Introduction to Thermal Analysis Using MSC.thermal

MSC.Software Corporation 2 MacArthur Place Tel: 714-540-8900 United States MSC.Patran Support Tel: 1-800-732-7284 Fax: 714-784-4343

Santa Ana, California 92707-5924 Fax: 714-784-4056 Tokyo, Japan Tel: 81-3-3505-0266 Fax: 81-3-3505-0914

Munich, Germany Tel: (+49)-89-43 19 87 0 Fax: (+49)-89-43 61 716

Introduction to Thermal Analysis Using MSC.Thermal PAT312 EXERCISE WORKBOOK MSC.Patran Version 2001

P3*V2001*Z*Z*Z*SM–PAT312–WBK

June 2001

PROPRIETARY NOTICE The MSC.Software Corporation reserves the right to make changes in specifications and other information contained in this document without prior notice. Although due care has been taken to present accurate information, THE MSC.SOFTWARE CORPORATION DISCLAIMS ALL WARRANTIES WITH RESPECT TO THE CONTENTS OF THIS DOCUMENT (INCLUDING WITHOUT LIMITATION WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE) EITHER EXPRESSED OR IMPLIED. THE MSC.SOFTWARE CORPORATION SHALL NOT BE LIABLE FOR DAMAGES RESULTING FROM ANY ERROR CONTAINED HEREIN, INCLUDING, BUT NOT LIMITED TO, FOR ANY SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF, OR IN CONNECTION WITH, THE USE OF THIS DOCUMENT. MSC.Patran is a registered trademark of The MSC.Software Corporation. MSC and MSC. are registered trademarks and service marks of The MSC.Software Corporation. ABAQUS is a registered trademark of Hibbitt, Karlsson, & Sorensen, Inc. ANSYS is a registered trademark of ANSYS, Inc. CADDS 5 and Computervision are trademarks of Computervision R&D Inc., a subsidiary of Prime Computer, Inc. CATIA is a registered trademark of Dassault Systemes. EUCLID is a registered trademark of Matra Datavision, S.A. IGES is an acronym for the “Initial Graphics Exchange Specification”, published by the U.S. Department of Commerce, National Institute of Standards and Technology. MARC is a registered trademark of MARC Analysis Research Corporation. Motif is a trademark of the Open Software Foundation, Inc. MSC.Nastran is an enhanced proprietary version developed, maintained, supported and marketed by The MSC.Software Corporation. NASTRAN is a registered trademark of the National Aeronautics and Space Administration. Pro/ENGINEER is a trademark of Parametric Technology Corporation. Unigraphics is a registered trademark of EDS Unigraphics Division. UNIX is a trademark of AT&T Bell Laboratories. X Window System is a trademark of the Massachusetts Institute of Technology. Training Documentation: Copyright ÿ 2001 The MSC.Software Corporation. All Rights Reserved. This notice shall be marked on any reproduction of this documentation, in whole or in part. Any reproduction or distribution of this document, in whole or in part, without the prior written consent of The MSC.Software Corporation is prohibited. If you would like to order more copies of this document, please contact MSC.Software Contracts Processing at (800) 400-4672. U.S.A. orders: All orders must be accompanied by a check or purchase order. Your order will be sent prepaid via UPS or fourth class mail and the shipping charges will be added to the invoice. F.O.B. will be the shipping point. Terms are net amount due within 30 days. Outside U.S.A. orders: Please contact your local MSC.Software office for a quotation.

DISCLAIMER The concepts, methods, and examples presented in this text are for educational purposes only and are not intended to be exhaustive or to apply to any particular engineering problem or design. The MSC.Software Corporation assumes no liability or responsibility to any person or company for direct or indirect damages resulting from the use of any information contained herein.

Printed in U.S.A. ©2001 by MSC.Software Corporation All rights reserved.

TABLE OF CONTENTS MSC.Patran Introduction to Thermal Analysis Using MSC.Thermal PAT312 Exercise Workbook Release 2001

Workshop

Title

Exercise 1

Construct Hybrid Microcircuit Geometry . . . . . . . . . . .1-1 Geometry Creation

Exercise 2

Hybrid Microcircuit Finite Elements. . . . . . . . . . . . . . . .2-1 Meshing

Exercise 3

Equivalence and Verify the Hybrid Mesh . . . . . . . . . . . .3-1 FEM Verification Tools

Exercise 4

Materials, Lists and Groups. . . . . . . . . . . . . . . . . . . . . . .4-1 Define material properties using lists and groups

Exercise 5

Thermal Analysis using Imported CAD Geometry . . . . .5-1 Create and analyze model with imported geometry

Exercise 6

Comparison of Two Heat Sink Designs . . . . . . . . . . . . .6-1 2D axisymmetric model with simple convection

Exercise 7

An Oven Window Design . . . . . . . . . . . . . . . . . . . . . . . .7-1 2D planar model with field definition for LBC, simple convection

Exercise 8

Temperature Dependent Material Properties. . . . . . . . . .8-1 2D planar model with field definition for material properties

Exercise 9

Thermal Analysis of the Hybrid Microcircuit . . . . . . . . .9-1 Create convection and loading LBCs, submit analysis and view results

Exercise 10

Time Dependent Boundary Conditions . . . . . . . . . . . . . .10-1 Using microfunctions for transient analysis

Exercise 11

Using Convection Correlations . . . . . . . . . . . . . . . . . . . .11-1 Using the convection correlation library Copyright ÿ 2001 MSC.Software

Workshop

Title

Exercise 12

Analysis of a Fuel Nozzle Tip . . . . . . . . . . . . . . . . . . . . .12-1 Advective, radiative and convective boundaries, convective quads

Exercise 13

A Sprinkler System Hydraulic Analysis . . . . . . . . . . . . .13-1 Pressure varying mass flow

Exercise 14

Midterm: Build a Simple 2 Plate Model . . . . . . . . . . . . .14-1 Radiation heat transfer, analysis utilities

Exercise 15

User Supplied Subroutines . . . . . . . . . . . . . . . . . . . . . . .15-1 User subroutine convection calculations

Exercise 16

A Concentric Tube, Counterflow Heat Exchanger . . . . .16-1 Element sweep, gap convection

Exercise 17

Analysis of a Fuel Nozzle Tip Using Convection Between Regions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17-1 Advective, radiative and convective boundaries

Exercise 18

Post-processing the Hybrid Microcircuit Results with Insight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18-1 Insight tools

Exercise 19

Animating Results with Insight . . . . . . . . . . . . . . . . . . . .19-1 Insight and Patran animation

Exercise 20

SINDA Translation of a PWB Model . . . . . . . . . . . . . . .20-1 Read session file, produce SINDA deck

Exercise 21

Optimizing Performance of Radiation Interchange Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . .21-1 Flags and settings to increase run efficiency

Exercise 22

Steady State Radiative Boundary Conditions . . . . . . . . .22-1 2D planar model with radiation within enclosures

Exercise 23

Your Model Here . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23-1 User initiated model

Copyright ÿ 2001 MSC.Software

WORKSHOP 1

Construct Hybrid Microcircuit Geometry 1 8

9

8

9

6

7

6

7

10 1 2 2

3 3

4 4

5 5

Y Z

X

Objective: ■

In this exercise you will construct a trimmed surface which will be the underlying geometry of a 3D Hybrid Microcircuit model.

■

Create a trimmed surface with interior cutouts for components.

■

Create regular surfaces representing component footprints.

MSC.Patran 312 Exercise Workbook - Release 2001

1-1

1-2

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 1

Construct Hybrid Microcircuit Geometry

Model Description: In this exercise you will create the required geometry for a 3D hybrid microcircuit model. You will first construct simple surfaces which will define the microcircuit perimeter and the locations of eight surface mounted devices. From the edges of these simple surfaces you will create chained curves which define the inner and outer edges (loops) of the microcircuit surface. From these chained curves you will create a trimmed surface, the guiding geometry of the microcircuit model. In later exercises you will define the finite element mesh, material properties, thermal loads, and boundary conditions for the microcircuit.

Exercise Overview: ■

Create a new database named microcircuit.db. Set the Tolerance to Based on Model, the Approximate Maximum Model Dimension to 0.02, and the Analysis Code to MSC/THERMAL.

■

Create a simple surface that will form the outside edge for the microcircuit model. The dimensions are provided.

■

Turn labels on using Tool Bar Show Labels icon.

■

Create eight regular surfaces that will define the locations of the surface mounted devices. The dimensions are provided.

■

Create chained curves on the edges of each surface by using Create/Curve/Chain.

■ ■

Unclutter the display by selectively hiding labels. . Complete the geometry of the hybrid microcircuit by using Create/Surface/Trimmed with the Option Planar.

■

Quit MSC.Patran.

MSC.Patran 312 Exercise Workbook - Release 2001

1-3

Hybrid Microcircuit Dimensions

Hybrid Microcirc uit

0.004

0.002

0.006 X 0.001 (typical) 0.0026

0.02

0.0094

0.002 X 0.002 (typical)

0.004

0.004

0.004

0.02

Figure 1 -Board Design

(All lengths shown in meters)

Exercise Procedure: Create a new database

1.

Create a new database named microcircuit.db. Set the Tolerance to Based on Model, the Approximate Maximum Model Dimension to 0.02, and the Analysis Code to MSC/THERMAL.

Within your window environment change directories to a convenient working directory. Run MSC.Patran by typing p3 in your xterm window. Next, select File from the Menu Bar and select New… from the drop-down menu. Assign the name microcircuit.db to the new database by clicking in the New Database Name box and entering microcircuit (.db will automatically be appended). Select OK to create the new database. 1-4

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 1

Construct Hybrid Microcircuit Geometry

MSC.Patran will open a Viewport and change various Control Panel selections from a ghosted appearance to a bold format. When the New Model Preferences form appears on your screen, set the Tolerance to Based on Model, the Approximate Maximum Model Dimension to 0.02, and the Analysis Code to MSC/THERMAL. Select OK to close the New Model Preferences form. 2.

