view. If you try to close the last remaining open view of a model (or if there is only one view currently open), FEMAP will ask if you want to save your model at that time.

6.3.1.3 Window, Tile Horizontal ... resizes and arranges all of the active graphics windows to fit horizontally in the FEMAP workspace. The windows are arranged so that the contents of each window are visible, and so that no windows overlap. The current size and position of the FEMAP main window, and the FEMAP Messages window combine to determine the overall area that Window, Tile Horizontal can use. Tile uses the largest available rectangular area which is inside the main window and which is not obscured by the Messages window, other Dockable Panes (Entity Editor, Model Tree, and Data Table), or the toolbars. If you do not change any of these, and only have one graphics window, Window, Tile Horizontal will restore it to the size and position of the default graphics window. If you reposition or resize/reshape the Messages window, you can use Window, Tile Horizontal to automatically make your graphics windows as large as possible without having any overlapping windows. In general, overlapping windows are not desirable since they can cause additional redrawing to reveal obscured information. To make a view the active view, you can either click inside the window or click the corresponding tab at the top of the graphics window (if Window, Toggle Tabs flag is turned on)

Window, Tile Vertical

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6.3.1.4 Window, Tile Vertical resizes and arranges all of the active graphics windows to fit horizontally in the FEMAP workspace. The windows are arranged so that the contents of each window are visible, and so that no windows overlap. The current size and position of the FEMAP main window, and the FEMAP Messages window combine to determine the overall area that Window, Tile Vertical can use. Tile uses the largest available rectangular area which is inside the main window and which is not obscured by the Messages window, other Dockable Panes (Entity Editor, Model Tree, and Data Table), or the toolbars. If you do not change any of these, and only have one graphics window, Window, Tile Vertical will restore it to the size and position of the default graphics window. If you reposition or resize/reshape the Messages window, you can use Window, Tile Vertical to automatically make your graphics windows as large as possible without having any overlapping windows. In general, overlapping windows are not desirable since they can cause additional redrawing to reveal obscured information. To make a view the active view, you can either click inside the window or click the corresponding tab at the top of the graphics window (if Window, Toggle Tabs flag is turned on)

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6.3.1.5 Window, Cascade ... resizes and arranges all of the active graphics windows to fit in the FEMAP workspace. The windows are arranged starting in the upper left corner of the main window workspace. Each window's title remains visible, so that you can identify the active windows, but only one graphics window will be fully visible. Like the Tile commands Window, Cascade chooses the available area as the largest rectangular area within the main window that is not obscured by the Messages window, other Dockable Panes (Entity Editor, Model Tree, and Data Table), or the toolbars. Window, Cascade is only available when you have multiple active graphics windows. Cascading windows are not generally recommended since they can result in additional redrawing of the graphics windows.

6.3.1.6 Window, Toggle Tabs ... toggles the view window “tabs” on and off. You can move from view window to view window by clicking the tabs. You can also position the curser over any view window tab and click the right mouse button to select from a helpful “context sensitive” menu which allows you to access the View, Create/Manage; Window, New; and Window, Close commands, as well as, change the color of the tab and toggle the tabs on and off. When the view window tabs are visible, the tabs show the current view window name. If multiple models are open they show the model name and then the view name in the following convention: Model Name : View Name

6.3.1.7 Window, Toggle Title Bars ... only available when multiple views are open in FEMAP. Toggles the “Title Bars” in ALL views on and off. This can be very helpful when trying to show multiple views at once because it saves space on screen in each view.

6.3.2 Redrawing Windows This section includes commands for redrawing of your model. There are two different commands for redrawing: Window, Redraw and Window, Regenerate. In addition, you can show particular entities in a view, as well as apply all changes to all views of the active model using View, All Views.

6.3.2.1 Window, Redraw...

Ctrl+D or F12

... forces FEMAP to redraw or redisplay the active graphics window. You can redraw your graphics at any time. Graphics windows are redrawn automatically whenever required by Windows. Additionally, if you select the Autoplot option under the File, Preferences, Views command, all entities that are created or modified will be drawn automatically. This option is on by default. Unlike Window, Redraw, the Autoplot option only draws entities you created or modified, not the full view. For more information, see 6.1.1.2 Section “Window, Regenerate”

Redrawing Multiple Windows

Ctrl+Shift+D If you have multiple graphics windows on your screen, and All Views is set, they will all be redrawn. In addition, no matter how All Views is set, you can redraw all active windows by pressing Ctrl+Shift+D. For more information, see Section 6.1.2, "View, All Views...".

Aborting a Redraw Drawing your model can take a significant amount of time, depending on the size of your model and the options you choose. In some cases, you may not want to wait for the view to be completely redrawn before you choose your next command. In these cases, you can abort the display simply by choosing your next command.

Window, Regenerate...

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When FEMAP is redrawing your display, the graphics cursor will change to an hourglass behind a pointer. This shape indicates that FEMAP is busy with your current command, but the current command will be aborted automatically if you make a new selection. Actually, FEMAP just “watches” the keyboard and mouse. The command is aborted whenever you press any key, or mouse button. These are the actions that you have to do to choose the next command anyway. When FEMAP is done with the current command, the hourglass will disappear and the cursor will return to its normal pointer or crosshair shape. Since FEMAP automatically aborts whenever you press a key or the left mouse button, you can never press either of them before a redraw is complete, unless you want to abort. If you abort a redraw, you should still be able to graphically select any of the entities which have been displayed. You may not be able to select entities which have not been displayed. Extensive graphical selections should always be done in a view which has been completely redrawn.

6.3.2.2 Window, Regenerate...

Ctrl+G or Ctrl+F12

... is just like the Window, Redraw command. It forces FEMAP to redraw either the active graphics window, or all graphics windows (if All Views is set). When FEMAP draws your model for the first time, certain view dependent data is retained in your model. Saving this data speeds up future redraws. For all types of displays, FEMAP will save a display list of transformed coordinates. This eliminates the need to continually transform from your three-dimensional model, to the orientation you choose on the two-dimensional screen. For hidden line displays, FEMAP also saves a sorted list of the entities which you displayed. Once this list has been calculated, it can be redisplayed without additional hidden line calculations. Similarly, for free edge and free face displays, lists of the free edges and faces are retained. If you are using the Quick Display capability, even more information is saved. If you choose the Window, Redraw command, these saved lists will be used, whenever they are available. Window, Regenerate will throw away all of the lists and then call Window, Redraw. This forces FEMAP to regenerate all of the information from your model. If the display lists were never created, Window, Redraw and Window, Regenerate are identical. FEMAP will automatically discard the display lists whenever you change alignment or close/deactivate a view. FEMAP will also update the transformed coordinates whenever you move a node or point. FEMAP will not update or destroy the hidden line or free edge display lists, since rebuilding them involves significant computations. It is up to you to choose the Window, Regenerate command whenever you want FEMAP to calculate a new hidden line or free edge display. Conversely, for many modifications (zoom, pan, color, layer, small position changes...) you can still choose Window, Redraw and save a large portion of the time required for these displays.

Regenerating Multiple Windows

Ctrl+Shift+G If you have multiple graphics windows on your screen, and All Views is set, they will all be regenerated. In addition, no matter how All Views is set, you can regenerate all active windows by pressing Ctrl+Shift+G.

Hint:

If you are redrawing your model and something does not look correct, always try to do a regenerate before looking for other problems.

6.3.2.3 Window, Show Entities...

Shift+F12

... provides a way to graphically query your model. Although there are many possible uses for this command, there are two primary reasons you might want to choose it: What is the ID of this element (or node...)? The first potential use occurs if you have a model displayed on the screen with no labels (because the picture is too complicated with them). You can choose Window, Show Entities and graphically pick one or more entities. With the labelling option turned on, FEMAP will display the IDs of the entities that you choose. Where is element (or node...) number 10? The second use involves finding certain entities in a complicated model. If you need to find a certain entity, you can just type its ID, rather than selecting it graphically. FEMAP will highlight the entities that you have chosen and

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optionally add labels. If you autoscale your model before using this command, the entity will be visible on your screen. Selecting Options The Window, Show Entities command requires input of the type of entity to show. You can only select one type of entity each time you use this command. Style If you select Erase Background First, the window will be erased before the selected entities are shown, otherwise the entities will just be added to the current picture. Transparent Highlight will highlight the selected entities, but will make all non-selected entities temporarily transparent as well. Note: The level of transparency used in the Transparent Highlight option can be adjusted using a global value for all entities using View, Options; Category: Tools and View Style; “Transparency” option. The Label with ID option controls whether IDs will be added to the selected entities. If entity labels are already on, they will be drawn even if this option is off. If they are normally off however, turning this option on insures that the entities that you show will be labelled with their ID. Turning Show Normals on will show the element normals for the selected elements. By default, Show Color is selected. This will cause all selected entities to be drawn in the color listed to the right. You can change this color by typing a different ID, or by pressing Palette to choose a color from the palette dialog. The default show color has been chosen to highlight the entities that you choose. If you just want to add IDs to the selected entities, you may want to switch to entity colors. This will display the entities in their normal colors. Selecting the Entities to Show After you choose the desired options, and press OK, you will see the standard entity selection dialog box. The type of entities that are selected by this box depends on the entity type option that you chose. Just like other commands, you can use any combination of keyboard and graphical input to select the entities that you want to show. Press OK to show the entities that you have selected. Hint:

The Window, Show Entities command is also very useful to show connections between FEA entities and geometry. For example, to see what nodes are attached to a surface, select Node as the option. When the standard entity selection dialog box appears, change the method to On Surface, and select the desired surface. FEMAP will then highlight all nodes that are attached to that surface.

6.3.2.4 Window, Open Views - 1,2,3,4,5,6,7,8,9 The nine most recently opened views are listed on the bottom of the Window menu. If there are multiple models open in the same FEMAP session, they are listed using a “number model name : view name” convention. For example: 1 Wing.MODFEM : Stringers.

6.4 Groups and Layers The previous section concentrated on the View menu command to manipulate the view. The other major area to modify what you see in a view involves groups and layers. By using groups and layers, you can segment your model into smaller, more manageable, discrete pieces. These pieces can then be used to minimize the amount of information presented in the view window, or in printed reports by specifying which group(s) will be seen or used to create a report. Groups and layers also make it easier to manipulate, update, and apply loads to your model. This section will describe the differences between groups and layers, commands pertaining to layering, which are scattered throughout the FEMAP menu, and the Group menu.

Differences Between Groups and Layers

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6.4.1 Differences Between Groups and Layers Groups and layers provide a convenient method of segmenting a model, however, there are some key differences between groups and layers. Some main points about groups and layers are summarized in the table below. Groups

Layers

Entity in multiple groups

Each entity on only one layer

Any combination of groups, the Active group only, or a selected group

Any combination of layers

Display Active

Only one active group

Only one active layer

Reference

By creating multiple groups, and using multiple layers, you can create an infinite number of visual combinations for your model. This greater flexibility also provides the disadvantage of more methods to “hide” things in your model. If you do not see an entity which you created, it is a good bet that either it is not in the group(s) you are currently displaying, or it is not on a visible layer. Groups are designed to mimic how FEA models were numbered and arranged when they were built by hand. For example, in the aircraft industry, a model of a complete aircraft would be carefully numbered. All the nodes and elements at a frame at a particular location along the fuselage would be numbered in such a manner as to clearly identify them as belonging to that frame. FEMAP grouping makes it very easy to isolate portions of a finite element model that are numbered in such a manner. You may also easily group elements using a particular property or material, by element type, attached to solid geometry, or currently on a particular layer. Layers, on the other hand, are designed similar to layering in most CAD systems. The name layer comes from the clear sheet of paper analogy for CAD layering, where all the entities associated with a given layer would be drawn on a clear sheet of paper, and only the “active” clear sheets being overlaid would produce a visual image.

6.4.2 Layer Commands There are several commands associated with layers which are scattered through the FEMAP menu. They can be separated into two major areas: creating a layer and viewing layers, which are discussed below. Other commands involve deleting layers, modifying layer reference on entities, and the Group, Layers command. Brief explanations are also provided for these entities.

6.4.2.1 Creating a Layer (Tools, Layers command) The Tools, Layers command is used to define layers in your model. By themselves, layers cannot be displayed. Rather, all entities in FEMAP are placed on the layers that you create with this command. See Section 7.4.3.2, "Tools, Layers..." for more information.

6.4.2.2 Viewing Layers (View, Visibility... command) The Layer tab of the View, Visibility command or the “visibility check boxes” for Layers in the Modal Info tree allows you to control which layers are active for the display. You may View All Layers (default setting) or View Multiple Layers. You may “check” any number of layers to make them visible. For more information, see the Layers tab portion of Section 6.1.4, "View, Visibility...".

6.4.2.3 Related Layer Commands Other commands related to layers include the Modify, Layer menu, Delete, Tools, Layers, and Group, Layers. Each of these commands are described in more detail in their appropriate sections. A brief description, however, is provided below.

Modify, Layer The Modify, Layer commands actually make no changes to the layers themselves. Instead, you can use these commands to move entities from one layer to another. This is a much easier method of changing the layer of a large number of entities in comparison to Modify, Edit, which requires input for each entity you selected. See Section

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3.6.3.3, "Modify, Layer Commands" for geometry and Section 4.8.2.4, "Modify, Layer Menu" for finite element entities.

Delete, Tools, Layer This command enables you to delete a layer. You will typically only want to use this command when you have an empty layer. This command does not delete entities that are on the layer. In fact, these entities may still have the same layer reference, but the layer itself will be removed. The entities on the deleted layers will then not be visible unless you have Show All Layers active. There are also no checks made to see if entities exist on a layer when you are about to delete it. Therefore, be careful when using this command. Hint:

If you do delete a layer which has information contained on it, you may simply use Tools, Layers to create a new layer with that same number. The entities which were on the deleted layer will automatically be placed on the new layer.

Group, Layers This command provides an easy method to limit a group to a specific number of layer(s). This does not automatically create a group with all the entities in that layer. It simply limits the selected entities to a specific layer. For more information, see Section 6.4.3.4, "Group, Layers...".

6.4.3 Group Menu Commands The commands on this menu allow you to create, edit, and manipulate groups within your model. These commands are separated into three major sections: •

the Group, Create/Manage command



group manipulations



commands to add certain identities to the group

How Groups are Used FEMAP groups identify portions of your model. Using the Group tab of the View, Visibility command, you can choose Show Active Group, Show Selected Group, or Show/Hide Multiple Groups that will be used to limit your display to the portion of the model which is “in the group(s)”. In addition to simplifying your display, this group also has an impact on postprocessing. Contour/criteria limits can automatically be adjusted to the peak values which occur on those entities in the group(s) (see Section 6.1.5.3, "View, Options..."). Similarly, nodal output data is converted to elemental output data, and vice versa based on the selected group(s) (see Section , "To use this option, follow the general steps in "Performing Operations on Output Sets and Vectors"."). Individual commands on the Group menu are explored in Section 6.4.3.2, "Group, Operations Menu", Section 6.4.3.3, "Group Clipping Menu", and Section 6.4.3.5, "Grouping Individual Entities". For deleting and renumbering groups see Section 6.4.4, "Deleting Groups (Delete, Group command)" and Section 6.4.5, "Renumbering Groups"

6.4.3.1 Group, Create/Manage...

Alt+F2

... displays the Group Manager dialog box which may be used to create a new group, update existing group Titles or IDs, delete a single group or all groups, and define “Referenced Groups”. It is somewhat similar to the Model, Load, Create/Manage Set and Model, Constraint, Create/Manage Set commands. The concept of Referenced Groups allows an existing group to “reference” other existing groups in your model (essentially, create a “Group of Groups”). A group which “references” other groups may also contain any number of additional entities. Once a group is referencing other groups, the icon will change in the Group Manager dialog box. Groups which reference other groups may also be referenced by any other group.

Group, Create/Manage...