Create a simple surface that will form the outside edge for the microcircuit model.

Select the Geometry toggle in Applications radio button. You will now create a 0.02 X 0.02 surface. Use its outside edges to form the outer loop for the trimmed surface you will create in the last part of this exercise.

Create a simple surface

Set the Action, Object, and Method to Create/Surface/ XYZ. Be sure to turn off Auto Execute in all forms in this exercise. Change the Vector Coordinates List to and select Apply to create the surface. The completed form is shown below. Geometry Action:

Create

Object:

Surface

Method:

XYZ

Surface ID List 1 Surface Type PATRAN 2 Convention

Refer. Coordinate Frame Coord 0 Vector Coordinates List Auto Execute Origin Coordinates List [0 0 0]

-ApplyMSC.Patran 312 Exercise Workbook - Release 2001

1-5

Turn on labels

3.

Turn on labels

Turn labels on using Tool Bar Show Labels icon.

Use the Tool Bar Show Labels icon on the menu bar to turn on labels. The correct model is shown below.

2

3

1

Y Z

4.

Position the 8 devices

X 1

4

Create eight regular surfaces that will define the locations of the surface mounted devices.

Position the left-most square device by changing the Vector and Origin Coordinates Lists to and [0.004 0.004 0]. Select Apply to create the surface.

1-6

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 1

Construct Hybrid Microcircuit Geometry

Create three copies of this region by changing the Action, Object, and Method to Transform/Surface/Translate. Enter for the Translation Vector and 3 for the Repeat Count. Click in the Surface List box. Select Surface 2 in the viewport. Select Apply to create the surface. The completed Geometry form and current model should appear as shown below. Geometry Action:

Transform

Object:

Surface

Method:

Translate

Surface ID List 3 Type of Transformation in Refer. CF ◆ Cartesian Curvilinear in Refer. CF ◆ ◆

2

3

Refer. Coordinate Frame Coord 0 Translation Vector

1

Translation Parameters Repeat Count 3 Delete Original Surfaces Auto Execute Surface List

6 7 10 11 14 15 18 19 3 4 5 2 5 8 9 1213 16 17 20

Y Z

X

1

4

Surface 2 -Apply-

Leaving the Action as Transform change the Object and Method to Point/Translate. Edit the Translation Vector to read and the Repeat Count to 1. Click in the Point List box and select Point 5 from the viewport, the lower left corner point of Surface 2. Select Apply to create the surface. Point 21 should appear to guide layout of the remaining four devices. MSC.Patran 312 Exercise Workbook - Release 2001

1-7

Position the 8 devices

Set the Action, Object, and Method to Create/Surface/ XYZ. Position the first rectangular device by changing the Vector Coordinates List to , clicking in the Origin Coordinates List box, and selecting Point 21 from the viewport. Select Apply to create the surface. After constructing Surface 6 use the Transform/ Surface/Translate operations twice to complete the remaining three device locations. Forms are shown below. Geometry

Geometry Action:

Create

Object:

Surface

Method:

XYZ

Surface ID List 6

Action:

Transform

Action:

Transform

Object:

Surface

Object:

Surface

Method:

Translate

Method: Translate Surface ID List 7

Surface ID List 8

Type of Transformation

Type of Transformation

in Refer. CF ◆ Cartesian Curvilinear in Refer. CF ◆ ◆

in Refer. CF ◆ Cartesian ◆ Curvilinear in Refer. CF ◆

Refer. Coordinate Frame Coord 0

Refer. Coordinate Frame Coord 0

Refer. Coordinate Frame Coord 0

Vector Coordinates List

Translation Vector

Translation Vector

Surface Type PATRAN 2 Convention

Auto Execute Origin Coordinates List Point 21 -Apply-

Translation Parameters Repeat Count 1 Delete Original Surfaces Auto Execute Surface List Surface 6 -Apply-

1-8

Geometry

MSC.Patran 312 Exercise Workbook - Release 2001

Translation Parameters Repeat Count 1 Delete Original Surfaces Auto Execute Surface List Surface 6 7 -Apply-

Construct Hybrid Microcircuit Geometry

WORKSHOP 1

Your model should now appear as shown below. 2

3

30

31

34

35

8

9

29 22

32 23

33 26

24

25

36 27

6

7

21

28

1

6

7

10

8

9

2 5

11

14

12

13

3

15

18

16

17

4

19 5 20

Y 1

Z

4

X

5.

Create chained curves on the edges of each surface.

In order to facilitate picking, use Preferences/Picking... and set Rectangle/Polygon Picking to Enclose entire entity. Select Close. Next, Change the Action, Object, and Method to Create/Curve/Chain. Turn off the Delete Constituent Curves option. To create the perimeter chain click in the Curve List box and then click in the Edge selection icon (third from the top) in the Select Menu. While holding the key down select the four outer edges of Surface 1. The completed form should now look like the one shown below. Geometry Action:

Create

Object:

Curve

Method:

Create chained curves

Chain

Curve ID List 1 Auto Chain... Delete Constituent Curves Curve List Surface 1.1 1.2 1.3 1.4

-Apply-

Select Apply to complete the function. MSC.Patran 312 Exercise Workbook - Release 2001

1-9

Unclutter the display

To create the 8 interior chained curves click in the Curve List box and drag a rectangle around Surface 2 (the lower left-most device location). The 4 edge identifiers for Surface 2 should replace the previous Curve List box entry. Select Apply to complete the function. Repeat this step for the remaining seven device surfaces. 6.

Unclutter the display

Unclutter the display by hiding some labels.

To simplify the displayed image of your model select Display from the Menu Bar and select Entity Color/ Label/Render... from the drop-down menu. When the Entity Color/Label/Render Display form appears select Hide All Entity Labels and turn on only Curve, Surface, and TSurf labels. Select Apply then Cancel to complete the function. Your model should now appear as shown below.

1 8

9

8

9 6

7

6

7

1 2 2

3 3

4 4

5 5

Y Z

X

7.

Create a trimmed surface

Complete the geometry of the hybrid microcircuit.

Create the trimmed surface that surrounds the microcircuits devices. Set Action, Object, and Method to Create/Surface/Trimmed. Select Option as Planar. Turn off the Delete Outer and Inner Loops switches. Click in the Outer Loop List databox, click in the Curve selection icon (second from the top) in the Select Menu and select 1-10

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 1

Construct Hybrid Microcircuit Geometry

Curve 1. Next, click in the Inner Loop List databox and drag a rectangle around Curves 2 through 9. The completed Geometry form is shown below for your reference. Geometry Action: Create Object:

Surface

Method:

Trimmed

Surface ID List 10 Surface Type PATRAN 2 Convention Option:

Planar

Auto Chain... Use All Edge Vertices Delete Outer Loop Outer Loop List Curve 1 Delete Inner Loops Inner Loop List Curve 2:9

-Apply-

Select Apply to complete the function. Your model should now appear as shown on the front panel of this exercise. If it does not, select Viewing from the Menu Bar and select Fit View from the drop-down menu. 8.

Quit MSC.Patran.

To stop MSC.Patran select File on the Menu Bar and select Quit from the drop-down menu.

MSC.Patran 312 Exercise Workbook - Release 2001

Quit MSC.Patr

1-11

Quit MSC.Patran

1-12

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 2

Hybrid Microcircuit Finite Elements

Objective: ■

■

In this exercise you will mesh the 3D Hybrid Microcircuit model in two steps. You will use both the IsoMesh and Paver mesher options to create a surface mesh. These surface elements will then be swept into solid elements.

MSC.Patran 312 Exercise Workbook - Release 2001

2-1

2-2

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 2

Hybrid Microcircuit Finite Elements

Model Description: In this exercise you will create a mesh for the 3D hybrid microcircuit model. You will use a finite element construction method called 2 1/2 D-meshing to create your 3D finite element model. This algorithm is an extension to the IsoMesh or Paver algorithms because it will create elements where no geometry exists. The mesh will be created in a two step process. First the surface geometry will be meshed using both the IsoMesh and Paver options. The resulting surface elements will be used as a template to create a solid mesh of hexahedral elements. Finally the quadrilateral surface elements are deleted.

Exercise Overview: ■

Open the existing database named microcircuit.db.

■

Using Show/Surface/Normal verify that all surface normals point in the +Z direction. If necessary, edit normals using Edit/Surface/Reverse.

■

Delete Surface 1 by using Delete/Any and selecting Surface 1.

■

Mesh the regions containing the devices using Create/Mesh/Surface and the IsoMesh Mesher.

■

Sweep/Element/Normal to create device hex elements.

■

Switch to the Paver Mesher and mesh the remaining trimmed surface geometry.

■

Sweep/Element/Normal with One Way Bias in the .- Z direction from all surface quads to create substrate hex elements.

■

Use Finite Elements/Delete/Any and the Select Menu filter to delete all surface quad elements.

■

Unclutter the display by hiding labels.

■

Quit MSC.Patran.

MSC.Patran 312 Exercise Workbook - Release 2001

2-3

Open an existing database

Exercise Procedure: Open an existing database

1.

Open the existing database named microcircuit.db.

Within your window environment change directories to the microcircuit.db working directory. Run MSC.Patran by typing p3 in your xterm window. Next, select File from the Menu Bar and select Open… from the drop-down menu. Select the name microcircuit.db from the Database List box.Select OK to open the database. MSC.Patran will open a Viewport and change various Control Panel selections from a ghosted appearance to a bold format. From the Menu Bar select Viewing/Named View Options... Select isometric_view then Close. Select Viewing/Fit View to readjust the display, if necessary. This will provide a convenient view for verifying normal vectors.