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Create new Group

Regular Group icon

Update the title of an existing Group Renumber highlighted Constraint Set Delete highlighted Group Delete all Groups Define Referenced Group Deactivate All Groups

Group containing Referenced Groups icon

Title Filter

Clear Title Filter

To create a new group, click the New Group button. In the New Group dialog box, enter a descriptive Title, then press OK to return to the Group Manager or More to create another new group. All group definition commands work with the active group. To activate a group that already exists, simply choose it from the Available Group Selected Group is Active list. Once a group is highlighted in the list, the Update Title, Renumber, and Delete options become available. To delete all groups, click Delete All or deactivate all groups, simply press None Active. The Referenced Groups button will display the Referenced Groups dialog box:

The Referenced Groups for Group drop-down list may be used to select any existing group. Any number of groups may be moved between the Available Groups list and Referenced Groups list for a particular group by highlighting the groups in the appropriate list and pressing the Add or Remove buttons. Remove All will move all groups from Referenced Groups to Available Groups. When a group which references other groups is added to the Referenced Groups list, the referenced groups will be listed in a “tree structure” beneath that group (Shown above)

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. Note:

If Group “A” is referenced by Group “E” and Group “F” and both groups “E” and “F” are then referenced by another group, Group “G”, Group “A” will only appear once in the Referenced Groups list. All other instances of Group “A” will be shown using a red “X” in the middle of group brackets.

6.4.3.2 Group, Operations Menu The commands on this menu are used to manipulate a group. They do not add any new definitions to the current group.

Group, Operations, Evaluate... ... evaluates any number of selected groups. When you invoke this command, FEMAP brings up a dialog box which allows you to select any number of groups by highlighting them using windows standard methods for multiselection (holding CTRL down for selecting multiple entities one at a time or hold SHIFT to select a Range of entities). Once the desired groups are highlighted, click OK and no more user input is required. Your groups will now contain all entities which satisfy the rules of the group. You should use this command any time that you create or modify entities that should be selected in the current group. This command will use the group clipping planes, layer options, and rules to find the entities that are included.

Group, Operations, Automatic Add... ...automatically adds all newly created entities to the selected group. With this option there is no need to reevaluate the selected group to have the entities appear - they are added without the need for reevaluation.

Note:

You will be able to choose from the “Active” group, Select a group or None. The default is None, which means that new entities will not be added into any group. If you choose the Active option, newly created entities will be added to whatever group is active at that time. You can change the active group using the Group, Create/Manage command. If no group is active, it is the same as choosing the None option. If you choose Select, then you must also choose an existing group from the combo box. All entities will be added to that group. In this mode, if you want to switch to a different group, you must use this command to make a new selection.

Note:

In File, Preferences, the Views, Autoplot Created/Modified Geometry preference must be on, or Automatic Add will be disabled.

Group, Operations, Evaluate Always... ... allows you to set up any number of selected groups to be evaluated every time they are used. By default, the active group will be highlighted in the multi-select dialog box. When this option is set for the active group, the icon next to the command in the menu will turn orange. Once the selection of groups has been completed, a question will appear asking “OK to evaluate selected groups every time they are used?”. If you choose Yes to “always” evaluate, every time you use the group, FEMAP will reevaluate all clipping, layers, and rules. You do not have to use the Group, Operations, Evaluate command. This can significantly decrease system performance, but will automatically add new or modified entities to the group every time you use it. You can turn this option off by reselecting the command, and choosing No - don't automatically evaluate. You do not need to turn on Evaluate Always for a group that you select for Automatic Add. In fact, it will be much faster if you do not. Note:

If you are displaying a group where you have turned on Evaluate Always, you will not be able to graphically select nodes or other entities in that view. In addition, any attempt to reference that view will be significantly slower than if Evaluate Always was off, because the group must be reevaluated.

Group, Operations Menu

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Group, Operations, Renumber Rules... ...provides the capability to maintain the same entities in the group even when you renumber the entities. When you select this command, a multi-select dialog box will be displayed with only the Active Group highlighted (default). You may also highlight any other group(s) from the list. Once the selection of groups has been completed, a question will appear asking “OK to Renumber selected Group(s) when Entities are renumbered?”. If you select Yes, “renumber rules” will be turned on for the selected group(s). This means that if you have included Node 1 in a group, then you renumber it to 50, it will still remain in the group (i.e. FEMAP will change the Group Node ID entry from 1 to 50). If you select No, “renumber rules” will be turned off for the selected group(s). This means Node 1 will remain as the entry in the group and you will lose the new Node 50 (renumbered Node 1) from the group. Any entity you make in the future with Node ID 1 will automatically be included in the group. You will typically want to have this option on Yes to prevent changes in your groups from renumbering. Note:

When “Renumbering Rules” for the Active Group are “on”, the background of the icon will be orange.

Group, Operations, Copy... ... makes a new group which is a copy of the selected group. When you invoke this command, you may input an ID and title of the new group that will be created. If the active group has not been evaluated since it was created or last modified, FEMAP will always evaluate it before the group is copied. There is also an option to Condense New Group, which will create a copy of the active group based on “ID rules Only”, not based on rules, clipping, and layer information. See “Group, Operations, Condense...” for more information about condensing groups.

Group, Operations, Condense... ... allows you to select any number of groups to “condense” to be “ID Rules Only” groups containing only the entities currently in the group, instead of based on rules, clipping, and layer information. The new ID rules (coordinate system IDs, point IDs, node IDs, etc.) will select all of the entities that were previously selected in the group. It does not matter if the original groups were created using clipping or other types of rules; the selections will be converted to ID rules, as these rules will be removed from the “condensed” group. When to Use Condense Condense is usually used when you have defined a group using clipping or other fairly general rules (like Nodes 1 to 10000), and you want to make sure that no entities, other than those which are currently selected, will be inadvertently included during future group evaluations. In addition, a condensed group will typically reevaluate faster than the group defined by clipping. Condense will reduce these general selections to specific rules which will only include the currently selected entities.

Group, Operations, Reset Rules... ... deletes all rules in the active group. You can selectively delete rules by choosing the appropriate Group menu commands and deleting entries in the standard entity selection dialog boxes. If you want to delete all of your rules, of all types, this command is much faster. As for all delete commands, you will be asked to confirm your desire to delete the rules before this command proceeds.

Group, Operations, Booleans... ... creates a new group from a selected set of existing groups based on a chosen “boolean” operation. The Group to Create portion of the dialog box allows you to choose the ID for the new group and give it a Title. If you do not specify a Title, FEMAP will create one based on the IDs of the Groups AND the Operation used to create the new group. For example, if you are using the Add/Combine operation and have selected groups 1, 3, and 5, the default Title would be “Add 1, 3, 5”.

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Multiple groups can be chosen from the “Select One or More Groups from the List to Process” list in the Groups to Process portion of the dialog box using windows standard selection methods. Holding down the Ctrl key and clicking in the “list” allows you to choose multiple groups one at a time. Holding down the Shift key while clicking in the “list” allows you to choose a “range” of groups. There are six choices in the Operation section of the dialog box. Here is a brief description of each operation: Note:

The “Base Model” for all of the “Examples” in this section is a simple 9 element “high” by 7 element “wide” rectangle. Only elements are in the groups being processed with the various boolean operations.

Add/Combine – Creates a new group by adding multiple groups together. For example:

+

=

Subtract – Creates a new group by subtracting any number of groups from a Single selected group.

Note:

When the Subtract operation is chosen, the Subtract From drop-down list in the Groups to Process portion of the dialog box will become available. The group chosen in the Subtract From drop-down list is the “base group” and all of the groups chosen in the “list” will be subtracted from the “base group”.

Group, Operations Menu

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For Example:

-

=

In All – Creates a new group that contains entities which are in ALL of the selected groups (i.e., if element 1 is in group A AND Group B, element 1 WILL BE in group C). Another way to think of it is that only entities which are “common” to ALL the selected groups will be in the new group. For Example:

IN ALL

=

Elements “Common” to Both Groups in New Group

Only in One – Creates a new group that contains entities which are ONLY in one of the selected groups (i.e., if element 1 is in both group A AND Group B, element 1 will NOT be in group C). Another way to think of it is that only “unique” entities will be placed into the new group. For Example: Elements “Unique” to Each Group in New Group

Only in One

=

Not in Any – Creates a new group that contains entities which are NOT in ANY of the selected groups, but are in the rest of the model (i.e., If elements 1-10 are NOT in Group A and NOT in Group B, they WILL BE IN Group C). Note:

When using the Not in Any operation, only entity types that are in at least one of the “Base Groups” will be in the new group that is created from entities NOT in the “Base Groups”. For example, start with a model containing 100 nodes, 81 elements: If Group A contains “n” elements and zero nodes, then Group B will only contain the “81-n” elements that are NOT in Group A. If Group A contains “n” elements and “n” nodes, then Group B will contain the “81-n” elements and the “100-n” nodes that are NOT in Group A.

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For Example:

Not in Any

= Elements NOT in either Group in New Group

Not in All - Creates a new group that contains entities which are NOT in ALL of the selected groups (i.e., If elements 1-10 are in Group A, but not in Group B and Group C, they WILL BE IN Group D). This command is only useful when three or more groups are being processed. Only entities “Common” to ALL selected groups will NOT be in the new group. If you use this command with only two groups, it will create the same group as Only in One.

Group, Operations, Add Related Entities... ... when this command is used, ALL other entities that are somehow related to the entities currently in a selected Group will then be added to that Group. For instance, if a group contains only elements, using this command would add all nodes, properties, and materials used by those elements to the group. In addition, any loads or constraints associated with the elements or their nodes would also be placed in the group. In this case, nodal loads, elemental loads, nodal constraints, and constraint equations would be added to the group. Also, if the elements in the group happen to be laminates, then any layup used by the laminates would also be added to the group.

Group, Operations, Generate... ... will automatically create groups by segmenting your model based on geometric, property and material features and discontinuities. The capabilities of this command are also used by the Model, Output, Extrapolate command to segment your model prior to extrapolation. In that case however no groups are created. When you choose this command, you will be asked for the elements that you want to consider. This command only works with planar or solid elements. Line and other types of elements will simply be ignored. Typically, you should only choose one type (planar or solid) at a time. You will then see the following dialog box: The correct element type should be selected automatically based on the elements that you selected - unless you chose multiple types. You must then decide how you want to segment your model. Add Layers If you turn this option on, not only will elements be placed into segmented groups, their layers will also be updated so that each segment is on a separate layer. This can be useful if you want to display multiple segments simultaneously, since any combination of layers can be displayed. Attribute Breaks Breaking your model into segments based on attributes allows you to find areas of differing thickness or material. When used for output extrapolation, these options recognize that stresses or other output are not continuous across different materials or other part/thickness boundaries. If you want to put elements with different properties into different groups, choose Property ID. Since each property references a material, this will automatically put each material into one or more groups. If you just want to break based on changing materials, choose Material ID. Choose None to skip this type of checking when the model is being segmented.

Group, Operations Menu

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In addition to these basic attribute options, you can also choose to formulate different groups based on changes in the layer or color that each element references. These options really provide you a way to customize the way that FEMAP will segment your model. For example, if you really want to break some portion of your model into multiple parts, but all elements have the same property, you can always set their color or layer prior to using this command, then choose the appropriate option, and FEMAP will segment based on those attributes. Geometric Breaks Unlike the attribute breaks, which can be used with either planar or solid elements, geometric breaks apply only to planar elements. Geometric breaks are very important for segmenting complex plate structures. For example, if you have a box structure, geometric breaks will automatically detect and segment each face of the box - even if all elements have identical attributes. When you choose to do geometric breaking, FEMAP calculates the normal to the planar face for each element. If the normals of two adjoining elements are within the angle that you specify of being parallel, they will be considered to be in the same segment (neglecting any attribute differences). If they are not within that angle, a new segment will be formed. If the “Matching Normals Only” option is off, then the direction of the normal vector is not considered when doing this comparison - two coplanar elements with reversed normals will not generate a break. If the option is on, then the normal direction is considered and reversed normals will usually cause breaks. To ignore geometric breaks, choose None.

Complete Model

Generated Groups

Note:

This command can create quite a few groups given a large model - especially if you use geometric breaks with a small angle. It can also take quite a while to evaluate the entire model.

Note:

Since FEMAP has no way of knowing what the various segments of your model represent, it simply assigns default titles to the groups that are generated. After they are created, it is usually best to display each group, one at a time, and change the title (use Group, Create/Manage) to something that will be more meaningful to you.

Group, Operations, Generate Solids... ...will automatically create groups based on solid geometry. You simply select the solids you wish to group and FEMAP will create one or more groups containing the selected solids and their associated curves, lines and points. If you select “Create Multiple Groups”, then one group will be created for each solid that you selected. If not, then one group will be created containing all of the solids. If you select “Include Mesh, Loads and Constraints”, then these entities which are associated with the solids will also be included in the groups along with the geometry.

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The default for this command is Create New Groups, which will create new groups based on the selected Generation Options. In addition, Move to New Layers will move the entities for each new group to a new layer. Finally, you can have FEMAP only create new layers and move entities for the selected solids onto them instead of creating new groups and new layers, by turning OFF the Create New Groups option and turning on Move to New Layers. . .

Operations, Generate Property... ... will automatically create a single group or a number of separate groups in your model based on properties. You simply select the properties you wish to consider, then FEMAP will prompt you with a question: “Ok to Make a Group for each Selected Property (No=One Group for All)?”. Answering Yes will create separate groups containing elements that reference each property, while answering No will create one group for all of the selected properties. This works very similar to Group, Operations, Generate, except you pick the particular properties for the groups, and no discontinuities will be considered. All elements in the model referencing a particular property will be placed in the same group, regardless of their locations

Group, Operations, Generate Material... ... is similar to the Group, Operations, Generate Property command, except the single group or separate groups for each material are generated based upon the materials of the elements (on their property cards), not the properties.

Group, Operations, Generate Elem Type... ...is similar to the Group, Operations, Generate Property command, except the single group or separate groups for each element type are generated based upon the element type, not the properties themselves.

Group, Operations, Generate With Output... ...automatically creates a group by selecting nodes or elements that reference analysis output that meet one or more specified criteria. When you choose this command, you will be asked to select the Output Sets that contain the results that you want to consider. Only results in these sets will be considered when deciding whether a specific node or element meets the selection criteria. When you press OK, you will see another dialog box, that allows you to specify the selection criteria.

Group, Operations Menu

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The options on the left side of this dialog let you specify the criteria that will be used to evaluate the results you choose. Only criteria that you add to the Specified Selection Criteria list (using the Add Criteria button) will actually be used. Note:

If the Specified Selection Criteria list is too small to see the entire criteria, you can drag the corner of the dialog box, or press the icon at the right side of the toolbar to make the box, and the list bigger.

Note:

You can currently define up to 125 simultaneous criteria. This does not include the output vectors that are checked with the Include Components/Corners or Include All Layers options.

Output Sets These options let you choose the Output Sets to consider for this criteria. As you remember, you selected a list of Output Sets in the previous dialog box. If you choose Any Set, then results from each of those sets will be evaluated for each node/element, and if any of the results meets the criteria, then that node/element will be selected. If you choose All Sets, then results in every selected set must meet the criteria for the node/element to be selected. Again, both of these options only refer to all of the sets that you selected, not necessarily all of the output in your model. If you choose Set, you must select the single Output Set that you want to consider from the list. In this case, and only this case, the set you choose does not have to be one of the originally selected sets. Output Vectors From the From list, you must select the output that you want to use to select your nodes/elements. The vectors that are available in this list change depending on the setting of the Entity Selection options. Normally, you will want to simply select a From vector, and leave Thru set to None. This will result in one criteria being added to the list, using the vector you select. If however, you want to use the exact same criteria for an entire range of vectors you can choose a Thru vector. When you Add this criteria, you will actually see one criteria for each vector in this range. Include Components / Corners When you select an output vector, you may want to consider associated results as well. If this option is off, only the single output value in the vector you choose will be used. If it is on, however, associated component or corner output will also be compared. If any of these associated values, or the value of the vector you chose, meets the criteria, then the node/element will be selected. Some examples of this include: You select...

If “Include Components” is on...