Verify surface normals

2.

Verify that surface normals point in the +Z direction.

Select the Geometry Applications radio button. Set the Action, Object, and Method to Show/Surface/Normal. Select Set Normal Vector Length and enter a Normal Vector Length of 0.01. Click in the Surface List box and drag a rectangle around all the displayed geometry. Select Apply. All normal vectors should point in the global +Z direction.

2-4

MSC.Patran 312 Exercise Workbook - Release 2001

Hybrid Microcircuit Finite Elements

WORKSHOP 2

If some surfaces have incorrect normal vectors use Edit/ Surface/Reverse in the Geometry form, as shown below, to point the normals in the +Z direction. Geometry Action:

Edit

Object:

Surface

Method:

Reverse

Reverse Associated Elements Auto Execute Surface List

Draw Normal Vectors Reset Graphics -Apply-

3.

Delete Surface 1.

Set the Action and Object to Delete/Any. Click in the Geometric Entity List box and select Surface 1 from the viewport. Use the shift-right mouse button to cycle pick between Surface 10 and Surface 1 or select Surface 1 from the Selection list window, if necessary. Select Apply to delete Surface 1. Repaint the screen with the Refresh Graphics paint brush icon.

MSC.Patran 312 Exercise Workbook - Release 2001

Delete Surface 1

2-5

IsoMesh device regions

4.

IsoMesh device regions

Mesh the device regions with an IsoMesh.

Select the Finite Elements Applications radio button. Set the Action, Object, and Type to Create/Mesh/Surface. Set the Global Edge Length to 0.0012. Click in the Surface List box and while holding down the key select the eight interior device surfaces with the left mouse button. The completed form is shown below.

Finite Elements Action:

Create

Object:

Mesh

Type:

Surface

Output IDs Node ID List 1 Element ID List 1 Global Edge Length 0.0012 Element Topology Quad4 Quad5 Quad8

8

6

6

1 9

9

7

7

10 2

2

Mesher

Y

◆Paver ◆IsoMesh◆

8

Z

3

3

4

4

5

5

X

IsoMesh Parameters... Node Coordinate Frames...

Surface List Surface 2:9 -Apply-

Select Apply to complete the meshing function. The display should appear as shown above. If it does not, select the undo icon and analyze the error to a resolution. 2-6

MSC.Patran 312 Exercise Workbook - Release 2001

Hybrid Microcircuit Finite Elements

WORKSHOP 2

5.

Create device hex elements.

Set the Action, Object, and Method to Sweep/Element/ Normal. (If the Mesh Control form appears click OK to accept the defaults.) Change the Normal Length to 0.001. Click in the Base Entity List box and drag a rectangle around the eight sets of quad elements. Select Apply to complete the meshing function. The completed form and resultant display are shown below.

Create device hex elements

Finite Elements Action: Object: Method:

Sweep Element Normal

Output IDs Element ID List 37 Node ID List 85

1

8 6

FE Parameters... Mesh Control... Normal Length 0.001

9 7

10 2

Offset 0.0

Y

Reverse Normal Direction Delete Original Elements

Z

3

4

5

X

Base Entity List Elm 1:36

-Apply-

6.

Mesh the remaining trimmed surface with Paver.

Set the Action, Object, and Method to Create/Mesh/ Surface. The Global Edge Length should be set to 0.0012. Select Paver as the Mesher option. Click in the Surface List box and select the remaining unmeshed trimmed surface, Surface 10. Select Apply to complete the function. If you experience any problems selecting Surface 10, use Preferences/Picking.../(Single Picking) Centroid. MSC.Patran 312 Exercise Workbook - Release 2001

Create the substrate Paver

2-7

Create the substrate hex mesh

7.

Create the substrate hex mesh

Sweep a one-way-biased mesh of hex elements in the - Z direction from all surface quads.

Set the Action, Object, and Method to Sweep/Element/ Normal. (If the Mesh Control form does not appear click on Mesh Control...) In the Mesh Control form change the Method to One Way Bias set Number to 3 and L2/L1 to 4. Select OK to close the Mesh Control form. In the Finite Elements form set Normal Length to 0.005 and turn on Reverse Normal Directions. Click in the Base Entity List box and drag a rectangle around all of the elements in the viewport. (The default Select Menu filter will allow selection of only the quad/tri elements.) The form should appear as shown below. Mesh Control

Finite Elements Action: Object: Method:

Sweep Element Normal

Method: One Way Bias

Mesh Control Data L1

Output IDs Element ID List 400 Node ID List 611

L2

◆ Num Elems and L2/L1 ◆ L1 and L2 ◆ Number = 3 L2/L1 =

4

FE Parameters...

OK

Mesh Control... Normal Length 0.005 Offset 0.0

1

8 6

Reverse Normal Direction

9 7

Delete Original Elements

10

Base Entity List Elm 1:36 109:424

2

3

4

5

Y

-Apply-

Z

X

Select Apply to complete the meshing function. The resultant display is shown above. 2-8

MSC.Patran 312 Exercise Workbook - Release 2001

Hybrid Microcircuit Finite Elements

WORKSHOP 2

8.

Delete all surface quad elements.

In the Finite Elements form set Action and Object to Delete/Any.

Delete all quad elements

Click in the Finite Element Entity List box. In the Select Menu choose the quad element filter icon (third from the top), in the second level Select Menu choose the quad element filter (fifth from the top), and drag a rectangle around all entities displayed in the viewport. The form should now appear as shown below.

Finite Elements Action: Object:

Delete Any

Delete Node and Related Empty Groups Element and Related Node Empty Groups MPC's Node Empty Groups Auto Execute Finite Element Entity List Elm 1:36 109:424

-Apply-

Select Apply to complete the function.

MSC.Patran 312 Exercise Workbook - Release 2001

2-9

Unclutter the display

Unclutter the display

9.

Unclutter the display by hiding labels.

To simplify the display of your model select Display from the Menu Bar and select Plot/Erase... from the drop-down menu. When the Plot/Erase form appears select Posted Entities/Geometry:Erase. Select OK to close the form. Select Display from the Menu Bar and select Entity Color/Label/Render… from the drop-down menu. When the Entity Color/Label/Render form appears select Hide All Entity Labels. Click in the Render Style: box and select Hidden Line or use Hide Labels and Hidden Line icons shown to the right. Select Apply then Cancel to complete the function.

Your model should now appear as shown on the front panel of this exercise. Reset the Render Style to Wireframe.

Quit MSC.Patr

2-10

10.

Quit MSC.Patran.

Select File on the Menu Bar and select Quit from the dropdown menu.

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 3

Equivalence and Verify the Hybrid Mesh

Y Z

X

Objective: ■

■

In this exercise you will equivalence the 3D Hybrid Microcircuit model mesh. You will sample the finite element verification functions to examine the aspect ratio, skewness, and taper of the mesh elements.

MSC.Patran 312 Exercise Workbook - Release 2001

3-1

3-2

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 3

Equivalence and Verify the Hybrid Mesh

Model Description: The hybrid microcircuit is monolithic: all material interfaces have negligible resistance to heat transfer. Hence, there are no contact resistances modeled in the structure and the entire model is materially continuous. In this exercise you will identify any incongruities, “cracks”, in the finite element mesh and equivalence to eliminate them. You will examine the completed mesh with quantitative verification tools. You will evaluate the mesh element aspect ratio, taper, and skewness. These are generally useful in qualitatively assessing the accuracy of results and identifying problem areas for convergence to a solution.

Exercise Overview: ■

Open the existing database named microcircuit.db.

■

Use Finite Element/Verify/Element/Boundaries to identify any “cracks” which remain as artifacts from the geometry creation and meshing process.

■

Equivalence/All/Tolerance Cube to eliminate duplicate nodes and eliminate “cracks” in the mesh.

■

Verify/Hex/Aspect to identify elements with aspect ratios greater than 3.0.

■

Verify/Hex/Face Skew to identify elements with face skew angles greater than 110 degrees.

■

Verify/Hex/Face Taper to identify elements with highly tapered faces.

■

Quit MSC.Patran.

MSC.Patran 312 Exercise Workbook - Release 2001

3-3

Open an existing database

Exercise Procedure: Open an existing database

1.

Open the existing database

Within your window environment change directories to the microcircuit.db working directory. Run MSC.Patran by typing p3 in your xterm window. Next, select File from the Menu Bar and select Open... from the drop-down menu. Select the name microcircuit.db from the Database List box. Select OK to open the database. MSC.Patran will open a Viewport and change various Control Panel selections from a ghosted appearance to a bold format. 2.

Identify cracks in mesh

Identify any “cracks” which remain as artifacts from the geometry creation and meshing process.

To identify mesh boundaries select the Finite Elements Applications radio button. Set the Action, Object, and Test to Verify/Element/Boundaries. Select Apply. The display should appear as shown below.

Y Z

Equivalen ce mesh nodes

3-4

3.

X

Equivalence nodes to eliminate duplicate nodes and eliminate “cracks” in the mesh.

Set the Action, Object, and Method to Equivalence/All/ Tolerance Cube. Select Apply to complete the function. MSC.Patran 312 Exercise Workbook - Release 2001

Equivalence and Verify the Hybrid Mesh

WORKSHOP 3

The nodes bounding the interior cracks will be circled in the display and the Command Line will indicate that a number of nodes are deleted. Reexamine the mesh boundaries after equivalencing with Verify/Element/Boundaries. Your model should appear as shown on the front panel of this exercise. 4.

Identify elements with aspect ratios greater than 3.0.

In the Finite Elements form set the Action, Object, and Test to Verify/Hex/Aspect. Change the Aspect Ratio to approximately 3.0. Select Apply. Since the paver mesher was used your results may vary from those shown below. Now select Plot Failed Elements Only. The completed form and resultant display are shown below.

Evaluate element aspect

Finite Elements Verify

Action:

Hex

Object:

Aspect

Type:

Reliability Threshold h1 h2

h2 h1

Normalize Analysis Code: MSC/THERMAL 0.

20.

3.07

Aspect Ratio Element Plot Options Color Code Elements Plot Failed Elements Only

Fringe Attributes... Reset Graphics

Apply

Reset

MSC.Patran 312 Exercise Workbook - Release 2001

3-5

Evaluate element face skewness

MSC.Thermal is reliable in converging to a solution even with elements of relatively high aspect ratio. However it is left to the analyst to decide whether too large a gradient is resolved across the long dimension of a high aspect ratio element. If this is so then resolving the mesh to a lower aspect ratio in that area will yield more accuracy.

Evaluate element face

5.

Identify elements with face skew angles greater than 110 degrees.

In the Finite Elements form set the Action, Object, and Test to Verify/Hex/Face Skew. Change the Face Skew Angle to approximately 20.0. Select Apply. Since the paver mesher was used your results may vary from those shown below. Now select Plot Failed Elements Only. The completed form and resultant display are shown below. Finite Elements Verify

Action:

Hex

Object: Type:

Face Skew

Reliability Threshold α

×°-α) (90

Normalize Analysis Code: MSC/THERMAL 0.

90.

20.05

Face Skew Angle Element Plot Options Color Code Elements Plot Failed Elements Only Fringe Attributes... Reset Graphics Apply

3-6

Reset

MSC.Patran 312 Exercise Workbook - Release 2001

Equivalence and Verify the Hybrid Mesh

WORKSHOP 3

The finite element formulation of an R-C network in MSC.Thermal has been developed to provide a higher order accuracy to the resultant temperature distribution than is available with the traditional lumped mass/element centroid technique. Hence, even meshes with skewed elements yield results which do not contain artifacts of the mesh geometry. 6.

Identify elements with highly tapered faces.

In the Finite Elements form set the Action, Object, and Test to Verify/Hex/Face Taper. Change the Face Taper to approximately 0.90. Select Apply. Since the paver mesher was used your results may vary from those shown below. Now select Plot Failed Elements Only. The completed form and resultant display are shown below.

Evaluate element face taper

Finite Elements Verify

Action:

Hex

Object: Typet:

Face Taper

Reliability Threshold

4a A

a

Normalize Analysis Code: MSC/THERMAL 0.

.90

1.

Face Taper Element Plot Options Color Code Elements Plot Failed Elements Only Fringe Attributes... Reset Graphics Apply

Reset

MSC.Patran 312 Exercise Workbook - Release 2001

3-7

Quit MSC.Patran

The verification functions in MSC.Patran provide a tool for quantifying the geometric quality of a finite element mesh. The criteria which determine the performance of the mesh in a numerical analysis remain the province of the analyst and his or her experience with the particular analysis. Click Reset Graphics in the Finite Elements Verify form.

Quit MSC.Patr

3-8

7.

Quit MSC.Patran.

To stop MSC.Patran select File on the Menu Bar and select Quit from the drop-down menu.

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 4

Materials, Lists, and Groups

Objective: ■

■

In this exercise you will define material properties and apply them as element properties on the hybrid microcircuit mesh. You will also use lists and groups as tools to more easily manipulate your model.

MSC.Patran 312 Exercise Workbook - Release 2001

4-1

4-2

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 4

Materials, Lists, and Groups

Model Description: In this exercise you will define several groups which will contain subsets of model entities. These groups can facilitate model manipulation. You will define materials by entering the data manually based on the information provided These materials will be applied as element properties. Lists will be used to demonstrate their utility in completing the application and verification of element properties. As you progress, carefully review your steps to ensure that you have repeated each step, if necessary, for each material, group, and property definition.

Exercise Overview: ■

Open the existing database named microcircuit.db.

■

Use Create//Isotropic/Manual Input to define the five materials used in this model.

■

Use Group/Create to define a group containing only geometry, another containing only FEM entities, and two more groups dividing the substrate FEM and the device FEM.

■

Use Properties/Create/3D/Thermal 3D Solid to apply the material properties to 4 of the 5 material regions; intentionally ignore the silicon region.

■

Use List/Create... and List/Boolean...to identify elements which have not had a material property . applied.

■

Complete application of material properties using the ‘listc‘ contents as input.

■

Quit MSC.Patran.

MSC.Patran 312 Exercise Workbook - Release 2001

4-3

Hybrid Microcircuit Materials

Hybrid Microcirc uit Figure 1-Material Location

A B C

D

E

A B

Substrate Layers Devices & Solder

Table 1-Material Information Material

(A) (B) (C) (D) (E)

4-4

Silicon Solder Alumina Molybdenum Kovar

MSC.Patran 312 Exercise Workbook - Release 2001

Conductivity (w/m-C) 148.0 35.7 30.1 139.0 13.9

Materials, Lists, and Groups

WORKSHOP 4

Exercise Procedure: 1.

Open the existing database

Within your window environment change directories to the microcircuit.db working directory. Run MSC.Patran by typing p3 in your xterm window.

Open an existing database

Next, select File from the Menu Bar and select Open… from the drop-down menu. Select the name microcircuit.db from the Database List box. Select OK to open the database. MSC.Patran will open a Viewport and change various Main Form selections from a ghosted appearance to a bold format. 2.

Define the five materials used in this model.

Define a material by selecting the Materials Applications radio button. Set the Action, Object, and Method to Create/Isotropic/Manual Input. Enter the Material Name Silicon and select Input Properties... to enter the data. In the Input Options form enter the value provided in Table 1 for Thermal Conductivity. Enter 1.0 for Density and Specific Heat; these are inert values which are required in the form but not used in a steady-state analysis. The completed form should look as follow.

MSC.Patran 312 Exercise Workbook - Release 2001

Define materials

4-5

Define materials

Input Options Constitutive Model:

Materials Action:

Thermal Properties

Property Name

Object:

Value

Thermal Conductivity =

148.0

Density =

1.0

Specific Heat =

1.0

Method:

Create Isotropic Manual Input

*

Filter

Existing Materials

[Phase change temperature] [Latent Heat] =

Time, Temperature or Constant Fields: Material Name Silicon Description Date: 15-Nov-95 Time: 09:48:33

Current Constitutive Models:

Code: MSC/THERMAL -Apply-

Clear

Cancel

Type: Thermal Input Properties... Change Material Status...

Select Apply to define the material. Without closing the Input Options form edit the Material Name and repeat the steps for the remaining four materials renaming them appropriately, Solder, Alumina, Molybdenum, and Kovar. Each time enter the correct thermal conductivity without changing the density or the specific heat. Hit Apply with completion of each material. Select Cancel to close Input Options. After completing the material definitions deselect the Material Application radio button.

4-6

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 4

3.

Materials, Lists, and Groups Divide the geometry and FEM into working groups.

Select Group from the Menu Bar and select Create… from the drop-down menu. Click in the New Group Name box and enter hybrid_geom; click in the Group Contents: menu and select Add All Geometry. The completed form is shown below.

Define geometry and FEM groups

Group Create Action:

Create

Current Viewport default_viewport

Filter

*

Existing Group Names default_group

New Group Name hybrid_geom Make Current Unpost All Other Groups Group Contents: Add All Geometry -Apply-

Cancel

Select Apply to complete the function. Reselect Group/Create, if necessary. Click in the New Group Name box enter hybrid_fem click in the Group Contents: menu and select Add All FEM. Turn on Unpost All Other Groups. Select Apply to complete the function. From the Menu Bar select Viewing/Named View Options... Select side_view then Close. Select Viewing/ Fit View to readjust the display. This is a convenient view for creating the next two groups.This can also be accomplished using the Tool Bar Right Side View icon.

MSC.Patran 312 Exercise Workbook - Release 2001

4-7

Define geometry and FEM groups

Reselect Group/Create, if necessary. Click in the New Group Name box enter substrate_fem. Click in the Group Contents: menu and select Add Entity Selection. Turn off Make Current, Posted, and Unpost All Other Groups. From the Select Menu select the Select any FEM entity filter, third icon from the top; from the next level Select Menu select the Element filter, also third from the top; finally, in the third level Select Menu select the Hex element filter, eighth from top. Drag a rectangle around the perimeter of the substrate selecting only the 3 layers of substrate hex elements. The form is shown below. Group Create Action:

Create

Current Viewport default_viewport Filter

*

Existing Group Names default_group hybrid_geom hybrid_fem

New Group Name substrate_fem Make Current Posted Unpost All Other Groups Group Contents: Add Entity Selection

Entity Selection Elm 425:1480

-Apply-

Cancel

Select Apply to complete the function. Repeat these steps dragging a rectangle around only the device area and solder to create the last group named device_and_solder. After all groups are defined, Cancel the Group Function.

4-8

MSC.Patran 312 Exercise Workbook - Release 2001

Materials, Lists, and Groups

WORKSHOP 4

4.

Apply the material properties to 4 of the 5 material regions; intentionally ignore the silicon region.

Select the Properties Applications radio button. Set the Action, Dimension, and Type to Create/3D/Thermal 3D Solid. Enter Property Set Name prop_kovar. Select the Input Properties... box. In the Input Properties form, click in the Material Name box and select Kovar from the Material Properties Sets list. Select OK to close the form.

Apply element properties

Click in the Select Members box. From the at the bottom of the screen select the Select a Solid element filter, second icon from the top, and drag a rectangle around the lowest layer of hex elements, region E in Figure 1. The completed form is shown below. Select Add then Apply to complete the function. Element Properties

Input Properties

Action:

3D SOLID Property Name

Value

Material Name

m:Kovar

Value Type

Create

Dimension: 3D Type:

Thermal 3D Solid

Mat Prop Name

[Material orient.-X]

Real Scalar

[Material orient.-Y]

Real Scalar

[Material orient.-Z]

Real Scalar

Existing Property Sets

Property Set Name

prop_kovar Option(s): FE hex, tet, wedge

Material Property Sets

Input Properties...