...“Total Translation” or other “Total” nodal output ...output at the centroid of a plate or solid element ...output at one end of a beam

...the “Total” vector, and the X, Y and Z Component vectors will all be evaluated ...the centroidal vector will be evaluated, as well as, the output at all of the element corners. ...similar output at both ends of the beam will be evaluated (Note: picking output at one stress recovery location will not automatically evaluate the other stress recovery locations on a beam - those must be specified as individual criteria - possibly using the Thru option)

Include All Layers This option is for use with results on plate or laminate elements. If it is off, then only the vector you select will be evaluated. If it is on however, then similar results from all layers of that element will be evaluated, and if any meet the criteria, then that element will be selected. For plate elements, this means no matter which output you select, results from the Top, Middle, and Bottom locations (if available) will be evaluated. For laminate elements, no matter which ply you select, all plys will be checked. Selection Criteria These options provide the basis on which output values are evaluated. You can compare the values to see if they are Above a Minimum, Below a Maximum, or Between or Outside the Minimum and Maximum. In the last two options, the minimum must always be less than the maximum. Entity Selection You can choose to select either Nodes or Elements with these options. When you change these options, the available output vectors in the lists change to only show the results for the selected type. In addition, whichever option

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you choose also represents the entities that will be selected into the Group you are defining. These options are only available when you are defining a Group. If you get to this dialog box from the Pick method in the Entity Selection dialog box, then either Nodes or Elements will automatically be selected, depending on the entity type that you are selecting. Select If These options allow you to build very powerful combinations of multiple criteria, however they can be somewhat confusing. Lets look at the simple case of two criteria. If you choose All Criteria Met (And), then when the two criteria are evaluated, both criteria must be met for the node/element to be selected. The And refers to the following syntax - if criteria 1 AND criteria 2 are met, then the entity will be selected. On the other hand, if you choose This Criteria Met (Or), then if either criteria is met, the node/element will be selected. Again from a syntax standpoint if criteria 1 OR criteria 2 is met, then the entity will be selected. Normally, you will want to choose one of these methods when you start to define criteria and leave it set - this will result in either requiring all criteria to be met (And), or any one of the specified criteria being met (Or) for the nodes/elements to be selected. By changing these settings as you define criteria however you can build more complicated relationships. To do this successfully however, you need to understand that FEMAP evaluates criteria, and these options in a sequential fashion, starting at the beginning of your list. Shown with parentheses to help to indicate the order of operations, this could be described as: (((((1 And/Or 2) And/Or 3) And/Or 4) And/Or 5) And/Or...) where the numbers represent the various criteria you specify, and “And/Or” can be either one of the Select If options. As you can see, if you are varying these options, the overall process is order dependent, so you will want to think about this before defining your criteria. Title When you are defining a Group, this allows you to specify a meaningful title for the Group that will be created. Add Criteria Press this to add the options you have defined on the left to the Specified Selection Criteria list. Update When you click on an item in the Specified Selection Criteria list, the values corresponding to that entry will be loaded into the left of the dialog box. You can then change the values and update that entry by pressing this button. The Thru option will be ignored when you use this button since it really generates multiple criteria, not the single one that you are updating. Delete and Reset To remove a criteria that you have added to the Specified Selection Criteria list, click on the item in the list, and press Delete. To remove all of your defined criteria, press Reset.

Group, Operations, Generate Superelements... ...is similar to the Group, Operations, Generate Property command, except the groups are based upon the Superelement ID of each node. Because only nodes have any type of Superelement Identification, you will notice that only elements with ALL nodes being of a particular Superelement ID will be in the group generated for that Superelement ID. If an element has nodes from two different Superelement IDs, and one of the Superelement IDs is 0 (Residual Structure), that Element will be placed in the “Residual Structure” group. On the other hand, if an element has nodes from two different Superelement IDs, and one of the Superelement IDs is NOT 0, that element will not appear in any of the generated groups.

Group, Operations, Generate Entities on Layers... ...is used to generate an individual group for each layer in the model which has been selected. Each generated group will contain ALL entities on a specific layer. You will be asked if you would like to “Condense” the new groups or not. See Group, Operations, Condense for more information.

Group, Operations Menu

Note:

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This command is a great way to be able to list all of the entities on a specific layer. Simply run this command, choose a layer or layers, then use List, Group command and check the List All Entities in Group option.

Group, Operations, Move to Layer... ... is used to move all entities in a selected group or groups to a single selected layer. If an entity is in multiple groups, the entity will be moved to the layer which has most recently had a group containing the entity moved onto it with this command. For example, element 5 resides in both “Group 1” and “Group 2”. If the entities in “Group 1” are moved to “Layer 2” with this command, element 5 will be moved to “Layer 2”. If this command is used again to move the entities in “Group 2” to “Layer 3”, then element 5 would also be moved to “Layer 3”, because it was in the group that was most recently moved to a layer.

Group, Operations, Peel... ... is used with solid elements to remove one or more layers from the outside of a model. Initially, you choose the elements that you want to “peel”. Typically you will want to select the entire model. Remember however, that only solid elements are considered for this command. You specify the number of layers of elements to “peel” off of the outside. Elements are “peeled” if they have one or more faces on the outer surface of the selected elements. Similarly if you choose to peel multiple layers, each layer is removed, and the next layer is “peeled” from the remaining elements. You have two choices as you group elements using this command. You can create groups from the outer layers - the ones that are “peeled”. This will result in one group for each layer that you choose. You can also choose to create a group from the elements that remain after all peeling has been completed - i.e. the core elements. While it is somewhat difficult to visualize the result of this command the following picture attempts to show it: First Layer (no center elements)

Complete Model

Second Layer (no center element)

Remaining Core

Group, Operations, Select Model... ... is a shortcut to create rules that will select your entire model. Rather than manually going to each entity type and adding a rule that includes all IDs (1 to 99999999), you can use this command to automatically create all of those rules in the current group. When you are asked whether to create the rules, you must press Yes or the command will end. After creating these rules, you can then go add additional rules to remove or exclude portions of your model.

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Group, Operations, Select Mesh... ...selects all the entities related to a mesh and places them into a group. After you pick the command, you select the elements for the group. FEMAP then adds the related entities which may include nodes, properties, materials, loads, and constraints.

Group, Operations, Select Region... ... enables you to put Connection Regions, Fluid Regions, Bolt Regions, and Rotor Regions into the current group AND also places the components used to define these regions into the group (i.e., if a selected Connection Region is “Defined By” the faces of 20 solid elements, those 20 elements will be added to the group as well as the Connection Region). When this command is used, the standard entity selection dialog box will appear and you can simply select the Regions to include in the group.

6.4.3.3 Group Clipping Menu The commands on this submenu are used to define the coordinate and plane clipping options for the active group. You can independently specify both coordinate clipping and up to six clipping planes. Note:

The Group Clipping Screen, Plane, and Volume commands all control the same six clipping planes. They are not independent - choosing one will override previous plane selections. FEMAP will therefore ask you to confirm that you want to turn off the previous clipping options, if they were defined using a different command. If you answer No for screen and volume clipping, the command will continue, but the defaults will be relatively meaningless. When you choose No for plane clipping, the clipping planes that were previously active will remain active. You can use this technique to edit one or more planes that you defined using screen or volume.

How Clipping is Evaluated When you specify either plane or coordinate clipping, FEMAP bases the selection of entities on coordinate locations. Points, nodes, and coordinate systems are all clipped based on their location in your model. Text that is positioned relative to your model is clipped in the same way. View positioned text can not be selected via clipping. Other entities are clipped based on the points or nodes that they reference. For example, elements are included if any of the nodes that they reference are included by clipping. It is not necessary that all of the nodes referenced by an element are included - just one. Nodal loads are included if the nodes where they are applied have been selected by clipping. Elemental loads are included only if the elements where they are applied have been selected by clipping. This implies that at least one of the nodes referenced by those elements has been included also. If you are trying to establish clipping planes to select elements, you only need to include one of the nodes to include the elements.

Group, Clipping, Coordinate... ... allows you to quickly select portions of your model based on their coordinate values relative to a selected coordinate system.

The Group Selection by Coordinate Clipping dialog box selects the clipping options. You can choose to clip Above, Below, Between, or Outside of the selected minimum and/or maximum coordinates. The Coordinate Value section allows you to select the coordinate direction that will control clipping. If you choose None, coordinate clipping will be turned off.

Group Clipping Menu

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Finally, you can select any existing coordinate system. To evaluate the clipping, FEMAP will transform the entity coordinates into the system you select and compare them against the Minimum and/or Maximum values that you specify. When you choose Above, anything which is above the Maximum will be clipped, or removed. Anything less than the Maximum will be included. Below is the opposite. Anything less than the Minimum will be clipped. Between will clip or remove anything between the Minimum and Maximum. Outside is the opposite. Clipping Non-Planar Regions If you choose a cylindrical or spherical coordinate system, the clipping region can be non-planar. For example, if you wanted to select a cylindrical volume, you could choose a cylindrical system and then clip above an X (actually a radius for a cylindrical system) value. Everything that has a radius which is smaller than the Maximum value that you specify will be included.

Group, Clipping, Screen... ... allows you to quickly orient up to four (of the possible six) clipping planes. With this command you pick a series of locations. The clipping planes will be oriented to pass through those positions and be normal to the active view hence the title Screen Clipping. Although the orientation of the active view orients the clipping planes, the planes are still defined relative to your model. That means that if you rotate the view after you define the clipping planes, the planes will not rotate. They are still defined relative to model coordinates - which cannot change. This approach insures that the same entities are always selected for the group, no matter how you orient the view.

When you invoke the command, the Group Selection by Screen Clipping dialog box will be displayed. You can choose between four possible methods to orient the clipping planes. Rectangle allows you to specify two opposite corners of a rectangular region. The sides of the rectangle are aligned with the sides of the window. The 2 Point method defines a single clipping plane which passes through the two locations and which is perpendicular to the active view. Both the 3 Point and the 4 Point methods define clipping polygons, just like the Rectangle method. With these options however, you can specify an arbitrary polygon. Although you can specify a convex polygon with the 4 Point method, it will not clip your model properly. Since all clipping is really done with planes, they can only properly be combined to form non-convex regions. The figure shows how, and why, a convex region will be improperly clipped.

This edge clips the shaded area

Clipping Polygon

This area is inside the polygon, but is still clipped by the other edge

After choosing a method, you should define the locations that you want to use to position the clipping plane or planes. While you can always type X, Y and Z coordinates, the easiest way to define these positions is to use the

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graphics cursor to choose screen locations. Simply move the cursor to the location you want and press the left mouse button. Then, move to the next location and press again. As you move the cursor around in your graphics window, you will see lines which outline the region that you are defining. These lines can assist you in properly positioning the clipping planes. If you are typing coordinates, or you just want to verify your final positions before pressing OK, you can press Preview to draw an outline around the clipping region. If you type coordinates, they must always be relative to the active coordinate system. You cannot choose an active system in this command. Before invoking this command, you can choose an active coordinate system using the Tools, Parameters command, or many others. To complete the screen clipping specification, you must choose whether to clip inside or outside the clipping region. For the methods that define polygonal regions, this choice should be obvious. For the 2 Point method, Outside chooses the side of the plane indicated by the right-hand rule going from the first to the second point and then into the screen. Choosing Outside will clip or remove all entities which lie outside of the clipping region, and will select all entities which are inside the region. Choosing Inside does just the opposite.

Group, Clipping, Plane... ... enables you to independently position the six clipping planes. For this command, the standard plane definition dialog boxes are used to position the planes. Only one plane can be positioned each time you use this command. When you choose Group, Clipping, Plane, you will see the Group Selection by Plane Clipping dialog box. You can choose which plane to define or update by selecting one of the option buttons from 1 to 6. If a plane is already active you will see the word On beside the option button. You must also choose whether to clip the positive side or negative side of the plane. The positive side is the side toward the plane normal direction. Clipping the positive side will ignore all entities on the side toward the positive plane normal and include entities on the other side. When you press OK, the standard plane definition dialog box will be displayed. You can choose any of the definition methods to orient the plane. If you want to turn a particular plane off, select the appropriate option button, and press Reset. If you want to turn all planes off, it is quicker to use the Group, Clipping, Reset command. Working with Multiple Clipping Planes By correctly choosing between the Positive Side and Negative Side options, you can clip entities on either side of a plane. When you are trying to combine multiple planes to clip a more complex region, you must be certain that these orientations are properly aligned. If they are not, you will not select the correct portion of your model. In general, if you want to select some region of your model using multiple planes, you should use the Positive Side option. Then, position the clipping planes around the periphery of the region you want to keep, with all plane normals pointing outward. As stated previously, you can not create convex clipping regions.

Group, Clipping, Volume... ... automatically positions all six clipping planes to form a cubic (hexahedral) volume. There are two methods for defining the desired volume, which you can select from the Group Selection by Volume Clipping dialog box, a 2point method or an 8-point method. The 2 Point method defines a cubic volume, aligned with the global rectangular coordinate system. For this method, when you press OK, the standard coordinate definition dialog box will be displayed twice, once for each corner. The two coordinates that you specify will define the diagonal of the clipping cube. With the 8 Point method, you can define a general hexahedron. The standard coordinate definition dialog box is displayed eight times. Each coordinate defines a corner of the hexahedron. You must specify the corners in the same order as you would for an 8-noded solid element - around the bottom face and then around the top face. Before you press OK, you must also choose whether to clip outside or inside the volume. If you clip outside, all entities which are outside of the volume you define will be skipped. The entities which are inside will be selected into the group. Clipping inside does just the opposite.

Group, Layers...

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Group, Clipping, Reset Clip... ... turns off both coordinate clipping and plane clipping. This command will ask two questions. The first asks whether you wish to turn off all plane clipping. The second asks whether to turn off coordinate clipping. If you answer Yes to either of these questions, the associated clipping options will be turned off.

6.4.3.4 Group, Layers... ... defines the layers which can be referenced by entities which are included in the group. You can not automatically select entities using this command, but you will remove them from the group if they are not on one of the active layers. The Limit Group to Selected Layers dialog box specifies the allowable layers. Initially, All layers are acceptable. If you choose one of the other options, you must specify the Minimum and/or Maximum allowable layer. The Between option will enable inclusion of entities which reference the Minimum or Maximum layers (or anything in between). Outside will allow you to select entities that reference layers numbers which are less than (but not equal to) the minimum, or that reference layers which are greater than (but not equal to) the maximum.

6.4.3.5 Grouping Individual Entities The remaining commands involve adding individual entities to the group. They are separated into different sections based upon the type of entity to group. Each entity will also have several methods available for including them in the group. Common methods to all entities include Group by ID, Color, and Layer. Additional options will be available based upon the entity (i.e. you can select curves by methods Using Point, On Surface, or On Solid, while you can select materials by methods on Property, on Element, or Type). For more information, see Section 5.9, "Groups, Layers and Viewing Your Model" in the FEMAP User Guide.

Group, Text Menu The commands on this submenu allow you to define, edit, and delete the rules which will be used to select text. You can select text into your group using the common methods only (ID, Color, or Layer).

Group, Text, ID

Group, Point Menu The commands on this submenu allow you to define, edit, and delete the rules which will be used to select points. You can select points into your group based upon ID, Color, Layer, Definition Coordinate System, Curves that reference them, or any combination of these methods.

Group, Point, ID

Group, Curve Menu The commands on this submenu allow you to define, edit, and delete the rules which will be used to select curves. You can select curves into your group based on ID, Color, Layer, Points that they reference, Surfaces that reference them, Solids that reference them, or any combination of these methods.

Group, Curve, ID

Group, Surface Menu The commands on this submenu allow you to define, edit, and delete the rules which will be used to select surfaces. You can select surfaces into your group based on their ID, Color, Layer, Curves that they reference, Volumes that reference them, Solids that reference them, or any combination of these methods.

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Group, Surface, ID

Group, Volume Menu The commands on this submenu allow you to define, edit, and delete the rules that will be used to select volumes. You can select volumes into your group based on their ID, Color, Layer, Surfaces that they reference, or any combination of these methods.

Group, Solid Menu The commands on this submenu allow you to define, edit, and delete the rules that will be used to select solids. You can select solids into your group based on their ID, Color, Layer, Curves that they reference, Surfaces they reference, or any combination of these methods.