Silicon Solder Alumina Molybdenum Kovar

Application Region Select Members

Elm 1129:1480 Add

OK

Remove

Application Region

-Apply-

Repeat these steps for the next three layers of elements naming the properties prop_moly, prop_alumina, and prop_solder. Be certain to select the appropriate material for each layer. Omit assigning element properties to the silicon devices. Refer to Figure 1 for material locations. MSC.Patran 312 Exercise Workbook - Release 2001

4-9

Using lists to find elements

We are intentionally omitting the application of a material property to some elements. However, it is not unusual in practice to inadvertently omit assigning an element property to some elements. Use lists to recover them. 5.

Using lists to find

Identify elements which do not have a material property applied.

Select Tools from the Menu Bar and select List from the drop-down menu and Create… from the submenu. Set the Model, Object, and Method to FEM/Element/ Association. In the Association frame scroll to and select Group. In the Existing Groups frame select hybrid_fem. Select Apply. All elements will be listed in ‘lista‘ contents:. Find Target List at the bottom of the Create List form select “B”. Set the Model, Object, and Method to FEM/Element/ Attribute. In the Attribute list select Material. In the Existing Materials list drag through all listed materials and select all materials. Select Apply. Elements with defined materials are listed in ‘listb‘ contents:. The resulting forms are shown below. Model:

Create List FEM

Element Object: Method: Association Association Surface Face Solid Node Group

List A `lista` contents: Element 37:108 425:1480

Method:

Add To Group... Remove From Group...

Filter Specification *

Highlight

Clear

Previous

Cancel

Element 37:72 425:1480

Remove From Group...

◆ ◆ “B” ◆

Apply

4-10

Cancel

Attribute Select Property Set Material Fringe Value Filter Specification * Existing Materials

List B `listb` contents:

Add To Group... Target List “A”

Attribute

Filter

Filter Existing Materials default_group device_fem hybrid_fem hybrid_geom substrate_fem

Create List FEM Model: Element Object:

Highlight

Clear

Previous

Cancel

MSC.Patran 312 Exercise Workbook - Release 2001

Silicon Solder Alumina Kovar

Target List

◆ “A” ◆ ◆ “B” Apply

Cancel

Materials, Lists, and Groups

WORKSHOP 4

Since Lista A contains all elements and List B contains all elements with a material attribute, subtracting List B from List A will yield List C which will contain all elements which do not have material attributes. Select Tools/List from the Menu Bar and select Boolean… from the submenu. The Boolean List form will offer several options for Boolean operations, choose the AB icon. The variable ‘listc‘ now contains the desired element list. Select Cancel to exit the Boolean List and select Cancel again to exit the Create List form. The contents of ‘lista‘, ‘listb‘, and ‘listc‘ are retained. MSC.Patran supplies a set of utilities collected under the name Utilities. When installed, Utilities provides a utility, Utilities/Group/Group Elements with No Properties..., which accomplishes the preceding steps in three mouse clicks. We will discuss and use Utilities in later lectures and exercises. 6.

Complete application of material properties using the ‘listc‘ contents as input.

To complete element properties return to Create/3D/ Thermal 3D Solid. Input the Property Set Name prop_silicon. Complete the Input Properties form by selecting Silicon from the Material Property Sets. In the Select Members box type ‘listc‘ (use reverse apostrophes). Notice that ‘listc‘ is evaluated in the Application Region. Select Add then Apply to complete the function.

Complete the element

From the Menu Bar select Viewing/Named View Options... from the drop-down menu. Select isometric_view then Close. Or use Tool Bar Iso 1 View icon.

In the Element Properties form set Action as Show, in Existing Properties select Material Name, and in Display Method select Scalar Plot. Select Groups as hybrid_fem and select Apply. The model should now appear as on the front panel of the exercise. 7.

Quit MSC.Patran

To stop MSC.Patran select File on the Menu Bar and select Quit from the drop-down menu. MSC.Patran 312 Exercise Workbook - Release 2001

Quit MSC.Patr 4-11

Quit MSC.Patran

4-12

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 5

Thermal Analysis using Imported CAD Geometry

Objective: ■

In this exercise you will complete a thermal analysis of a model created from imported CAD geometry.

MSC.Patran 312 Exercise Workbook - Release 2001

5-1

5-2

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 5

Thermal Analysis using Imported Geometry

Model Description: In this exercise analyze an oven lid clamp. The clamp geometry (in centimeters) will be imported as ProEngineer geometry; from it, create a Brep solid. Use the Auto TetMesh Mesher to mesh the solid. Apply boundary conditions, complete the analysis and review the results. This stainless steel (MID 364) clamp is used to clamp the perimeter flange on a pressurized processing oven lid. The oven lid surface can reach 300oC for several days. The lid is insulated; the insulation is sometimes pierced by the clamp edge. The clamp mounting boss is fastened with two bolts and thermal grease (total contact h = 0.01 w/oC-cm2) to a room temperature (20oC) water cooled sink. Determine both that the bracket mounting boss will remain at or below 50oC to ensure safe handling during disassembly and that the spring tab knee and boss transition areas remain at or below 150oC to prevent loss of clamping force due to creep. This exercise will introduce a different format for guiding data entry, keystrokes, and mouse operations. Though all actions and entries required to accomplish a given step are provided some additional synthesis may be required by the user since exact images of the entry forms are not provided.

Exercise Overview: ■

Open a new database named exercise_05.db.

■

Import Pro/ENGINEER primitive geometry from a file named oventab.geo.

■

Create a B-rep solid from these surfaces and delete the original surfaces in the process.

■

Mesh the solid with the TetMesh Mesher using Tet4 elements, a global edge length of 2.5..

■

Define an element property over all the solid elements using a material name of 364.

■

Create a boundary sink node 999 below the mounting boss and not associated with geometry.

■

Change the view for application of boundary conditions

■

Apply a 20oC fixed temperature to the sink node.

■

Apply a fixed temperature of 300oC to the edge of the solid in contact with the lid. MSC.Patran 312 Exercise Workbook - Release 2001

5-3

Open a new database ■

Apply a convection boundary condition of 0.01 w/oCcm2 to the underside of the mounting boss.

■

Select the mpidcgs.bin file in the P/Thermal Translation Parameters form in order to select the correct material property units.

■

Run the analysis and read the results into the database.

■

Fringe plot the temperature results and evaluate them against the requirements.

■

Quit MSC.Patran.

Exercise Procedure: Open a new database

1.

Open a new database named exercise_05.db.

Within your window environment change directories to a convenient working directory. Run MSC.Patran by typing p3 in your xterm window. Next, select File from the Menu Bar and select New … from the drop-down menu. Assign the name exercise_05.db to the new database by clicking in the New Database Name box and entering exercise_05 (.db will automatically be appended). Select OK to create the new database. File New... New Database Name

exercise_05

OK MSC.Patran will open a Viewport and change various Control Panel selections from a ghosted appearance to a bold format. When the New Model Preferences form appears on your screen, set the Tolerance to Default, and the Analysis Code to MSC/THERMAL. Select OK to close the New Model Preferences form. Tolerance

◆ Default

Analysis Code

MSC/THERMAL

OK 5-4

MSC.Patran 312 Exercise Workbook - Release 2001

Thermal Analysis using Imported Geometry

WORKSHOP 5

2.

Import Pro/ENGINEER primitive geometry from a file named oventab.geo.

Select File from the Menu Bar and select Import… from the drop-down menu. Change the Object, Source, and File Type list boxes as shown below. It may be necessary to select a path and use the Filter button to locate the oventab.geo file which should be contained in your home directory.

Import CAD geometry

File Import... Object

Model

Source

Pro/ENGINEER

File Type

Primitive Geometry

Pro/ENGINEER Files

oventab.geo

Apply The model geometry will be imported. A Pro/ENGINEER Model Import form will provide statistics on the entity type and quantity imported. Click OK to close this form.

Summary

OK The display should appear as shown below.

MSC.Patran 312 Exercise Workbook - Release 2001

5-5

Import CAD geometry

Select Viewing from the Menu Bar or use the Tool Bar Iso 1 View con to change to an isometric_view. Preference Graphics... Auto Fit View

Apply Cancel Viewing Named View Options... Select Named View

isometric_view

Close Or, use the Tool Bar Iso 1 View Icon.

The model should appear as shown below.

Y Z

5-6

X

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 5

3.

Thermal Analysis using Imported Geometry Create a B-rep solid from these surfaces and delete the original surfaces in the process.

Create a Brep solid

Select the Geometry Applications radio button. Create a B-rep solid using the following Action, Object, and Method.

◆ Geometry Create/Solid/B-rep Delete Original Surfaces Auto Execute Surface List



Apply A message window will request confirmation of deletion. Select Yes. Yes B-rep solid 1 is displayed as white in the viewport.

4.

Mesh the solid with the TetMesh Mesher using Tet4 elements, a global edge length of 2.5.

Select the Finite Elements Applications radio button. Set the Action, Object, and Type to Create/Mesh/Solid. The Isomesh Mesher is used on regular parametric solids. In order to mesh this B-rep solid use the TetMesh Mesher. Use the default Tet4 topology and adjust the Global Edge Length and TetMesh Parameters to reduce the mesh resolution for this analysis.

TetMesh the B-rep solid

◆ Finite Elements Create/Mesh/Solid Global Edge Length

2.5

Mesher

◆ TetMesh

Input List



Apply

MSC.Patran 312 Exercise Workbook - Release 2001

5-7

Apply element properties to the elements

Your model should appear as shown below.