Group, Solid, ID

Group, Connection Property Menu The commands on this submenu allow you to define, edit, and delete the rules that will be used to select Connection Properties. You can select Connection Properties into your group based on their ID, Color, Layer, On Connector (being used by a selected Connector), or any combination of these methods.

Group, Connection Property, ID

Group, Region Menu The commands on this submenu allow you to define, edit, and delete the rules that will be used to select Connection Regions, Bolt Regions, Fluid Regions, and/or Rotor Regions. There are some basic rules to select Regions into your group based on their ID, Color, Layer, or On Connector (being used by a selected Connector). There are rules for Region referencing Node (region is defined using Node(s) OR the region will include Node(s) when “expanded for export” to a solver) and referencing Element (region is defined using Element(s) and/or Faces of Element(s) OR the region will include Element(s) and/or Faces of Element(s) when “expanded for export” to a solver). Note:

When a region is “expanded for export”, the type of region defines what entity type it will be “expanded to”. In the case of Fluid Regions, surfaces may be used to define the region, which then “expand to” Element Faces. For Bolt Regions, curves may be used to define the region, which always “expand to” Elements, while Rotor Regions can only be defined using nodes, so when expanded, they are “expanded to” Nodes.

Note:

Connection Regions have the most flexibility when defining the region and also have multiple options for what entity type is requested for “output”. Therefore, a region may be defined by elements, but the output will be in nodes in which case one region could be “referenced by” both elements (defined by) and nodes (output). This is uncommon.

Additional rules for Regions include using Curve (region is defined using selected Curve(s)), using Surface (region is defined using selected Surface(s)), using Property (region is defined using selected Property(s)) or any combination of these methods.

Group, Region, ID

Group, Connector Menu The commands on this submenu allow you to define, edit, and delete the rules that will be used to select Connectors. You can select Connectors into your group based on their ID, Color, Layer, Property (Connector using a specific Connection Property), using Region (Connector using a specific Connection Region), or any combination of these methods.

Grouping Individual Entities

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Group, Connector, ID

Group, Coord Sys Menu The commands on this submenu allow you to define, edit, and delete the rules that will be used to select coordinate systems. You can select coordinate systems into your group based on their ID, Color, Layer, Definition Coordinate System, Type, defined at a Point or Node, used by a Property or other Coordinate System or any combination of these methods. The predefined global coordinate systems cannot be selected into a group.

Group, Coord Sys, ID

Group, Node Menu The commands on this submenu allow you to define, edit, and delete the rules that will be used to select nodes. You can select nodes into your group based on their ID, Color, Layer, Definition Coordinate Systems, Output Coordinate Systems, Elements that reference them, Element Orientation (selects nodes used for orientation by beam elements), Superelement ID (selects nodes with the same Superelement ID as the selected node), geometric references (Points, Curves, Surfaces, and Volume/Solids from which they were created), or any combination of these methods. The ID option has additional options under the Method area that you can use to limit the IDs to those nodes on a Free Edge, on a Free Face, Constrained or Loaded. These limitations only apply to graphical selection from the view. If you enter the ID values, or do a Select All, FEMAP will include these entities into the group.

Group, Node, ID To use the Free Edge or Free Face options, you must have performed a free edge or free face plot since your last View, Regenerate. If you have not, no free edge or face lists will be present, and no nodes will be selected. When you select ID - Constrained or ID - Constraint Equation, the Select Nodes with Constraint dialog box will appear. This dialog box enables you to limit the selected nodes to those that are constrained in any constraint set or a specific set as well specific DOFs. You must graphically select the nodes for FEMAP to properly limit the node selection. . . . When you select ID- Loaded, the Select Entities with Load dialog box will appear. You must select the type of load on the node for it to be selected in the group. In addition, you can limit it to a specific load set and magnitude range. Again, you must graphical select the nodes for FEMAP to properly limit the node selection. . . . .

Hint: If you want to select all nodes that are loaded, or constrained (or on free edges or free faces), simply do a View, Autoscale, change the method for the grouping to the appropriate ID method, and then do a box pick of the entire screen. This will select all nodes that meet the criteria.

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Other Group, Node... Icons Group, Node, Definition CSys;

Group, Node, on Curve;

Group, Node, on Element;

Group, Node, on Surface;

Group, Node, on Point;

Group, Node, in Solid/Volume

Group, Element Menu The commands on this submenu allow you to define, edit, and delete the rules that will be used to select elements. You can select elements into your group based on their ID, Color, Layer, Properties, Materials or Nodes that they reference, the Element Type, the Element Shape, geometric references (Points, Curves, Surfaces, and Volume/Solids from which they were created), or any combination of these methods. The All Nodes command will only select elements if ALL nodes of that element have been selected.

Group, Element, ID Similar to the Group Node by ID, you can limit the ID selections to those elements that have a free edge, free face, or a load applied. Other Group, Element... Icons Group, Element, Material;

Group, Element, Shape;

Group, Element, Property;

Group, Element, Layup;

Group, Element, using Node;

Group, Element, All Nodes;

Group, Element, on Curve;

Group, Element, on Surface;

Group, Element, on Point;

Group, Element, in Solid/Volume

Group, Material Menu The commands on this submenu allow you to define, edit, and delete the rules that will be used to select materials. You can select materials into your group based on their ID, Color, Layer, Properties or Elements that reference them, the Material Type, or any combination of these methods.

Group, Material, ID

Group, Property Menu The commands on this submenu allow you to define, edit, and delete the rules which will be used to select properties. You can select properties into your group based on their ID, Color, Layer, Elements that reference them, Materials that they reference, the Property Type, or any combination of these methods.

Group, Property, ID

Group, Layup Menu The commands on this submenu allow you to define, edit, and delete the rules which will be used to select layups. You can select layups into your group based on their ID, Material, on Property (selects Layup used by the selected Property) or any combination of these methods.

Group, Layup, ID

Deleting Groups (Delete, Group command)

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Group, Load Menu The commands on this submenu allow you to define, edit, and delete the rules that will be used to select loads. Since loads are defined in multiple sets, the commands on this menu really do not select the loads, but instead select the nodes, elements, and regions where the loads are applied. This allows you to choose a certain portion of your model, and include loads which are applied to that portion of your model, in all sets. When the group is used for display or selecting entities, as always, only the loads from the active load set are selected. Group, Load... Icons Group, Load, Nodal;

Group, Load, Elemental;

Group, Load, on Point;

Group, Load, on Curve;

Group, Load, on Region;

Group, Load, on Surface

Group, Constraint Menu The commands on this submenu allow you to define, edit, and delete the rules which will be used to select constraints. Since constraints are defined in multiple sets, the commands on this menu really do not select the constraints, but instead select the nodes where the constraints are applied. This allows you to choose a certain portion of your model and include constraints which are applied to that portion of your model in all sets. When the group is used for display or selecting entities, as always, only the constraints from the active constraint set are selected. Group, Load... Icons Group, Constraint, Nodal;

Group, Constraint, on Curve;

6.4.4 Deleting Groups

Group, Constraint, Equation;

Group, Constraint, on Point;

Group, Constraint, on Surface;

(Delete, Group command)

Just like any other FEMAP entity, you can delete groups. Select the Delete, Group command, then choose the group or groups to delete. You then verify that you want to delete the group(s). There are no entities that depend on groups; therefore, groups should never be nondeletable.

6.4.5 Renumbering Groups To renumber groups, pick the Modify, Renumber Groups command. Enter the groups to renumber. You will then see the Renumber To dialog box. The only orders available for groups are Original ID and Selection Order. You can also choose Ascending or Descending order, as well as Verify Renumbering. The final option, Constant Offset, allows you to renumber by simply adding a constant value to each ID.

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7.

Modeling Tools FEMAP has an extensive array of tools for checking and manipulating your model. These tools range from summing forces to performing free edge and free face plots to visualize any gaps in the model. These tools can be separated into three major areas based upon their functions and their placement in the menu: Tools, List, and View. The commands under the Tools and List menus will be explained more fully below, while View tools will be briefly discussed. For further explanation on the general operation of the viewing commands, see Section 6.1, "View Activation, Management, and Options". Tools Menu The commands on the Tools menu provide a wide variety of tools for checking and operating on your model. The Tools menu also contains commands that are not specifically designed for checking your model, but are considered general tools for your use when operating FEMAP. These commands will also be explained in this section. The FEMAP Tools menu is separated into seven categories, based upon the type of function to perform: •

command undo and redo (Section 7.1.1, "Undo and Redo")



changing the workplane (Section 7.1.2, "Tools, Workplane...")



tools for operating on your model and toolbars for easy access to commonly used commands (Section 7.2, "Dockable Panes" and Section 7.3.1, "Standard Toolbars")



settings for overall model parameters and units conversion (Section 7.4.1, "Tools, Parameters..." and Section 7.4.2, "Tools, Convert Units...")



FEMAP finite element entities used for viewing, reporting, and entering data (Section 7.4.3, "Entity Tools")



measuring and checking commands (Section 7.4.4, "Measuring Tools" and Section 7.4.5, "Checking Tools")



a “Stress Wizard” for simple single-part stress analysis (Section 7.4.6, "Tools, Stress Wizard")

Each of the above sections, with their associated commands, will be explained more fully below.

7.1 Undo and Workplane 7.1.1 Undo and Redo These commands provide a simple method of reverting backward, or moving forward through the commands you just performed. This is a very easy method to eliminate commands that have had unexpected results.

7.1.1.1 Tools, Undo...

Ctrl+Z

... removes the effect of the previous command. This allows you to “back up” one command if you made a mistake, or if you want to review the effect of the changes. The Tools, Redo command will “undo the undo”, or go forward one command. You can repeatedly use Undo to backup multiple commands. You can set the total number of commands that you can undo in the File, Preferences, Database command. When you undo a command, you will see a message in the Messages window that tells you the command that you are undoing. The graphics windows will also be updated to show the effect of undoing the command. Immediately following an Undo, you may need to use View, Redraw, prior to being able to graphically select an entity from the screen - even though the entity is displayed. If you attempt to select something, and a different entity is picked, or nothing is selected, then use View, Redraw. You cannot undo: commands on the File menu, the View, New, Activate and Window commands. They all write files, or make changes that are non-reversible. You cannot undo back through the initialization of the Parasolid advanced geometry engine since their initialization also causes non-reversible changes to the database. If you exe-

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cute any of these commands, you will be unable to back-up past that point. Other changes which you make to resize or move a window will also not be undone, but do not cause any loss of previous undo information. If you are using the autorepeat feature of the creation commands to create multiple entities, Undo will erase all of those entities as a single command. You must choose the command from the menu to be able to backup a single creation per undo.

7.1.1.2 Tools, Redo...

Ctrl+Shift+Z

... goes forward one command following an Undo. This command is only available following one or more Undo commands. It works identically to Undo, just in reverse. You can use Redo repeatedly up to the point where you are back to your last real (not Undo) command. If you have undone one or more commands, and then choose another real command, you can no longer use Redo to retrieve the undone commands.

7.1.2 Tools, Workplane...

Ctrl+W or F2

... specifies the location, size and orientation of the workplane that is used for cursor selections or defining twodimensional geometry. When you select this command, the following dialog box will appear:

These commands all involve different methods of locating the workplane. There are three major types of options: Define Plane, Move Plane, and Origin and Axes. In addition, you can change snap options or turn the drawing of the workplane on or off. Hint:

You can also access this command from any dialog box (in a text box or drop-down list) by using the Ctrl+W shortcut keys, or from the workplane option on many of the command toolbars (those related to creating geometry).

7.1.2.1 Define Plane These commands locate the workplane in space.

Select Plane/Global Plane Both the Select Plane and Global Plane options use the standard plane definition dialog box to define the model workplane. The only difference is the Global Plane method sets the default on the plane definition dialog box to that method. You can still select a different method. For more information, see Section 4.3.1, "Entity Selection" in the FEMAP User Guide.

On Surface The On Surface method allows you to align the workplane to a particular surface. When you select this method, you will see the Define Model Workplane dialog box.

Move Plane

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Enter (or graphically select) the Surface ID, the point for the origin of the workplane grid (At Point), and optionally a point along the X axis (Axis Point). FEMAP will automatically align the plane to the surface by orienting the Y axis to the surface, and then use the right-hand rule convention to align the Z axis to complete the triad. In addition, you can decide to force the surface to be in the first quadrant of the workplane (First Quadrant), reverse the direction of the normals (Reverse Direction), or provide an offset distance from the surface. The First Quadrant option may also reverse the normal direction. If you plan to perform solid boolean operations such as Extrude, it is best to leave this option off so the default directions for Add or Remove material will be properly aligned.

Previous The Previous method requires no input. It simply places the workplane at its last previous location. You can only backup one position with this command. If you perform previous twice, the workplane will be placed back at its original position.

7.1.2.2 Move Plane The Move Plane methods allow you to define the location of the workplane by translating or rotating the current workplane with a location input respect to its current location. There are three available methods for this type of procedure: Offset Distance, Move to Point, and Rotate. Offset Distance involves both translation and rotation, while Move to Point is pure translation, and Rotate is pure rotation.

Offset Distance This method allows you to both translate and rotate the workplane with respect to its normal (Z direction). When you select this method, you must enter both a Z offset (in units of length), and a rotation value (in degrees). The workplane will be translated along its normal by the translation amount, and then rotated about its normal by the rotation amount. If you want to translate or rotate in the negative direction, simply input a negative value.

Move to Point The Move to Point method simply translates the workplane origin to a specified location. The only input required is the coordinate location (via the standard coordinate definition dialog box). The workplane will maintain the same rotational orientation. It will simply be moved to that coordinate.

Rotate This method allows you to rotate the workplane around an arbitrary vector. The only inputs required are the vector to serve as the axis of rotation (defined by using the standard vector definition dialog box), and the rotation angle. As always, rotation is performed using a right-hand rule convention.

7.1.2.3 Origin and Axes These commands do not change the “plane” associated with the workplane, but simply move the origin or the axes of the workplane within that plane. The first two commands move the origin (Offset Origin and Move Origin), and the last two commands orient the X and Y axes (Align X Axis and Align Y Axis, respectively).

Offset Origin, Move Origin These two commands move the origin of the workplane. The offset origin method offsets the origin of the workplane from its current location. Only two inputs are required, X Offset and Y Offset. These offsets are in the workplane X and Y directions. Move Origin requires input of the location of the origin via the Standard Coordinate Definition Dialog box. You should typically select a location that is on the current workplane. If you do not, FEMAP will project this point onto the workplane, and the resulting origin may not be where you expected.

Align X Axis, Align Y Axis These methods allow you to align the X axis or Y axis to a vector which you define through the standard coordinate definition dialog box. You should typically select a vector that is in the current workplane. If you do not, FEMAP will project this vector onto the workplane, and the resulting axis may not be where you expected.

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7.1.2.4 Snap Options... ... defines the graphics cursor snap mode, the size and orientation of the snap grid and the grid display style. The Snap To dialog box sets these options.

The Snap To dialog box is separated into four major sections: Grid and Ruler Spacing, Grid Style, Workplane Size, and Snap To. Each of these areas are explained more fully below. Hint:

You can access this command from any dialog box (in a text box or drop-down list) by using the Ctrl+T shortcut keys, through the Quick Access command menu, or through the Workplane icon.

Grid and Ruler Spacing These options specify the spacing between snap grid locations. You can allow FEMAP to determine the spacing (Automatic), set a Uniform spacing, or a Nonuniform spacing. Automatic requires input only of the divisions. The Divisions option specifies how many minor tic marks will be drawn between every major tic. FEMAP will calculate a grid spacing based upon the model size and then use the Divisions value to further partition the grid. Uniform and Nonuniform spacing also require input of the Divisions, but you must also specify a Grid Size. For Uniform, enter a value for the X Grid Size, and FEMAP will also use this for Y. In addition, FEMAP uses this value for the ruler labels, which controls the frequency of labels on the workplane. Nonuniform requires the additional input of the Y Grid Size, and the Ruler Labels. The Ruler Labels value will be used for both grids. You cannot define nonuniform labeling.