Y Z

Apply element properties to the

5.

X

Define an element property over all the solid elements using a material MID of 364.

Select the Properties Applications radio button. Set the Action, Dimension, and Type to Create/3D/Thermal 3D Solid. In the Input Properties form enter an MID of 364 for the Material Name and select Solid 1 as the Select Member region.

◆ Properties Create/3D/Thermal 3D Solid Property Set Name

Stainless_steel

Input Properties... Material Name

364

OK Select Members



Add Apply

5-8

MSC.Patran 312 Exercise Workbook - Release 2001

Thermal Analysis using Imported Geometry

WORKSHOP 5

6.

Create a boundary sink node 999 below the mounting boss and not associated with geometry.

Select the Finite Elements Applications radio button. Create a boundary node which is not associated with geometry. The node is numbered 999. Locate the node at [0 -5 0] centered below the mounting boss.

Create a boundary sink node

◆ Finite Elements Create/Node/Edit Node ID List

999

Associate with Geometry Node Location List

[0 -5 0]

Apply

7.

Increase node display size and change the view to a Y-Z, side_view. Rotate the view to show the bottom surface of the mounting boss.

Increase the display size of nodes to facilitate the application of boundary condition. Use either Display/Finite Elements... or the associated Tool Bar icon to change the node size.

Increase node size and change to

Display Finite Elements... Node Size (use slider bar)

6

Apply Cancel Select Viewing from the Menu Bar to change to a side_view of the model. Alternately, this step can be completed using the Tool Bar Right Side View icon. Viewing Named View Options... Select Named View

side_view

Close

MSC.Patran 312 Exercise Workbook - Release 2001

5-9

Increase node size and change to a Y-Z view

Using Viewing/Transformations... from the drop down menu to change the view point by tilting the 15o around the -Z axis to show the bottom surface of the mounting boss. Viewing Transformations... Options... Rotation increment (deg)

15

OK

OK The model should appear as shown below. Note location of Node 999.

Node 999

5-10

MSC.Patran 312 Exercise Workbook - Release 2001

Thermal Analysis using Imported Geometry

WORKSHOP 5

8.

Fix the boundary node temperatures at 20.0 oC.

Begin applying boundary conditions. Select the Loads/BCs Applications radio button. Create a fixed 20.0oC nodal boundary named Sink.

Fix nodal boundary temperature

◆ Loads/BCs Create/Temperature/Nodal Option:

Fixed

New Set Name

Sink

Input Data... In the Input Data form define the fixed temperature. 20.0

Fixed Temperature

OK Select Application Region... In the Select Applications Region form pick node 999.

◆ FEM

Select Nodes

Add OK Apply In order to facilitate applying the next two boundary conditions change the display. Select Display then Entity Color/Label/Render ... Change Render Style to Shaded/Flat or use the Tool Bar Smooth Shaded icon to affect the change. Display Entity Color/Label/Render... Render Style

Shaded/Flat

Apply Cancel

MSC.Patran 312 Exercise Workbook - Release 2001

5-11

Fix nodal boundary temperature

The display should appear as shown below. The lower contact edge of the spring tab, and the bottom of the mounting boss should now be visible.

Lower spring tab edge Bottom of mounting boss

Apply the fixed edge temperature. Enter a New Set Name Edge with a fixed temperature of 300.0oC applied to lower edge of the spring tab. New Set Name

Edge

Input Data... Fixed Temperature

300.0

OK Select Application Region...

◆ Geometry Select Geometry Entities



Add OK Apply 5-12

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 5

Thermal Analysis using Imported Geometry

The display should highlight each node and append the fixed temperature. On some displays the symbol and value may be difficult to discern.

9.

Apply contact heat transfer coefficient.

Create the contact heat transfer coefficient boundary conditions with the Template, Convection option and the heat transfer coefficient provided, 0.01 w/oC-cm2. Name the set contact and apply the boundary condition to the surface on the bottom of the mounting boss.

Apply contact heat transfer

◆ Loads/BCs Create/Convection/Element Uniform Option:

Template, Convection

New Set Name

contact

Target Element Type

3D

Input Data... In the Input Data form provide the heat transfer coefficient and fluid node. Leave the Template ID field blank. Convection Coefficient

0.01

Fluid Node ID



OK Select Application Region... In the Select Applications Region form select the bottom face of the mounting boss. When selecting the surface the surface chosen will be highlighted. If the incorrect surface is selected simply reselect closer to the centroidal location of the bottom mounting boss surface. The centroid is located between the mounting holes and centered on the width of the surface.

◆Geometry Select Solid Faces



Add OK Apply MSC.Patran 312 Exercise Workbook - Release 2001

5-13

Prepare and run analysis

With boundary conditions applied the model should appear as shown below.

10. Prepare and submit the model for analysis.

Prepare and run analysis

Reset the model to an isometric_view. Select Viewing from the Menu Bar to change to a isometric_view of the model. Alternately, this step can be completed using the Tool Bar Iso 1 View icon. Viewing Named View Options... Select Named View

isometric_view

Close Reset the graphics using the Reset Graphics icon.

Reduce node size using the Node Size icon.

5-14

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 5

Thermal Analysis using Imported Geometry

Select the Analysis Applications radio button to prepare the analysis. There are five parameter forms. Change the Translation Parameters... as shown below. The analysis will be submitted by selecting Apply in the Analysis form.

◆ Analysis Analyze/Full Model/Full Run Translation Parameters... File to Extract Undefined Materials:

4, mpidcgs.bin (CGS Units)

OK Solution Parameters...

◆ Celsius

Calculation Temperature Scale

OK Output Requests... Units Scale for Output Temperatures

◆ Celsius

OK Apply 11. Read results file and plot results. From within MSC.Patran the only indication that the analysis has successfully finished is the existence of an nrX.nrf.01 results file in a subdirectory one level below your working directory.

Read and plot results

Recall that p3 was initiated from a working directory which contained the exercise_05.db database file. The analysis, initiated from within MSC.Patran, created a new subdirectory with the same name as the Job Name; it should be named exercise_05/. By using Read Result in the Analysis form and Selecting Results File... you can filter down to the Job Name subdirectory and check for the existence of the results file.

◆ Analysis Read Results/Result Entities Select Results File... Directories

/exercise_05

Filter

MSC.Patran 312 Exercise Workbook - Release 2001

5-15

Quit MSC.Patran

Available Files

nr0.nrf.01

OK Select Rslt Template File... Files

pthermal_1_nodal.res_tmpl

OK Apply To plot the results to posted FEM use the Results Application radio button.

◆ Results Create/Quick Plot Select Result Cases

TIME: 0.0000000000D+00 S...

Select Fringe Result

Temperature,

Select the Fringe Attributes icon.

Display:

Element Edges

Label Style... Label Format:

Fixed

Significant figures

4

OK Apply The model should now appear as shown on the front panel of this exercise. What is the maximum reported temperature on the mounting boss? Is it at or below the required maximum of 50oC? Do the spring tab knee and mounting boss transition temperatures meet the requirement of 150oC?

Quit MSC.Patr

5-16

12. Quit MSC.Patran To stop MSC.Patran select File on the Menu Bar and select Quit from the drop-down menu.

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 6

Comparison of Two Heat Sink Designs

Objective: ■

Model two competing finned heat sinks.

■

These will be 2D axisymmetric slices.

MSC.Patran 312 Exercise Workbook - Release 2001

6-1

6-2

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 6

Comparison of Two Heat Sink Designs

Model Description: In this exercise you will model a section of a finned heatsink in order to compare the effect of using different materials. The model is a representative fin section of a compressor cylinder casing. The maximum total heating on the casing interior has been determined. A choice of materials is open; the casing can be either aluminum or 1020 steel. Other than cost the only remaining discriminator is temperature; the interior casing surface must not exceed 212oF. If both materials keep this surface at or below 212oF steel will be used otherwise aluminum would be the material of choice. This analysis will determine the material choice.

Figure 1: Slice Through Compressor Cylinder Casing Materials: Aluminum: MID = 1 1020 Steel MID = 353 R = 2.00 in.

Model this section to simplify boundary conditions

Tambient = 80oF

1.0 in.

3.0 in. 0.30 in. 0.30 in.

q/A = 3,400 Btu/hr-ft2

h =2.0 Btu/hr-ft2

MSC.Patran 312 Exercise Workbook - Release 2001

6-3

Open a new database

Exercise Overview: ■

Create a new database named exercise_06.db. Set Tolerance to Default, and the Analysis Code to MSC/THERMAL.

■

Create the five surfaces which define the heat sink geometry.

■

Transform the geometry to create the second heat sink.

■

Mesh the surfaces with an IsoMesh.

■

Create an ambient node 999.

■

Equivalence the nodes at the mating surface edges.

■

Apply element properties to the elements using the MID’s provided. These are 2D Thermal Axisymmetric elements.

■

Apply temperature, flux and convection boundary conditions.

■

Prepare and submit the model for analysis specifying that it is an Axisymmetric Geometry model, that a units conversion is required, and that the direct solver will be used for analysis.

■

Read the results file and plot results.

■

Check the results against the requirement of 212oF.

■

Quit MSC.Patran.

Exercise Procedure: Open a new database

1.

Open a new database named exercise_06.db.

Within your window environment change directories to a convenient working directory. Run MSC.Patran by typing p3 in your xterm window. Next, select File from the Top Menu Bar and select New … from the dropdown menu. Assign the name exercise_06.db to the new database by clicking in the New Database Name box and entering exercise_06. Select OK to create the new database. File New ... New Database Name

exercise_06

OK 6-4

MSC.Patran 312 Exercise Workbook - Release 2001

Comparison of Two Heat Sink Designs

WORKSHOP 6

MSC.Patran will open a Viewport and change various Main Form selections from a ghosted appearance to a bold format. When the New Model Preferences form appears on your screen, set the Tolerance to Default, and the Analysis Code to MSC/THERMAL. Select OK to close the New Model Preferences form. Tolerance

◆ Default

Analysis Code

MSC/THERMAL

OK 2.