Grid Style The Snap Grid can be displayed either as dots or lines, or it can be invisible. The style of display has no effect on whether or not the cursor snaps to a particular location. You can make the grid invisible and still snap to it. Conversely it can be displayed as dots or lines and the snap mode can be set to snap to a point, node or screen location. The display of the snap grid for an individual window can be turned on or off using the View, Options command. If the snap grid spacing is too small relative to the image displayed in a window, the dots or lines could completely fill the window. In this case, the grid will not be drawn, and you will receive a message which tells you that the grid is too dense for display.

Workplane Size This area controls the total size of the workplane grid, as well as the drawing of the X and Y rulers. The X From/To and Y From/To allow to manually scale the workplane. This can be very handy in instances when you are working on small sections of your model to define the workplane size. It is often much easier, however, to select the Adjust to Model Size and Adjust to Planar Surface options. These options will allow FEMAP to automatically scale FEMAP based upon the model size, and even attach the workplane directly to planar surfaces when the workplane coincides with a planar surface. These options are much more convenient when building a model than the manually scaling approach. The snap grid is drawn as a rectangular pattern. The size of that pattern is based on your model size and current view scale factors when using the automatic scaling. If your workplane and grid is rotated relative to your graphics

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window, the grid may not completely cover the window display area. Also, you may manually define a workplane that does not fill the screen. Even in these areas where the dots or lines are not drawn, the cursor will still snap to the grid location (assuming you have the snap mode set). The Draw X and Y Ruler controls define whether the rulers are drawn. You will also have to turn on the option to Show Rulers under View, Options, Tools and View Style, Workplane and Rulers to see the rulers.

Snap To These options choose whether the graphics cursor will select locations which correspond to a screen location (off), or will snap to the nearest snap grid location, nearest point, or nearest node. For more information on the snap to methods, see Section 4.4.3, "Snap To" in the FEMAP User Guide. Hint:

You can also set these modes from any dialog box by using the Ctrl+S (Off), Ctrl+G (Snap Grid), Ctrl+P (Point) or Ctrl+N (Node) shortcut keys, the Quick Access menu, or from the View toolbar.

Coord Only This option controls whether FEMAP will use the snap mode only during coordinate definition, or every time you select an entity from the graphics window. When this is on, FEMAP will only snap if you are trying to define a model coordinate location. All other picks will work as if snap was off. If you turn it off however, the active snap mode will always be used - even when you are picking entities, zooming, or any other time you click in the graphics window. Full Precision This option controls how FEMAP will write graphically selected coordinates into your dialog boxes. It only applies when you are snapping to nodes or points. If Full Precision is on, FEMAP will use the equation functions XND( ), YND( ), ZND( ), XPT( ), YPT( ) and ZPT( ) instead of the coordinate values. In this case, when you press OK, FEMAP will use the full double-precision database coordinates of the selected node or point. When Full Precision is off, the coordinate values are written to the dialog box. In this case, the location is only as accurate as the number of digits that are in the dialog box.

7.2 Dockable Panes FEMAP contains several “Dockable Panes” that offer different tools used to create and modify models, evaluate and sort data, create reports, and view info of specific entities. There are others which allow you to create customized features by recording macros or creating advanced programming routines by directly accessing the FEMAP database using the FEMAP API (Applications Programming Interface). Each dockable pane can be either visible or hidden by using the Tools... menu command corresponding to the specific dockable pane. For more information about general use of the dockable panes, see section Section 4.1.2.2, "FEMAP Dockable Panes" in the FEMAP User Guide. The Dockable Panes are: •

Model Info: Allows you to view and navigate around a “graphical inventory” of many “top-level” entities in your model. Also may be used to control visibility of groups, layers, and elements using element type, element shape, and associated to materials and/or properties. See Section 7.2.1, "Tools, Model Info"



Meshing Toolbox: Provides helpful tools to simplify geometry for meshing purposes (suppress and/or completely remove geometric features, create combined curves and/or boundary surfaces), modify an existing mesh and mesh sizing, and create visual plots of mesh quality. See Section 7.2.2, "Tools, Meshing Toolbox"



PostProcessing Toolbox: Provides a single location in the interface to choose any Deformed and/or Contour Style found in the View, Select command, then displays a unique set of options for each “Style”. This consolidates options needed to alter how each “Style” is displayed, which are otherwise found in several different View... commands. See Section 7.2.3, "Tools, PostProcessing Toolbox"



Entity Editor: Allows you to view, modify, choose, and create attributes, colors, connections, numerical values, settings, etc. of a single finite element, geometric, or other entity in FEMAP. See Section 7.2.4, "Tools, Entity Editor"



Data Surface Editor: Allows you to create 1-D, 2-D, and 3-D “data surfaces” used to apply varying loading conditions to your model. Data Surfaces can also be used to “map” output data from one model to create loading conditions in another model with a different mesh. See Section 7.2.5, "Tools, Data Surface Editor"

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Entity Info: When the Select Toolbar has an active entity type, this pane will display information about the each entity of that type as it is highlighted in the main graphics window. Post-processing data will also be displayed for node and element entity types when the model has a deformed style and/or contour style selected. See Section 7.2.6, "Tools, Entity Info".



Data Table: Allows you send data to an interactive, dynamically changing table using various methods to fill the table. Output data can also be added to the table and then listed and sorted. See Section 7.2.7, "Tools, Data Table".



API Programming: The API Programming dockable pane is a Visual Basic-compatible scripting editor and debugging control which allows you to create customized basic scripts inside the FEMAP interface using the FEMAP Application Programming Interface (API). The FEMAP API lets you customize FEMAP to meet your specific needs. The FEMAP API is an OLE/COM-based programming interface to FEMAP. It contains hundreds of functions that can be called from Visual Basic, VBA (Excel, Word, Access, ... ), C, or C++. See Section 7.2.8, "Tools, Programming, API Programming"



Program File: Allows you to record any number of FEMAP menu, toolbar, and keyboard commands in sequence to create macros which can then be saved and replayed later in FEMAP models. Once recording has been completed, there are other options available in the dockable pane to alter what the macro does or aid in debugging. When the Program File window is in “Record Mode”, all of the other dockable panes, except for the Messages and Entity Info panes, will be temporarily hidden and cannot be used. See Section 7.2.9, "Tools, Programming, Program File"



Messages: Provides feedback to you from FEMAP. Information such as Error and Warning information and a chronological listing of commands which have been used during the modeling process will be sent to the window. Pictures and text can also be added and manipulated inside the window to help create reports. See Section 7.2.10, "Tools, Other Windows, Messages"



Status Bar: Provides quick access to set the active Property, Load Set, Constraint Set, Group, or Output Set in your active model. Also gives the user feedback on the model and help when the cursor is positioned over a command or icon. Although it can’t be moved like the Dockable Panes, it can be toggled on and off by choosing it on the Tools, Other Windows... Menu. See Section 7.2.11, "Tools, Other Windows, Status Bar"

In many cases, the different dockable panes are designed to be used together to perform a wide variety of tasks. There are many commands allowing you to send information and data from one pane to another and help you get the most out of these powerful tools.

Tools, Model Info

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7.2.1 Tools, Model Info Collapse/Expand All Reload From Model Reset All Visibility (Defaults)

Send To Data Table Show When Selected Menu

The Model Info “tree” dockable pane allows you to view and navigate around a graphical “inventory” of many “top-level” entities in your model. The Model Info tree may also be used to control visibility of certain types of geometric entities, groups, layers, and elements using element type, element shape, and associated to materials and/or properties using check boxes. “Top-level” refers to an entity which can be used by a number of other entities. For instance, many points, curves, and surfaces make up a Solid; many entities can reference a single Coordinate System; many elements a single Property or Material; many loads can be found in a Load Set; many constraints in a Constraint Set; or many surfaces, element faces, nodes, and/or element properties can make up a Region (Connection, Fluid, Bolt, or Rotor). Aero Model entities are also available. For convenience, individual Loads and Constraints appear in the Model Info tree. In each Load set, the loads are separated into three categories, Load Definitions, Body Loads, and Other Loads. The Other Loads category is broken down further into On Geometry, On Mesh, Bolt Preload, Nodal Temperatures, and Elemental Temperatures. In each Constraint set, the constraints are separated into two categories Constraint Definitions and Other Constraints. The Other Constraints category is broken down further into On Geometry, On Mesh, and Equations. Appearing on the tree along with the “top-level” entities are data set lists used by the entire model for Analysis and viewing Results, as well as lists of existing Views, Groups, and Layers. Elements appear in the Model Info tree for visibility purposes and quick access to elements of a certain shape or type via context sensitive menus. Connections are also in the tree to facilitate turning Connectors on and off and viewing Master and Slave Connection Regions. Finally, the current Selection List being stored by the Select Toolbar can be found at the bottom of the tree. Model Info Features The “tree” is broken down into major categories and smaller sub-categories which can be expanded and collapsed to create the optimal listing for your specific modeling needs. If you hold down the Alt key while clicking a “+/-” box to expand/collapse a branch of the tree, all of the sub-branches of that branch will also be expanded/collapsed. When an entity is active, it will appear in Blue Text with Bold Type. Only one entity or set can be active in each category. You can make an entity active by double-clicking it or right-mouse clicking it in the list and choosing the Activate command on the context-sensitive menu.

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You can change the title of any entity by highlighting the entity title, then clicking it again (NOT a “double click”), which will enable editing of the entity title. In some categories, it is possible to choose multiple entities at the same time and perform operations on all of the entities at once. In order to choose multiple entities, hold down the Ctrl key and select individual entities with the mouse or hold down the Shift key and select a first entity and a last entity and all of the entities in between will also be selected (i.e., a range). Some context sensitive menu commands require that multiple entities be chosen to activate a command. The selection list shows the number of each type of entity in parenthesis after the entity type name. For instance, “Curve Loads (2)” designates there are two separate “loads on curves” in the selection list, not that the Curve Loads are on Curve 2. If the number of entities of a particular type exceed the value specified for Max Entities on the User Interface tab of the File Preferences, then Next and Previous entries will appear on the bottom and top of that branch of the tree. Double-clicking Next or Previous will move the list to the next or previous “range” of entities of that type. Rightclicking on Next or Previous in the list of entities will display a context-sensitive menu which contains options for Previous, Next, First, Start At, and Reload. Start At allows you to enter a value or choose from a list of available entities. It also allows you to search for a specific entity in the list by entering a portion of the entity title into the field provided, then pressing the Find button. If entities are found using Find, the Next and Previous buttons can then be used to cycle through the found entities in the dialog box until the desired entity is located. When an Analysis Set is being Analyzed the current Analysis Set will be shown with a Green circle, while any additional Analysis Sets waiting to still be analyzed will be shown with a Red circle. Simply highlight more than one Analysis Set and choose Analyze from the context-sensitive menu. Model Info Icons Collapse/Expand All - Collapses or expands ALL categories in the Model Info tree at once. Can be used to only show what you need to view specific entities. Reload From Model - Reloads the Model Info tree with all current information from the model. Always collapses the whole tree completely. Reset All Visibility Options - Resets all visibility options to default. Specifically in the Model Info tree, it sets the Groups option to “Show Full Model”, sets the Layers option to “View All Layers”, and sets all visibility “check boxes” to “on” for Geometry, Elements, Materials, and Properties. This command matches the functionality of the Reset All button in the View, Visibility command (See Section 6.1.4, "View, Visibility...".), which also includes displaying the active Load Set, active Constraint Set, all Entity Types, and selected Entity Labels. Send To Data Table - Sends selected data to the Data Table pane for sorting, filtering, and evaluation. Data Table MUST be “Unlocked” for this icon to be used. Show When Selected Menu - Contains a number of options to show the entities currently highlighted in the Model Info tree in the main graphics window. Entities associated with a Property, Material, Layup, Connection Property, Region, Connector, Group, Layer, individual Coordinate System, or Geometric Solids can be “shown”. By default, this command is set to off. The commands on this menu use different options of the Window, Show Entities command. Solids that have Mesh Attributes associated to a Property, but no mesh yet, will be highlighted in the graphics window when that Property is chosen from the list in the tree. For Load Definitions, Constraint Definitions, and “individual loads and constraints” in the Other Loads and Other Constraints categories, this command will “show” the entity (point, curve, surface, node, element, or bolt region) where the load or constraint is being applied. Once the options have been selected, simply clicking the Show When Selected icon will toggle this mode on/off. Setting the menu to Highlight will highlight the selected entities in the graphics window. Transparent Highlight does the same thing as Highlight, but will make all non-selected entities temporarily transparent as well. Note: The level of transparency used in the Transparent Highlight option can be adjusted using a global value for all entities using View, Options; Category: Tools and View Style; “Transparency” option. Setting the menu to Show Selected Only will actually make all entities NOT associated with the selected entities in the Model Info tree disappear temporarily until Show When Selected is toggled off or the model is regenerated.

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The Show Labels and Show Normals (shows element normals) options can be toggled on and off and the highlight color can also be chosen from the FEMAP color palette using the Highlight Color... command. Selection List When the select toolbar has been used to create a “selection set” of multiple entities, the entity type and the number of those entities in the “selection set” will appear in the Selection List located in the Model Info tree. The selection list shows the number of each type of entity in parenthesis after the entity type name. For instance, Curve Loads (2) means there are two separate “loads on curves” in the selection list, not that the Curve Loads are on Curve 2. If you highlight an entity type in the Selection List, right clicking will bring up the same Context Sensitive Menu which is available when a particular entity type is the “Active Entity” in the Select Toolbar. For more information see Section 7.3.1.6, "Tools, Toolbars, Select". Double Clicking an entity type in the Selection List will make that entity type the “Active Entity” in the Select Toolbar. You can now add more entities of that type to the Selection List by choosing them in the graphics window. Also, this makes it easy to delete one entity type at a time from the Selection List using either the Clear Active Entity command on the Select Toolbar or by simply pressing Ctrl+Delete while the entity type is highlighted in the Selection List. Visibility check boxes Visibility “check boxes” exist for toggling visibility on/off of Coordinate Systems (User-defined only), Geometry (Solids, Sheet Solids, and General Bodies), Connections (Regions and Connectors), Elements (by Element Shape, Element Type), Materials (Elements of that material), Properties (Elements of that Property), Groups (Show, Hide, and Clear options), and Layers. The check boxes for each entity type perform the same functions they do in the View, Visibility dialog box. See Section 6.1.4, "View, Visibility...". Also, multiple entities may be highlighted in a given section and special context-sensitive menus exist when the cursor is then placed over the visibility check boxes. See Model Info tree Context Sensitive Menus for more information. The space bar can be used to quickly toggle the visibility check boxes of highlighted entities in the tree. Loads and Constraints in the Model Info Tree Load Definitions In FEMAP, every time the Model, Load, “On Geometry Entity” (i.e., On Point, On Curve, On Surface), Model, Load, “FEA Entity” (i.e., Nodal, Nodal on Face, Elemental), or Model, Load, Bolt Preload is used, a “Load Definition” is also created in the Active Load Set. Each Load Definition can be given a title (if none is given, a default title will be assigned) and all of the loads created each time a Model, Load... command is used will be included in a new Load Definition. For instance, if you selected 10 nodes to apply a load with Model, Load, Nodal, the loads created on those 10 nodes would all be in the same Load Definition. All of the loads in a Load Definition can be edited at once by using the Modify, Edit, Load - Definition command. Similar commands can be used for listing and deleting of entire Load Definitions. These commands also appear on the context-sensitive menu for Load Definitions in the Model Info tree. Each Bolt Preload will also create a Load Definition. The Edit Where Applied command appears on the context sensitive menu which allows you to Edit where a Load Definition is applied (i.e., add loads or remove them from points, curves, surfaces, nodes, or elements using the standard entity selection dialog box). Note: Loads created by the Model, Load, Nonlinear Force command will NOT be placed into a load definition. This is a special load type which will appear in the appropriate category in the Other Loads. Load Definitions of the same type (i.e. Displacements on Nodes, Pressures on Elements, Forces on Surfaces, etc.), can be combined simply be highlighting multiple Load Definitions, clicking the right mouse button, and choosing Combine from the context-sensitive menu. The “combined” Load Definition will use the lowest ID of the combined Load Definitions and maintain that definition’s title as well. Note: Load Definitions of the different types cannot be combined, so if you try to combine “Forces on Nodes” with “Pressures on Elements” nothing will happen. On the other hand, if you highlight 5 Load Definitions (3 of load type “A” and 2 of load type “B”), the result will be 2 total Load Definitions (One a combination of the 3 load type “A” definitions and the other a combination of the 2 load type “B” definitions). This can be helpful for consolidating your Load Definitions, but if a “combined” Load Definition is edited, ALL of the individual loads in that definition will reflect the edited values.

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You can highlight any number of Load Definitions, then click the right mouse button and choose Remove Definition from the context-sensitive menu. All of the highlighted Load Definitions will disappear from the Model Info tree and the individual loads from each of them will be placed in the appropriate Other Loads category. Body Loads Body Loads are loads which act on the entire model, not individual nodes or elements. In FEMAP the body loads are Translational Acceleration (Gravity), Rotational Acceleration, Rotational Velocity, and Default Temperature. These loads are created using the Model, Load, Body command. For more information on Body Loads, please see Section 4.3.3.1, "Model, Load, Body". Body loads can be edited, listed, or deleted using the Body Loads context-sensitive menu in the Model Info Tree. Other Loads All new loading conditions created on geometry, FEA entities, or Bolt Preloads in FEMAP will be placed into Load Definitions. This is not the case when an analysis model (such as a NX Nastran input file) or a Pre-version 9.3 FEMAP Neutral File is imported into FEMAP, because no Load Definitions exist in these files. Therefore, all of these loads end up in Other Loads. In general, any loads that are NOT in a Load Definition will automatically be placed in the Other Loads section under the appropriate category. For instance, all loads on nodes or elements (except temperatures) will appear in the On Mesh category, while any geometry-based loading can be found in the On Geometry category. You can highlight any number of loads of the same type (i.e. Displacements on Nodes, Pressures on Elements, Forces on Surfaces, etc.), then click the right mouse button and choose Create Definition from the context-sensitive menu. If there are currently no load definitions, FEMAP will create a new one. If Load Definitions already exist, FEMAP will ask if you want to add the highlighted loads to an “existing Load Definition” or create a new one. Note: Only loads of the same type (i.e. Displacements on Nodes, Pressures on Elements, Forces on Surfaces, etc.) can be placed into an existing Load Definition. The values of the actual loads do not need to be the same, although if the new Load Definition is edited, all the loads will reflect the new values. Note: If you have chosen loads of multiple types AND a Load Definition currently exists for every different highlighted load type, you will have the option to add the loads from each type to an existing Load Definition one type at a time. If you have chosen loads of multiple types, BUT a Load Definition currently does not exist for every highlighted type, FEMAP will simply create a new Load Definition for each load type. Load Definitions of the same type can always be combined in the Load Definitions section. Constraint Definitions In FEMAP, every time the Model, Constraint, “On Geometry Entity” (i.e., On Point, On Curve, On Surface) or Model, Load, “FEA Entity” (i.e., Nodal, Nodal on Face, Equation) a “Constraint Definition” is also created in the Active Constraint Set. Constraint Definitions are very similar to Load Definitions and can be applied, edited, edited where applied, listed, deleted, and combined in a similar manner. Constraint Definitions can also be “removed” and the individual constraints from each Constraint Definition will be placed in the appropriate Other Constraints category. Other Constraints All new boundary conditions created on geometry or FEA entities in FEMAP will be placed into Constraint Definitions. This is not the case when an analysis model (such as a NX Nastran input file) or a Pre-version 9.3 FEMAP Neutral File is imported into FEMAP, because no Constraint Definitions exist in these files. Therefore, all of these boundary conditions end up in Other Constraints. In general, any constraints that are NOT in a Constraint Definition will automatically be placed in the Other Constraints section under the appropriate category. For instance, all constraints on nodes will appear in the On Mesh category, while any geometry-based constraints can be found in the On Geometry category. Constraint Equations have their own category in Other Constraints.

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Model Info tree Context Sensitive Menus When an individual entity or category name in the tree is selected, you can right mouse click on the selected entity or category name and a context sensitive menu will appear corresponding to that particular entity type. These context sensitive menus provide a quicker path to many frequently used commands for the specific entity type. Additional context-sensitive menus exist for visibility when the right mouse is clicked over any of the visibility “check boxes” under Coordinate Systems, Geometry, Connections - Regions, Connections - Connectors, Elements (Element Shape or Element Type), Materials, Properties, Groups, or Layers. When a category name is selected, the command chosen on the context sensitive menu will be applied to all of the entities in that category. For example, highlighting Properties and then choosing List will list all of the properties in the model. For entity types in the Selection List, right mouse clicking will display the same context sensitive menus which are available for each specific entity type when active in the Select Toolbar (For the list of Context Sensitive Menus from the Select Toolbar, see Section 7.3.1.6, "Tools, Toolbars, Select"). Here is a list of what appears on each entity type’s context sensitive menu in the Model Info tree: Coordinate Systems Command New Activate Copy Edit List Delete Move Rotate

Description Prompts you to create a new coordinate system Makes the selected coordinate system the active coordinate system in the model. Allows you to copy the selected coordinate system(s) Allows you to edit the selected coordinate system(s) one at a time. Lists information about the selected coordinate system(s) to the Messages pane Deletes the selected coordinate system(s) from the model. The three basic coordinate systems, Basic Rectangular, Basic Cylindrical, and Basic Spherical cannot be deleted. Allows you to move a coordinate system(s) from one place to another using the Modify, Move By, Coord Sys... command Allows you to rotate a coordinate system(s) from one place to another using the Modify, Rotate By, Coord Sys... command

Coordinate Systems (Visibility menu) Command Show Selected Only Show Selected Hide Selected Show All Hide All

Description Sets visibility for all Coordinate Systems highlighted in the tree to “on”, while setting all others to “off” Sets visibility for all Coordinate Systems highlighted in the tree to “on” Sets visibility for all Coordinate Systems highlighted in the tree to “off” Sets visibility to “on” for all Coordinate Systems listed in the tree. Sets visibility to “off” for all Coordinate Systems listed in the tree.

Geometry (Solids Only) Command New Activate List Delete Group Automatic Connection Mesh Size

Description Prompts you to create a new solid Makes the selected solid the active solid in the model Lists information about the selected solid(s) to the Messages pane Deletes the selected solid(s) from the model Invokes the Group, Operations, Generate Solid command. For more information, see Section 6.4.3.2, "Group, Operations Menu". Allows you to automatically create connections between multiple solids using the Connect, Automatic... command. You must have multiple solids selected for this command to be available. Allows you to set the mesh size on the selected solid(s) using the Mesh, Mesh Control, Size On Solid... command

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Modeling Tools

Command Attributes Tet Mesh Hex mesh

Description Allows you to set up meshing attributes on a selected solid using the Mesh, Mesh Control, Attributes On Solid... command Meshes the selected solid(s) with tetrahedral elements (Tets) using the Mesh, Geometry, Solids... command Meshes the selected solid(s) with hexahedral elements (Bricks) using the Mesh, Geometry, HexMesh Solids... command

Geometry (Visibility menu) Command Show Selected Only Show Selected Hide Selected Show All Hide All

Description Sets visibility for all Geometric entities highlighted in the tree to “on”, while setting all others to “off” Sets visibility for all Geometric entities highlighted in the tree to “on” Sets visibility for all Geometric entities highlighted in the tree to “off” Sets visibility to “on” for all Geometric entities listed in the tree. Sets visibility to “off” for all Geometric entities listed in the tree.

Connections (Top Level) Command Automatic Surfaces Delete All

Description Invokes the Connect, Automatic... command. For more information, seeSection 4.4.1, "Connect, Automatic..." Invokes the Connect, Surfaces... command. For more information, see Section 4.4.2, "Connect, Surfaces..." Deletes all Connection Properties, Connection Regions, and Connectors in the model.

Connections - Properties Command New Activate Copy Edit List Delete

Description Prompts you to create a new Connection Property Makes the selected Connection Property the active Connection Property in the model Allows you to copy the selected Connection Property(s). Allows you to edit the selected Connection Property(s) one at a time. Lists information about the selected Connection Property(s) to the Messages pane Deletes the selected Connection Property(s) from the model

Connections - Regions Command New Connection Region New Fluid Region New Bolt Region New Rotor Region Show Expanded

Reverse Enable Region

Description Prompts you to create a new Connection Region Prompts you to create a new Fluid Region Prompts you to create a new Bolt Region Prompts you to create a new Rotor Region for Rotor Dynamics. Highlights the individual elements or nodes and those associated to a geometric entity or property which will be exported to the solver. Helpful when a Region has been “Defined By” using the Curve, Surface, or Part/Property options. Reverses the faces of elements or the side of surfaces used for the region. Designates the Region (Fluid, Bolt, and Rotor only) is Enabled, meaning the Region will be written out when the analysis model is exported. By default, all Regions are Enabled.

Tools, Model Info

Command Disable Region

Copy Edit List Delete

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Description Designates the Region (Fluid, Bolt, and Rotor only) is Disabled, meaning the Region will NOT be written out when the analysis model is exported. Having the ability to “enable “and “disable” regions can be very useful when trying different numbers of MFLUIDs, Bolt Preloads, and Rotors. Allows you to copy the selected Region(s). Allows you to edit the selected Region(s) one at a time. Lists information about the selected Region(s) to the Messages pane Deletes the selected Region(s) from the model

Connections - Regions (Visibility menu) Command Show Selected Only Show Selected Hide Selected Show All Hide All

Description Sets visibility for all Regions highlighted in the tree to “on”, while setting all others to “off” Sets visibility for all Regions highlighted in the tree to “on” Sets visibility for all Regions highlighted in the tree to “off” Sets visibility to “on” for all Regions listed in the tree. Sets visibility to “off” for all Regions listed in the tree.

Connections - Connectors Command New Show Master (Target) Show Slave (Source) Reverse Enable Connector Disable Connector Edit List Delete Edit Property Select Property

Description Prompts you to create a new Connector Highlights the Connection Region designated as the Master in the selected Connector in the graphics window. Highlights the Connection Region designated as the Slave in the selected Connector in the graphics window. Reverses the Slave and Master Connection Regions in the selected Connector. In other words, it makes the region designated the Master the Slave and the Slave the Master. Designates the Connector is Enabled, meaning the connection will be written out when the analysis model is exported. By default, all Connectors are Enabled. Designates the Connector is Disabled, meaning the Connector will NOT be written out when the analysis model is exported. Allows you to edit the selected Connector(s) one at a time. Lists information about the selected Connector(s) to the Messages pane Deletes the selected Connector(s) from the model Allows you to edit the Connection Property(s) designated in the selected Connector(s). Allows you to select a Connection Property from a list of existing Connection Properties to be used in the selected Connector(s).

Connections - Connectors (Visibility menu) Command Show Selected Only Show Selected Hide Selected Show All Hide All

Description Sets visibility for all Connectors highlighted in the tree to “on”, while setting all others to “off” Sets visibility for all Connectors highlighted in the tree to “on” Sets visibility for all Connectors highlighted in the tree to “off” Sets visibility to “on” for all Connectors listed in the tree. Sets visibility to “off” for all Connectors listed in the tree.

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Modeling Tools

Aero Model - Panels/Bodies Command New Copy Edit List Delete Color Layer

Description Prompts you to create a new Panel/Body Allows you to copy the selected Panel/Body(s). Allows you to edit the selected Panel/Body(s) one at a time. Lists information about the selected Panel/Body(s) to the Messages pane Deletes the selected Panel/Body(s) from the model Allows you to change the color of the selected Panel/Body(s) Allows you to change the layer of the selected Panel/Body(s)

Aero Model - Panels/Bodies (Visibility menu) Command Show Selected Only Show Selected Hide Selected Show All Hide All

Description Sets visibility for all Panels/Bodies highlighted in the tree to “on”, while setting all others to “off” Sets visibility for all Panels/Bodies highlighted in the tree to “on” Sets visibility for all Panels/Bodies highlighted in the tree to “off” Sets visibility to “on” for all Panels/Bodies listed in the tree. Sets visibility to “off” for all Panels/Bodies listed in the tree.

Aero Model - Properties Command New Activate Copy Edit List Delete Color Layer

Description Prompts you to create a new Aero Property Makes the selected Aero Property the active material in the model. Allows you to copy the selected Aero Property(s). Allows you to edit the selected Aero Property(s) one at a time. Lists information about the selected Aero Property(s) to the Messages pane Deletes the selected Aero Property(s) from the model Allows you to change the color of the selected Aero Property(s) Allows you to change the layer of the selected Aero Property(s)

Aero Model - Splines Command New Copy Edit List Delete Color Layer

Description Prompts you to create a new Aero Spline Allows you to copy the selected Aero Spline(s). Allows you to edit the selected Aero Spline(s) one at a time. Lists information about the selected Aero Spline(s) to the Messages pane Deletes the selected Aero Spline(s) from the model Allows you to change the color of the selected Aero Spline(s) Allows you to change the layer of the selected Aero Spline(s)

Aero Model - Splines (Visibility menu) Command Show Selected Only Show Selected Hide Selected Show All Hide All

Description Sets visibility for all Aero Splines highlighted in the tree to “on”, while setting all others to “off” Sets visibility for all Aero Splines highlighted in the tree to “on” Sets visibility for all Aero Splines highlighted in the tree to “off” Sets visibility to “on” for all Aero Splines listed in the tree. Sets visibility to “off” for all Aero Splines listed in the tree.

Tools, Model Info

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Aero Model - Control Surfaces Command New Copy Edit List Delete Color Layer

Description Prompts you to create a new Control Surface Allows you to copy the selected Control Surface(s). Allows you to edit the selected Control Surface(s) one at a time. Lists information about the selected Control Surface(s) to the Messages pane Deletes the selected Control Surface(s) from the model Allows you to change the color of the selected Control Surface(s) Allows you to change the layer of the selected Control Surface(s)

Aero Model - Control Surfaces (Visibility menu) Command Show Selected Only Show Selected Hide Selected Show All Hide All

Description Sets visibility for all Control Surface highlighted in the tree to “on”, while setting all others to “off” Sets visibility for all Control Surface highlighted in the tree to “on” Sets visibility for all Control Surface highlighted in the tree to “off” Sets visibility to “on” for all Control Surface listed in the tree. Sets visibility to “off” for all Control Surface listed in the tree.

Model - Elements (available under By Type or By Shape headings) Command Edit List Delete Load Color Layer Copy Rotate Reflect Move By Rotate By Align

Description Allows you to edit the selected elements Lists information about the selected elements to the Messages pane Deletes the selected elements from the model Brings up the Create Loads on Elements dialog box to enable you to create loads on elements. Allows you to change the color of selected elements by bringing up the Color Palette dialog box Allows you to place the selected elements onto a different layer by bringing up the Select Layer dialog box Copies the selected elements using the Mesh, Copy, Elements... command Rotates the selected elements about an axis using the Mesh, Rotate, Element... command Reflects the selected elements referencing a plane using the Mesh, Reflect, Element... command Moves selected elements to a new location using the Modify, Move By, Element... command. Rotates selected elements about an axis using a rotation angle and/or a translation distance. Uses the Modify, Rotate By, Element... command Aligns selected elements using the Modify, Align, Element... command. See Section 4.8.1.5, "Modify, Align Menu" for more information.

Model - Elements (Visibility menu for By Shape and By Type headings) Command Show Selected Only Show Selected Hide Selected Show All Hide All

Description Sets visibility for all highlighted element types/element shapes in the tree to “on”, while setting all others to “off” Sets visibility for all highlighted element types/element shapes in the tree to “on” Sets visibility for all highlighted element types/element shapes in the tree to “off” Sets visibility to “on” for all element types/element shapes Sets visibility to “off” for all element types/element shapes

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Modeling Tools

Model - Materials Command New Activate Copy Edit List Delete Color Layer Group

Description Prompts you to create a new material Makes the selected property the active material in the model. Allows you to copy the selected material(s). Allows you to edit the selected material(s) one at a time. Lists information about the selected material(s) to the Messages pane Deletes the selected material(s) from the model Allows you to change the color of the selected material(s). If multiple materials are selected, you will have the option to randomly set a color for each unique material. Allows you to change the layer of the selected material(s). Runs the Group, Operations, Generate Material command. For more information, see Section 6.4.3.2, "Group, Operations Menu".