Create the five surfaces which define the model geometry.

Select the Geometry Applications radio button. Create a surface using the following Action, Object, and Method. Click in the appropriate list boxes to edit the default values and change them to values listed below.

Create the heat sink surfaces

◆ Geometry Create/Surface/XYZ Vector Coordinate List



Origin Coordinates List

[2 0 0]

Apply Surface 1 will appear in the viewport. As shown below

MSC.Patran 312 Exercise Workbook - Release 2001

6-5

Create the heat sink surfaces

Remaining in the Geometry form change the Action, Object, and Method to Transform the existing surface into the required geometry. The Translation Vector entries are easily determined from Figure 1 and are included in the form entries below.

◆ Geometry Transform/Surface/Translate Translation Vector



Auto Execute Surface List



Apply Use Show Label icon to display labels.

Complete the fin by transforming the newly created Surface 2. Note that the Repeat Count is adjusted to 3 to create the full fin length.

◆ Geometry Transform/Surface/Translate Translation Vector



Repeat Count

3

Surface List



Apply

6-6

MSC.Patran 312 Exercise Workbook - Release 2001

Comparison of Two Heat Sink Designs

WORKSHOP 6

The resulting model is shown below.

5

6 2

7 3

2

3

9 4

8

11 5

10

12

1 1

4 Y Z

3.

X

Transform the geometry to create the second heat sink.

Duplicate the entire heat sink cross section by transforming all the existing surfaces. Note that the Repeat Count is adjusted back to 1 to create the a single copy of the heat sink. The completed geometry is shown below.

Create the second heat sink

◆ Geometry Transform/Surface/Translate Translation Vector



Repeat Count

1

Surface List



Apply

MSC.Patran 312 Exercise Workbook - Release 2001

6-7

IsoMesh the surfaces

The display should now appear as shown below.

17

18 7

14

15

6

13

1

6 2

4.

IsoMesh the surfaces

3

1

9

20

21 22

10

23 24

3

7

4

8

9 10

5

11 12

4

Y Z

19

16

5 2

8

X

Mesh the surfaces with an IsoMesh.

Select the Finite Elements Applications radio button. Set the Action, Object, and Type to Create/Mesh/Surface. Accept the Global Edge Length of 0.1 and select all surfaces for inclusion in the Surface List.

◆ Finite Elements Create/Mesh/Surface Surface List



Apply Use Hide Label Icons to turn off all labels.

6-8

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 6

Comparison of Two Heat Sink Designs

The display should now appear as shown below.

Y Z

5.

X

Create an ambient node 999.

Using the Finite Elements form create a boundary node which is not associated with geometry. The node is numbered 999. Locate the node at [6.2 0.9 0] to the right of and between the two models.

Create an ambient node

◆ Finite Elements Create/Node/Edit Node ID List

999

Associate with Geometry Node Location List

[6.2 0.9 0]

Apply MSC.Patran 312 Exercise Workbook - Release 2001

6-9

Equivalence nodes

Increase the display size of nodes to facilitate the application of boundary condition. Use either Display/Finite Elements... or the associated Tool Bar Node Size icon to change the node size. The model should now appear as shown below. Display Finite Elements... 6

Node Size

Apply Cancel

Y Z

Equivalen ce nodes

6.

X

Equivalence the nodes at the mating surface edges.

Using the Finite Elements form set the Action/Object/Method to Equivalence/All/Tolerance Cube and select Apply to eliminate duplicate nodes created at geometric entity edges.

◆ Finite Elements Equivalence/All/Tolerance Cube Apply 7.

Apply element properties

6-10

Apply element properties to the elements using the two material properties MID’s, 1 and 353.

MSC.Patran 312 Exercise Workbook - Release 2001

Comparison of Two Heat Sink Designs

WORKSHOP 6

In a typical modelling sequence the Materials Application radio button would be the next stop to define a material for application in Element Properties. However, MSC.Thermal includes a Material Properties Database which contains 970 materials with thermal properties already defined. Use this database to facilitate the analysis. Select the PropertiesApplications radio button. Set the Action, Dimension, and Method to Create/2D/Thermal Axisymmetric. Enter Property Set Name Steel. Select the Input Properties... box. In the Input Properties form, click in the Material Name box and enter 353. Select OK to close the form.Click in the Select Members box and drag a rectangle around the lower model in the viewport. Select Add then Apply in the Element Properties form to complete the element property definition.

◆ Properties Create/2D/ Thermal Axisymmetric Steel

Property Set Name

Input Properties... 353

Material Name

OK

Select Members

Add Apply Perform the same steps for upper model using, Aluminum, for the Property Set Name, and 1 for the Material Name. 8.

Apply the temperature, convection, and flux boundary conditions to the model.

Begin applying boundary conditions. Select the Loads/BCs Applications radio button. Create a fixed 80.0oF nodal boundary named Ambient In the Input Data form define the fixed temperature. In the Select Applications Region form pick node 999.

Apply boundary conditions

◆ Loads/BCs Create/Temperature/Nodal Option:

Fixed MSC.Patran 312 Exercise Workbook - Release 2001

6-11

Apply boundary conditions

New Set Name

Ambient

Input Data... Fixed Temperature

80.0

OK Select Application Region... Geometry Filter

◆ FEM

Select Nodes



Add OK Apply Create the heat transfer coefficient boundary conditions with the Template, Convection option, set name Air, and a heat transfer coefficient of 2.0 Btu/ oF-hr-ft2. Apply the boundary condition to the exposed edges of both finned heat sinks as shown in Figure1. The same boundary condition is applied to both heat sink models.

◆ Loads/BCs Create/Convection/Element Uniform Option:

Template, Convection

New Set Name

Air

Target Element Type

2D

Input Data... In the Input Data form provide the heat transfer coefficient and fluid node. Convection Coefficient

2.0

Fluid Node ID



OK Select Application Region...

6-12

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 6

Comparison of Two Heat Sink Designs

In the Select Applications Region form select the right facing and bottom facing exposed edges of the finned heat sinks. Switch to the Select an Edge icon in the Select Menu form. When selecting the edges the edge chosen will be highlighted. Hold down the key and use the left mouse button to collect all the edges in the Select Surfaces or Edges box. Geometry Filter

◆Geometry

Select Menu

Select an Edge icon

Select Surfaces or Edges



Add OK Apply Create a set name Flux of 3400 Btu/hr-ft2. Apply the boundary condition to the left facing edges of both finned heat sinks as shown in Figure1. The same boundary condition is applied to both heat sink models.

◆ Loads/BCs Create/Heating/Element Uniform Option:

Flux, Fixed

New Set Name

Flux

Target Element Type

2D

Input Data... 3400

Heat Flux

OK In the Select Applications Region form select the left facing exposed edges of the finned heat sinks. Switch to the Select an Edge icon, if necessary, in the Select Menu form. When selecting the edges the edge chosen will be highlighted. Hold down the key and use the left mouse button to collect all the edges in the Select Surfaces or Edges box. Select Application Region... MSC.Patran 312 Exercise Workbook - Release 2001

6-13

Prepare and run analysis

Geometry Filter

◆Geometry

Select Menu

Select an Edge icon

Select Surfaces or Edges



Add OK Apply With boundary conditions applied the model should appear as shown below

3400.

2.000

3400.

2.000

2.000

3400.

2.000 2.000

80.00 2.000

2.000

2.000

3400.

999 2.000

3400.

2.000

2.000

3400.

2.000 2.000

2.000

2.000

2.000

Y Z

9.

Prepare and run analysis

X

Prepare and submit the model for analysis.

Select the Analysis Applications radio button to prepare the analysis. Select the parameter forms reviewing and changing the settings as shown below. The analysis is submitted by selecting Apply in the Analysis form.

◆ Analysis 6-14

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 6

Comparison of Two Heat Sink Designs

Analyze/Full Model/Full Run Translation Parameters... Model Dimensionality

◆ Axisymmetric Geometry, R Z Co-ordinates

Radial, R Co-ordinate

◆ X axis ◆ Y axis

Centerline, Z Co-ordinate Perform Geometry Units Conversion From Units

inches

To Units

feet

File to Extract Undefined Materials:

3,mpidfph.bin (Btu-feet-lbm..

OK Solution Parameters... Calculation Temperature Scale

◆ Fahrenheit

Solver Option

2, Direct Solver

Run Control Parameters... Initial Temperature

212.0

Initial Temperature Scale

◆ Fahrenheit

OK OK Output Requests... Units Scale for Output Temperatures

◆ Fahrenheit

Units Definition for Time Label

Hours

OK Submit Options... OK Apply

MSC.Patran 312 Exercise Workbook - Release 2001

6-15

Read and plot results

While waiting for the analysis to finish. Reset Graphics and reduce node size.

Read and plot results

10. Read results file and plot results. From within MSC.Patran the only indication that the analysis has successfully finished is the existence of an nrX.nrf.01 results file in a subdirectory one level below your working directory. P3 was initiated from a working directory which contained the exercise_06.db database. The analysis created a new subdirectory with the same name as the Job Name; exercise_06/. By using Read Result in the Analysis form and Selecting Results File... you can filter down to the Job Name subdirectory and check for the existence of a results file.

◆ Analysis Read Results/Result Entities Select Results File... Directories

/exercise_06

Filter Available Files

nr0.nrf.01

OK Select Rslt Template File... Files

pthermal_1_nodal.res_tmpl

OK Apply To plot the results to posted FEM use the Results Application radio button.