Model - Materials (Visibility menu) Command Show Selected Only Show Selected Hide Selected Show All Hide All Show Elements with no Material

Description Sets visibility for all elements associated to highlighted Materials in the tree to “on”, while setting all others to “off” Sets visibility for all elements associated to highlighted Materials in the tree to “on” Sets visibility for all elements associated to highlighted Materials in the tree to “off” Sets visibility to “on” for all elements associated to all Materials in the model. Sets visibility to “off” for all elements associated to all Materials in the model. Toggles visibility for all elements associated with NO Material on/off

Model - Properties Command New Activate Copy Edit List Delete Color Layer Group

Description Prompts you to create a new property Makes the selected property the active property in the model Allows you to copy the selected property or properties. Allows you to edit the selected property or properties one at a time. Lists information about the selected property or properties to the Messages pane Deletes the selected property or properties from the model Allows you to change the color of the selected properties. If multiple properties are selected, you will have the option to randomly set a color for each unique property. Allows you to change the layer of the selected properties. Runs the Group, Operations, Generate Property command. For more information, see Section 6.4.3.2, "Group, Operations Menu".

Model - Properties (Visibility menu) Command

Description

Show Selected Only Show Selected Hide Selected Show All Hide All Show Elements with no Property

Sets visibility for all elements associated to highlighted Properties in the tree to “on”, while setting all others to “off” Sets visibility for all elements associated to highlighted Properties in the tree to “on” Sets visibility for all elements associated to highlighted Properties in the tree to “off” Sets visibility to “on” for all elements associated to all Properties in the model. Sets visibility to “off” for all elements associated to all Properties in the model. Toggles visibility for all elements associated with NO Property on/off

Tools, Model Info

7-17

Model - Layups Command New Global Ply

Copy Edit List Delete Show

Description Prompts you to create a new layup Displays the Global Ply Definition dialog box, which allows creation and/or manipulation of a Global Ply for use in multiple Layups. See Section 4.2.5, "Model, Layup..." for more information. Allows you to copy the selected layup(s). Allows you to edit the selected layup(s) one at a time. Lists information about the selected layup(s) to the Messages pane Deletes the selected layup(s) from the model Brings up the Layup Viewer window. This visualization tool allows you to view a graphical representation of the selected Layup with various plotting options for ply orientation, thickness, and material. For more information, see Section 4.2.5.1, "Layup Viewer"

Model - Loads and Individual Load Sets Command

Description

New

Prompts you to create a new load set using the New Load Set dialog box of the Load Set Manager. Activate Makes the selected load set the active load set in the model. Copy Creates a copy for each of the selected load set(s) List Lists information about the selected load set(s) to the Messages pane Delete Deletes the selected load set(s) from the model Show Loaded Highlights in the graphics window, the nodes, elements, regions, and geometric entities Entities that are loaded in the model. Uses the Window, Show Entities... command to highlight the entities. Multiple load sets can be chosen for this command. Referenced Only available when a “Nastran LOAD Combination” set type is highlighted. Displays Sets the Referenced Load Sets for Nastran LOAD dialog box, which allows you to choose any number of “Standard” Load Sets used to create a LOAD entry for Nastran. See Section 4.3.1.1, "Model, Load, Create/Manage Set..." for more information. Body Brings up the dialog box from the Model, Load, Body... command to create body loads Nonlinear Brings up the dialog box from the Model, Load, Nonlinear Analysis... command to set Analysis options for nonlinear analysis. Dynamic Brings up the dialog box from the Model, Load, Dynamic Analysis... command to set Analysis options for dynamic analysis. Heat Transfer Brings up the dialog box from the Model, Load, Heat Transfer... command to set options for Heat Transfer analysis. Model - Loads - Load Definitions Command

Description

Nodal Nodal on Face Elemental On Point On Curve On Surface Bolt Preload Edit Where Applied Edit Load List

Prompts you to create a new Load Definition using the Model, Load, Nodal command. Prompts you to create a new Load Definition using the Model, Load, Nodal on Face command Prompts you to create a new Load Definition using the Model, Load, Elemental command Prompts you to create a new Load Definition using the Model, Load, On Point command Prompts you to create a new Load Definition using the Model, Load, On Curve command Prompts you to create a new Load Definition using the Model, Load, On Surface command Prompts you to create a new Load Definition using the Model, Load, Bolt Preload command Allows you to edit where the selected load definition(s) is applied (i.e., on what entities) one at a time Allows you to edit the value of the selected load definition(s) one at a time Lists information about the selected load definition(s) to the Messages pane

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Modeling Tools

Command Delete Combine

Remove Definition

Description Deletes the selected load definition(s) from the model (all individual loads in the selected definition(s) will be completely deleted from the model) Combines selected load definitions of the same load type together and uses the lowest ID of the selected load definitions as the ID for the “combined” load definition. Only available when multiple load definitions are highlighted (hold CTRL key while clicking individual load definitions or SHIFT key to select a first load definition and a last load definition and all load definitions in between). Allows you to “remove” the individual loads from the highlighted load definitions. The load definition(s) will disappear from the model completely and the individual loads from each of them will then be placed in the appropriate Other Loads category

Model - Loads - Body Loads Command Edit List Delete

Description Prompts you to edit the Body Loads for that particular load set. Lists the Body Loads for that particular load set to the Messages pane. Deletes the Body Loads for that particular load set.

Model - Loads - Other Loads (available for all of the different categories) Command

Description

Edit List Delete Create Definition

Prompts you to edit the individual load(s) one at a time. Lists the selected individual load(s) to the Messages pane. Deletes the selected individual load(s) from the model. Allows you to highlight any number of loads of the same type (i.e. Displacements on Nodes, Pressures on Elements, Forces on Surfaces, etc.) and create a Load Definition. If there are currently no load definitions, FEMAP will create a new one. If Load Definitions already exist, FEMAP will ask if you want to add the highlighted loads to an “existing Load Definition” or create a new one Allows you to highlight any number of loads and will automatically create new load definitions based on load type, load values, and additional load information (i.e., loaded face of an element). A new definition will be created for loads of the same type which have different values and/or different additional load information, which differs from the Create Definition command.

Auto Create Definition

Model - Constraints and Individual Constraint Sets Command New

Description

Prompts you to create a new load set using the New Constraint Set dialog box of the Constraint Set Manager. Activate Makes the selected constraint set the active constraint set in the model. Copy Creates a copy for each of the selected constraint set(s) List Lists information about the selected constraint set(s) to the Messages pane Delete Deletes the selected constraint set(s) from the model Show Constrained Highlights in the graphics window, the nodes and geometric entities that are conEntities strained in the model. Uses the Window, Show Entities... command to highlight the entities. Multiple constraint sets can be chosen for this command. Referenced Sets Only available when a “Nastran SPCADD/MPCADD Combination” set type is highlighted. Displays the Referenced Constraint Sets for Nastran SPCADD/MPCADD dialog box, which allows you to choose any number of “Standard” Constraint Sets used to create a SPCADD/MPCADD entry for Nastran. See Section 4.3.7.1, "Model, Constraint, Create/Manage Set..."for more information.

Tools, Model Info

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Model - Constraints - Constraint Definitions Command Nodal Nodal on Face Equation On Point On Curve On Surface Edit Where Applied Edit Constraint List Delete Combine

Remove Definition

Description Prompts you to create a new Constraint Definition using the Model, Constraint, Nodal command. Prompts you to create a new Constraint Definition using the Model, Constraint, Nodal on Face command Prompts you to create a new Constraint Definition using the Model, Constraint, Equation command Prompts you to create a new Constraint Definition using the Model, Constraint, On Point command Prompts you to create a new Constraint Definition using the Model, Constraint, On Curve command Prompts you to create a new Constraint Definition using the Model, Constraint, On Surface command Allows you to edit where the selected constraint definition(s) is applied (i.e., on what entities) one at a time Allows you to edit the value of the selected constraint definition(s) one at a time Lists information about the selected constraint definition(s) to the Messages pane Deletes the selected constraint definition(s) from the model (all individual constraints in the selected definition(s) will be completely deleted from the model) Combines selected constraint definitions of the same load type together and uses the lowest ID of the selected constraint definitions as the ID for the “combined” constraint definition. Only available when multiple constraint definitions are highlighted (hold CTRL key while clicking individual constraint definitions or SHIFT key to select a first constraint definition and a last constraint definition and all constraint definitions in between). Allows you to “remove” the individual constraints from the highlighted constraint definitions. The constraint definition(s) will disappear from the model completely and the individual constraints from each of them will then be placed in the appropriate Other Constraints category

Model - Constraints - Other Constraints (available for all of the different categories) Command

Description

Edit List Delete Create Definition

Prompts you to edit the individual constraint(s) one at a time. Lists the selected individual constraint(s) to the Messages pane. Deletes the selected individual constraint(s) from the model. Allows you to highlight any number of constrain of the same type and create a Constrain Definition. If there are currently no constraint definitions, FEMAP will create a new one. If Constraint Definitions already exist, FEMAP will ask if you want to add the highlighted constraints to an “existing Constraint Definition” or create a new one

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Modeling Tools

Model - Functions Command New Copy Edit List Delete Show

Copy to Clipboard

Paste to Clipboard

Description Prompts you to create a new function Allows you to copy the selected function(s). Allows you to edit the selected function(s) one at a time. Lists information about the selected function(s) to the Messages pane Deletes the selected function(s) from the model Brings up a new window called “XY Show” and plots the selected function in an XY plot. If multiple functions are selected and then shown, they will all appear on the same plot in the XY Show window. Up to 9 functions can be shown at once. The XY Show window is a created view and will remain with the model until it is deleted. Copies a selected function to the clipboard. Once copied onto the clipboard, you can then click another function and use the Paste command on the context sensitive menu and be prompted to replace the function or add the functions together. Once copied, you can also use the New command on the context sensitive menu and then click the Get button to paste the values into the new function. Because the function is copied onto the clipboard, it can also be pasted into a spreadsheet program, such as Excel. Pastes function data from the clipboard into a selected function. When using the Paste command after copying a function, a Yes or No dialog box will appear asking “OK to Clear Existing Function Entries (No=Combine)?”. Clicking Yes will replace all the function data, while clicking No will combine the values of the two functions together. You can also use the Paste command to paste in tabular data that was copied to the clipboard from a spreadsheet, such as Excel.

Model - Data Surfaces Command Reload/Edit List Delete

Description Loads the highlighted Data Surface into the Data Surface Editor to view or edit. Lists information about the selected Data Surface(s) to the Messages pane Deletes the selected Data Surface(s) from the model

Analyses Command Manage

Description

Displays the FEMAP Analysis Set Manager (Model, Analysis...). Once in the Analysis Set Manager, you can create new analysis sets, edit existing sets, preview input files for Nastran, export input files to different solvers, and/or invoke analysis programs for solving. Activate Makes the selected analysis set the active analysis set in the model. List Lists information about the selected analysis set(s) to the Messages pane Delete Deletes the selected analysis set(s) from the model Preview Brings up the Preview Analysis Input File dialog box which you can use to look at the input file FEMAP will create before exporting the input file. By clicking the “Edit Preview” check box, you can make changes to the input file and then click the Export or Analyze button. Preview only works for Nastran input decks at this time. Export Brings up dialog box to export an input deck for the selected analysis program. Analyze Exports an input file and starts the selected analysis program (NX Nastran, MSC Nastran, ANSYS, ABAQUS, NEi/Nastran, etc.) or the displays the “VisQ” program to launch an analysis program. Multi-selection allows multiple Analysis Sets to be analyzed one after another in series. Clear Analysis Clears the internal system analysis queue of analysis jobs waiting to be solved. Queue

Tools, Model Info

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Results Command

Description

Activate List Compare

Makes the selected results set the active results set in the model. Lists information about the selected results set(s) to the Messages pane Compares selected results sets using the List, Output, Compare command (see Section 8.6.2, "List, Output, Compare..." for more details). The first results set highlighted in the tree, chronologically, is compared to all other selected results sets. Does NOT include “List Details” information from List, Output, Compare command. Delete Deletes the selected results set(s) from the model Send Output Sends ALL the output vectors from the selected results set to the Data Table dockable Vectors to Data pane to be sorted, filtered, and evaluated. Data Table MUST be unlocked for this comTable mand to be available. No Deformation Shows no deformation for the selected results set(s) in the current view. Equivalent to using the View, Select... command and choosing “None - Model Only” in the Deformed Style section. Brings up dialog box to export an input deck for the selected analysis program. Deform Shows a deformed plot for the selected results set in the current view. Equivalent to using the View, Select... command and choosing “Deform” in the Deformed Style section Animate Shows a animated plot of deformation for the selected results set in the current view. Equivalent to using the View, Select... command and choosing “Animate” in the Deformed Style section. MultiSet Animate Shows an animated plot of deformation created from the deformation data of multiple results sets in the current view. Only available when multiple results sets are highlighted (hold CTRL key while clicking individual results sets or SHIFT key to select a first set and a last set and all sets in between). Equivalent to using the View, Select... command and choosing “Animate-MultiSet” in the Deformed Style section. Vector Shows a vector plot of deformation for the selected results set in the current view. Equivalent to using the View, Select... command and choosing “Vector” in the Deformed Style section No Contour Shows no contour plot for the selected results set(s) in the current view. Equivalent to using the View, Select... command and choosing “None - Model Only” in the Contour Style section. Contour Shows a contour plot for the selected results set in the current view. Equivalent to using the View, Select... command and choosing “Contour” in the Contour Style section. Criteria Shows a criteria plot for the selected results set in the current view. Equivalent to using the View, Select... command and choosing “Criteria” in the Contour Style section. Post Data Brings up the Select PostProcessing Data dialog box. Equivalent to using the View, Select... command and clicking the “Deformed and Contour Data” button or performing a right mouse click on the graphics window and choosing Post Data Views Command

Description

Update Active Window Open New Window New List Delete

Makes the selected window the active window and brings it to the top for viewing and other operations. If an existing view is currently not visible, this command will open a new window for this view. Brings up a copy of the current view in a new window Lists information about the selected view(s) to the Messages pane Deletes the selected view(s) from the model

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Modeling Tools

Groups Command

Description

New Copy Combine

Creates a new group via the New Group dialog box of the Group Manager. Allows you to copy the selected group(s) with all rules, clipping options, and entities. Combines selected groups together and creates a new group. Only available when multiple groups are highlighted (hold CTRL key while clicking individual groups or SHIFT key to select a first group and a last group and all groups in between) Add Related Adds ALL other entities that are somehow related to the entities currently in a selected Entities Group to that Group. See Group, Operations, Add Related Entities entry in Section 6.4.3.2, "Group, Operations Menu" Automatic Add Toggles on/off Group, Operations, Automatic Add for the selected group Show Full Model Changes the View, Visibility option on the Group tab to “Show Full Model” Show Active Changes the View, Visibility option on the Group tab to “Show Active Model” Group Show Multiple Changes the View, Visibility option on the Group tab to “Show/Hide Multiple Groups” Groups Activate Makes the selected group the active group in the model. List Lists information about the selected group(s) to the Messages pane Delete Deletes the selected group(s) from the model Referenced Displays the Referenced Groups dialog box which allows an existing group to “referGroups ence” other existing groups in a model (essentially, create a “Group of Groups”). See Section 6.4.3.1, "Group, Create/Manage..." for more information on using this functionality. Add to Selection Allows you to add entities in a selected group or number of groups to the Selection List. Export Neutral Exports a FEMAP neutral file of the selected group. In order for you to get a neutral file that will read into a new FEMAP database, you must remember to include all the nodes on any selected elements, all points on selected curves, curves on selected surfaces, surfaces making up selected solids, and materials and properties used by elements. Without all of these entities, FEMAP may give you error messages and may not be able to read in the neutral file correctly. A good way to make sure this is all taken care of is to run the Group, Operations, Add Related command before Groups (Visibility menu) Command

Description

Show Selected Groups Only Show Selected Groups Hide Selected Groups Clear Selected Groups Show Selected, Hide Referenced Groups Show All Groups Clear All Groups Show Full Model Show Active Group Show Multiple Groups

Sets visibility for all groups highlighted in the tree to “Show”, while setting all others to “Clear” Sets visibility for all groups highlighted in the tree to “Show” Sets visibility for all groups highlighted in the tree to “Hide” Sets visibility for all groups highlighted in the tree to “Clear” Sets visibility for all “groups which reference other groups” highlighted in the tree to “Show”, while setting all of the “referenced groups” in the “groups which reference other groups” to “Hide”. Sets visibility for all groups to “Show” Sets visibility for all groups to “Clear” Changes the View, Visibility option on the Group tab to “Show Full Model” Changes the View, Visibility option on the Group tab to “Show Active Model” Changes the View, Visibility option on the Group tab to “Show/Hide Multiple Groups”

Tools, Model Info

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Layers Command New Activate View All Layers View Visible Layers Only List Delete

Description Creates a new layer using the New Layer dialog box of the Layer Manager. Makes the selected layer the active layer in the model. Set the View, Visibility option on the Layer tab to “View All Layers” Set the View, Visibility option on the Layer tab to “View Multiple Layers” Lists information about the selected layer(s) to the Messages pane Deletes the selected layer(s) from the model

Layers (Visibility menu) Command Show Selected Only Show Selected Hide Selected Show All Hide All View All Layers View Visible Layers Only

Description Sets visibility for all highlighted Layers in the tree to “on”, while setting all others to “off” Sets visibility for all highlighted Layers in the tree to “on” Sets visibility for all highlighted Layers in the tree to “off” Sets visibility to “on” for all Layers in the model. Sets visibility to “off” for all Layers in the model. Set the View, Visibility option on the Layer tab to “View All Layers” Set the View, Visibility option on the Layer tab to “View Multiple Layers”

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Modeling Tools

7.2.2 Tools, Meshing Toolbox The Meshing Toolbox contains individual tools which can be very helpful during the meshing process. There are tools which allow you to simplify geometry; create “combined” geometric entities for meshing purposes using several “underlying” geometric entities; change the mesh size, biasing, and other options on any number of curves interactively; move any number of nodes dynamically while seeing the mesh update; and plot the element quality in the graphics window. The Meshing Toolbox also contains the Entity Locator, which can be used to locate Curves or Surfaces in your model which meet certain search criteria (for example, “short” curves or “sliver” surfaces which may cause problems during meshing). Once the “Locator” identifies entities, you can then cycle through all of the located entities in the model one at a time and take action using the Geometry Tools in the Meshing Toolbox, when appropriate. Meshing Toolbox Icons Toggle Tools menu - By default, all 7 of the “tools” will be visible in the Meshing Toolbox. Mesh Quality Toggle Select Entity Entity Locator Remesh Modes Dialog Select Toggle Tools

Using the drop-down menu from this icon, you can make all of the tools visible or hidden at once using “Toggle All Tools”, individually toggle them on and off by choosing the individual “tool name” (for example, Feature Suppression) from the menu, or decide to show only one “set” of tools at a time by selecting the appropriate “tool set name” (for example, Geometry Tools). When a tool is visible, there will be a check mark next to it in the list. Here is a short description of each “set” of tools: Geometry Tools

•Feature Suppression - Basically, this tool allows you to use the same options available in the Mesh, Mesh Control, Feature Suppression command interactively. You may suppress loops (curves of internal holes on surfaces and solids, “base curves” of bosses and extrusions on solids), curves (usually relatively small in size), and surfaces (usually sliver surfaces, not fillets or chamfers). Suppressed geometry still exists in the model and can be “restored” at any time. See Section 7.2.2.1, "Feature Suppression Tool" •

Feature Removal - Most of the functionality in this tool, which is used to permanently remove geometric entities to simplify geometry, is offered in other FEMAP commands. This tool brings them together in one place where they can be used interactively. Removing “Loops” basically mimics the functionality of the Geometry, Surface, Remove Hole command, while removing “Surfaces” essentially uses the same process as Geometry, Solid, Remove Face. Finally, removing “Curves” uses portions of the Geometry, Solid, Cleanup command along some other methodology to try and remove redundant curves. In the case of “Aggressive Removal”, localized geometry around the selected curve may be slightly altered to accommodate the curve no longer being part of the geometry. See Section 7.2.2.2, "Feature Removal Tool"



Feature Editing - Used to make relatively basic alterations to Geometric “features”. Examples include modifying the position of a hole, boss, or rib, changing the length/width of an extrusion or entire part, revolving a face to create an angled wall or extending a revolved body, etc. Different operations require using the different Surface Selection Methods to select appropriate surfaces to be successful. Also, specifying a “realistic” translation or rotation vector is required. See Section 7.2.2.3, "Feature Editing"



Geometry Editing - This tool is used to “split” or otherwise modify curves or surfaces to create geometry for the purpose of producing a mesh with better quality elements. Curves can be modified using the same functionality found on the Modify, Break command, while Surfaces can be modified using the functionality from the bottom half of the Geometry, Curve - From Surface... menu and the Geometry, Midsurface, Extend command. See Section 7.2.2.4, "Geometry Editing"

Tools, Meshing Toolbox

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Combined/Composite Curves - In some cases, combining several smaller curves along the edge of a surface will allow you to create a higher quality mesh on the surface. This tool allows you to combine curves by choosing the curves themselves or a point that two curves share. A “Composite Curve” will be created in FEMAP, which will be used for mesh sizing purposes instead of the underlying curves. There are also options for splitting a “composite curve” at a selected point or removing any of the underlying curves. See Section 7.2.2.5, "Combined/Composite Curves Tool"



Combined/Boundary Surfaces - Much like creating “composite curves” to improve mesh quality, it may be a good idea to combine several surfaces into a “Boundary Surface”. This tool uses the same concept as the Geometry, Boundary Surface, From Surfaces on Solid command. This can be especially helpful when there are “sliver surfaces” next to a much larger surface. By combining the selected surfaces into one “boundary surface”, all of the internal curves can be ignored during the meshing process. “Boundary surfaces” can be created by selecting a curve shared by multiple surfaces or choosing the surfaces themselves. Also, any underlying surface can be removed from a boundary surface or “split” along a chosen curve. See Section 7.2.2.6, "Combined/Boundary Surfaces Tool"

Meshing Tools •

Mesh Sizing - Combines the options used to set mesh sizing and node spacing on curves (Mesh, Mesh Control, Size on Curve) with the “Add, Subtract, and Set To” functionality of the Mesh, Mesh Control, Interactive command. When using the Auto Remesh option in the Meshing Toolbox you will be able to see the mesh update “on the fly” after each change to sizing or node spacing, while you also monitor the element quality update (Mesh Quality Toggle “On”). There are also options for matching any number of selected curves to a “Master Curve”, as well as setting biasing and length based sizing without changing the number of elements on the curve. See Section 7.2.2.7, "Mesh Sizing Tool"



Mesh Surface - Allows surfaces to be meshed or remeshed “on-the-fly” using various surface meshing methods, options, and/or mesh approaches. Set or change options for Meshing Attributes, Property, Mesh Sizing, Element Shape, Meshing Method (Free or Mapped), Smoothing, Offsets, Quad/Tri Layers, and others. Choose Auto Mapped Approach or define approaches manually to quickly converge on a higher quality mesh. See Section 7.2.2.8, "Mesh Surface Tool"

Mesh Editing Tools •

Mesh Locate - There may be times when you would like to make small changes to an existing mesh simply by moving one or several nodes without changing the number of elements. This tool will allow you to do this while making sure that as you move the node or nodes dynamically, they remain attached to specified solid(s), surface(s), and curve(s), or if you have no geometry, follow the overall topology of the selected standalone mesh. There are also options to move the selected nodes by a defined amount, continually smooth the mesh as the nodes are moved, and allow the moved nodes to no longer be attached to surfaces or curves. Much like the Mesh Sizing tool, you can also turn on the Mesh Quality Toggle and monitor the element quality “real time” as the nodes are moved. See Section 7.2.2.9, "Mesh Locate Tool"



Mesh Quality - Creating a mesh with high quality elements is essential to the accuracy of a Finite Element model. When the Mesh Quality Toggle in the Meshing Toolbox is set to “on”, this tool allows you to graphically see an element quality value plotted on each element similar to a contour/criteria plot. There are several different element quality types which can be selected and each type has default automatic values, but user-defined values can also be specified. Also, the minimum and maximum quality values for the specified “quality type” are listed in the bottom fields of the tool. See Section 7.2.2.10, "Mesh Quality"

Entity Locator menu - The Entity Locator is very helpful in finding “Short Edges” and “Sliver/Small Surfaces” which may be causing meshing issues. It may also make it easier to locate “free edges” in troublesome geometry and mesh. This menu contains commands for toggling the Entity Locator on and off, cycling through the entities currently in the Entity Locator, removing the current entity from the Entity Locator or clearing it entirely, as well as creating a group from the entities currently in the Entity Locator or sending them to the Data Table. •

Toggle Entity Locator - When this icon is toggled “on”, the Entity Locator is ready to be filled with entities and the Locator fields will be available in the Meshing Toolbox. Depending on which entity type is selected in the Search For drop-down list, Curves or Surfaces, the Locator fields change. The Locate Options and Show Options can be used to modify how the Entity Locator searches for entities and then displays them. Also, the entities loaded in the Entity Locator update after each change made in the Locator fields, unless Auto Locate is turned “off” in the Locate Options section.

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Once entities are loaded into the Entity Locator, use the following commands to move from entity to entity. By default, the “current entity” in the Entity Locator will be “highlighted” in the graphics window using the display options currently set in the Style portion of the Windows, Show Entities command (See Section 6.3.2.3, "Window, Show Entities..."). There are other options for automatically rotating the model and zooming in to get a better view of the entity. See the Locate Options and Show Options sections in the Locator section for more information. •

Next - Makes the next entity in the Entity Locator the “current entity”.



Previous- Makes the previous entity in the Entity Locator the “current entity”.

Note: Once either Next or Previous has been selected, the icon will “persist” at the top of the Entity Locator menu in the Meshing Toolbox. This enables you to easily go to the “next” or “previous” entity simply by clicking the icon. When you reach the “last” entity in the Entity Locator, the Next icon will automatically become the Previous icon and vice versa. •

Current - “Re-highlights” the “current entity” in the Entity Locator. This can be helpful if you have regenerated or rotated the model.



First - Makes the “first” entity in the Entity Locator the “current entity”. When using Search Methods based on physical size, the smallest “located” entity will be the “first” entity.



Last - Makes the last entity in the Entity Locator the “current entity”. When using Search Methods based on physical size, the largest “located” entity will be the “last” entity.



Do Not Locate - Places the current entity into a group which is then automatically specified in the Not In Group field of the Locate Options.



Remove - Removes the current entity from the Entity Locator until cleared or new search criteria are entered.



Clear Locator - Simply clears the Entity Locator of all entities.



Create Group - Creates a new group with all of the entities currently in the Entity Locator or adds/removes/ excludes those entities from an existing group.



Add to Data Table - Adds all entities currently loaded in the Entity Locator to the Data Table. The Data Table needs to be “open” in the User Interface and “unlocked” for the command to be available. Search For - Indicates the entity type, Curves, Surfaces, or Elements the Entity Locator will currently be able to “locate” in the model. Depending on the entity type, different Locator fields become available. Locator fields and buttons when Search For is set to Curves: Search Method - Specifies the method the Entity Locator uses to “find, then load” itself with specific Curves in the model. Depending on the Search Method, other options may become available. Here are descriptions of the different Search Methods: •Short Edges - “Short edges” will be loaded into the Entity Locator using criteria specified in the current Based On option. When Based On is set to: Global Mesh Size - Curves whose length is shorter than the specified % of Mesh Size (default) will be loaded into the Entity Locator. Curve Length - Curves will only loaded into the Entity Locator which are Shorter Than a user-specified value. You may type the value in directly or specify the value by clicking the “Select Curve to Set Length” icon button, then choosing any curve on the screen. Shortest Curves - Finds the shortest “specified % of All Curves” in the model (For example, if set to 5, it will find the bottom 5% of curves, based on length) and loads them into the Entity Locator. This value can be set from 0 to 25 using the “slider bar” or a value

Tools, Meshing Toolbox

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can be entered directly (if value is higher than 25, loads all curves satisfying that criteria into the Entity Locator, then returns to 25). •

Free Edges - Locates all edges in a Solid which are not stitched to another surface. “Free Edges” in a Solid usually indicate “gaps” or “holes” in the geometry, meaning the Solid does not fully enclose a volume and is probably not viable for solid meshing (tet or hex). If multiple surfaces are “stitched” together but do not enclose a volume (Sheet Solid) or “joined” using the Geometry, Surface, NonManifold Add command (General Bodies), then “free edges” may also indicate “gaps” or “holes” between surfaces. Of course, “free edges” in this type of geometry may be internal holes/loops or the outside edge of the stitched/joined “part”, which are normal.

“Free Edges” of surfaces joined using “NonManifold Add” “Free Edges” of set of surfaces “Stitched” together



NonManifold Edges - Locates all “NonManifold” edges in the geometry. Only geometry that has been joined using the Geometry, Surface, NonManifold Add command (General Bodies) will have any of these edges. Typical “NonManifold Edges” are found where surfaces come together at “T-junctions” or a surface has been “NonManifold added” to a Solid. Two Examples of “NonManifold Edges”

Surfaces joined using “NonManifold Add”



Surface and Solid joined using “NonManifold Add”

From Group - Loads all Curves in a specified Group into the Entity Locator.

Show ‘#’ Curves button - By default, when you initially place Curves in the Entity Locator, ALL of the “found” Curves will be highlighted in the graphics window using the display options currently set in the Style portion of the Windows, Show Entities command (See Section 6.3.2.3, "Window, Show Entities..."). Like Windows, Show Entities and the “Show When Selected” capabilities of the Data Table and Model Info tree, once the view has been redrawn or regenerated the “highlighting” is removed and the view is restored to how it appeared before the “show” command. If you want to “highlight” the Curves again, simply click the Show ‘#’ Curves button. Locator fields and buttons when Search For is set to Surfaces: Search Method - Specifies the method the Entity Locator will use to “search and locate” specific Surfaces in the model. Depending on the Search Method, other options may become available. Here are descriptions of the different Search Methods: •

Surface Geometry - This method is used in conjunction with any combination of the Small Surfaces, Slivers, Spikes, and By Area options. If none of these options are turned on (checked), no surface geometry will be loaded into to the Entity Locator.

Small Surfaces (Fit In Radius value) - Surfaces which completely fit inside a sphere with a specified radius (defined by Fit In Radius value) will be loaded into the Entity Locator. Enter the Fit In Radius value directly or

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click the “Measure Distance” icon button to specify the sphere radius by picking two locations graphically. Default value is equal to the default Merge Tolerance in the model. Slivers (Sliver Tolerance value) - Surfaces which have high aspect ratios and small areas are known as “Slivers”. Examining a surface’s “maximum width” is often a good indication of whether a surface is a “sliver” or not. Surfaces with a “maximum width” smaller than the Sliver Tolerance will be loaded into the Entity Locator. Enter the Sliver Tolerance value directly or click the “Measure Distance” icon button and choose two locations graphically to specify a distance. Default value is equal to the default Merge Tolerance in the model. Spikes (Spike Width value) - Much like “slivers”, Surfaces with “spikes” also have high aspect ratio and small area. The main difference is that only a portion of the surface fits this criteria, not the entire surface. When this option is on and a “spike” on a surface is detected (smaller than Spike Width), FEMAP will try and remove the “spike”, while keeping the rest of the surface intact. Enter the Sliver Tolerance value directly or click the “Measure Distance” icon button and choose two locations graphically to specify a distance. Default value is equal to the default Merge Tolerance in the model. By Area (Area Less Than value) - Surfaces which have an Area Less Than the specified size will be loaded into the Entity Locator. Enter