◆ Results Create/Quick Plot

6-16

Select Result Cases

TIME: 0.0000000000D+00 S...

Select Fringe Result

Temperature,

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 6

Comparison of Two Heat Sink Designs

Select the Fringe Attributes icon.

Display:

Element Edges

Label Style... Label Format:

Fixed

Significant figures

4

OK Apply The model should now appear as shown on the front panel of this exercise. Which material will be chosen for the cylinder casing? 11. Quit MSC.Patran To stop MSC.Patran select File on the Top Menu Bar and select Quit from the drop-down menu.

MSC.Patran 312 Exercise Workbook - Release 2001

Quit MSC.Patr

6-17

Quit MSC.Patran

6-18

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 7

An Oven Window Design

Objective: ■

Model a 2D planar slice of an oven window.

■

Learn how to initiate and use Utilities.

MSC.Patran 312 Exercise Workbook - Release 2001

7-1

7-2

MSC.Patran 312 Exercise Workbook - Release 2001

An Oven Window Design

WORKSHOP 7

Model Description: In this exercise you will model a 2D planar section of an oven window. You will learn how to initiate and use Utilities which facilitate this task. A manufacturer of appliances is proposing a self cleaning oven design that uses a composite window separating the oven cavity from room air. The composite consists of two high temperature plastics (A & B) whose physical and thermal attributes are shown below. The combined convection/ linearized radiation heat transfer parameters for inside and outside of the oven are also shown. (Note: Radiation will be linearized and is include in the heat transfer coefficient). The design specification for safe operation requires an outside oven temperature of 50ΟC or less. The following assumptions can be made for the model: ■

Steady-state conditions exist.

■

The oven door can be modeled as a 2-dimensional slice.

■

Contact resistance is negligible.

■

Each plastic is homogeneous with constant properties.

Figure 1

Oven Cavity Toven = 345o C hoven = 16 W/m2C

A

B

Composite Window 0.2 m Air

LB Air

Trequired ≤ 50οC

LA kA = 0.13 W/mC

Ambient

kB = 0.07 W/mC

o

T∞ = 24 C hambient = 13 W/m2C

LA = 0.050 m LB = 0.030 m MSC.Patran 312 Exercise Workbook - Release 2001

7-3

Information on Utilities: Utilities refer to a set of tools which facilitate the use of MSC.Patran. These tools are supplied with MSC.Patran. In version 9.0 they are located on each CD ROM. Utilities are written or supplied by MSC.Software software developers, applications engineers, and anyone within MSC who has a good idea for improving MSC.Patran functionality. Sometimes Utilities are the vehicle for implementing an improvement which for organizational reasons will not be officially implemented within a reasonable release horizon. Utilities are written in PCL, MSC.Patran Command Language. Since Utilities are developed from the personal initiative of individuals and not as part of the MSC.Software corporate software development strategy, they are not subjected to any formal quality assurance testing. Hence, they are supplied by MSC.Software as a courtesy but they are officially not supported by MSC.Software. Most Utilities are supplied with the authors name, an e-mail address, and telephone number. If you have a problem with a Utilities tool you may contact the author if ownership data is available. You may report suspected or identified problems with Utilities to the MSC.Patran support line but no obligation to fix the Utilities problem is incurred by MSC.Software. That being said, Utilities are generally reliable and quite handy. Most intermediate and advanced user of MSC/PATRAN install and use Utilities. Load the MSC.Patran CD in the CD-ROM drive and mount the CD-ROM drive Installation instructions are listed in “Installing PCL Utilities and MSC.Software Institute Files on Unix”, p. 43 of “MSC.Patran Installation and Operations Guide”. Instructions for Windows NT are found on p. 65. If the user has installed MSC.Patran with the “FULL” install option utilities are loaded automatically. If user selects “CUSTOM” installation, then PCL Utilities must be selected as an option under the MSC.Patran Core Applications. When loaded (installed) Utilities are initiated by copying the p3epilog.pcl file from /shareware/msc/unsupported/utilities (e.g., /patran/patran3/shareware/msc/unsupported/utilities/p3epilog.pcl), into a users home directory (for user-by-user access) or the P3_HOME directory (for a system wide access). Once the p3epilog.pcl file is in place Utilities is available as a pick on the Menu Bar after re-starting MSC.Patran.

7-4

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 7

An Oven Window Design

Exercise Overview: ■

Create a new database named exercise_07.db. Set Approximate Maximum Model Dimension to 0.20, and the Analysis Code to MSC/THERMAL.

■

Create two surfaces which define the oven window geometry.

■

Mesh the surfaces with an IsoMesh, Global Edge Length of 0.003.

■

Create two fluid nodes 9998 and 9999 for the oven interior and ambient conditions respectively.

■

Equivalence the nodes at the mating surface edges.

■

Define the two material properties for the plastics.

■

Apply element properties to the elements using the defined materials. These are Thermal 2D elements.

■

Use the Fields Form to define the temperature distribution at the interior pane upper edge.

■

Apply temperature and convection boundary conditions.

■

Visualize and verify the convection LBC’s using Utilities/ Thermal/Thermal BC Display...

■

Prepare and submit the model for analysis specifying that it is a 2D Plane Geometry model and that the Weakly Nonlinear Solution solver will be used for analysis.

■

Read the results file and plot results.

■

Check the results against the requirement of 50oC.

■

Quit MSC.Patran.

MSC.Patran 312 Exercise Workbook - Release 2001

7-5

Open a new database

Exercise Procedure: Open a new database

1.

Open a new database named exercise_07.db.

Within your window environment change directories to a convenient working directory. Run MSC.Patran by typing p3 in your xterm window. Next, select File from the Menu Bar and select New … from the drop-down menu. Assign the name exercise_07.db to the new database by clicking in the New Database Name box and entering exercise_07. Select OK to create the new database. File New ... exercise_07

New Database Name

OK MSC.Patran will open a Viewport and change various Main Form selections from a ghosted appearance to a bold format. When the New Model Preferences form appears on your screen, set the Approximate Maximum Model Dimension to 0.20, and the Analysis Code to MSC/THERMAL. Select OK to close the New Model Preferences form. Approximate Maximum Model Dimension: Analysis Code

0.20 MSC/THERMAL

OK 2.

Create the oven window

Create two surfaces which define the oven window geometry.

Select the Geometry Applications radio button. Create a surface using the following Action, Object, and Method. Click in the appropriate list boxes to edit the default values and change them to values listed below.

◆ Geometry Create/Surface/XYZ Vector Coordinate List



Apply

7-6

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 7

An Oven Window Design

Turn on labels using the Show Labels icon.

Create the second surface from the same Action/Object/Method but change the Vector Coordinate List to . Modify the Origin Coordinates List by clicking in the list box and selecting Point 4 from the viewport.

◆ Geometry Create/Surface/XYZ Auto Execute Vector Coordinate List



Origin Coordinates List



Apply The model will appear as shown below.

MSC.Patran 312 Exercise Workbook - Release 2001

7-7

IsoMesh the surfaces

3.

IsoMesh the surfaces

Mesh surfaces with an IsoMesh, global edge length of 0.003.

Select the Finite Elements Applications radio button. Set the Action, Object, and Type to Create/Mesh/Surface. Change the Global Edge Length to 0.003 and select both surfaces for inclusion in the Surface List.

◆ Finite Elements Create/Mesh/Surface Global Edge Length

0.003

Surface List



Apply Turn off labels using Hide Labels icon.

Create an ambient node

4.

Create two fluid nodes 9998 and 9999 for the oven interior and ambient conditions respectively.

Using the Finite Elements form create a boundary nodes which are not associated with geometry. The node numbers are 9998 and 9999. Locate the nodes at [-0.03 0 0] and [0.11 0 0], to the left and right of model. The spatial location of the boundary nodes is irrelevant to the analysis; but, these locations facilitate display and verification of LBC’s.

◆ Finite Elements Create/Node/Edit Node ID List

9998

Associate with Geometry Node Location List

[ -0.03 0 0]

Apply Node Location List

[0.11 0 0]

Apply

7-8

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 7

An Oven Window Design

Increase the display size of nodes to facilitate the application of boundary condition. Use either Display/Finite Elements or the associated Toolbar Node Size icon to change the node size. The model should now appear as shown below. Display Finite Elements... Node Size

6

Apply Cancel or,

The display should now appear as shown below.

MSC.Patran 312 Exercise Workbook - Release 2001

7-9

Equivalence nodes

5.

Equivalence the nodes at the mating surface edges.

Using the Finite Elements form set the Action, Object, and Method to Equivalence/All/Tolerance Cube and select Apply to eliminate duplicate nodes created at geometric entity edges.

Equivalen ce nodes

◆ Finite Elements Equivalence/All/Tolerance Cube Apply 6.

Define the two material properties for the plastics.

Since this will be a steady state analysis, thermal conductivity is the only material property used in the solution. Thermal conductivity values are provided in Figure 1; however, the Input Options form also requires data for Density and Specific Heat. Enter a value of 1.0 in each of these fields. The Apply button is selected from within the Input Options form. The form does not close upon hitting Apply. This is a convenient, if unintended, feature since one needs only to enter a new material name in Material Name and proceed with entering new material data in the Input Options form. After each Apply the new material should appear in the Existing Materials list box on the Materials form.

◆ Materials Create/Isotropic/Manual Input Material Name

ka

Input Properties... Thermal Conductivity =

0.130

Density =

1.0

Specific Heat =

1.0

OK Apply

7-10

Material Name

kb

Thermal Conductivity =

0.07

Density =

1.0

Specific Heat =

1.0

MSC.Patran 312 Exercise Workbook - Release 2001

Define two materials

An Oven Window Design

WORKSHOP 7

OK Apply 7.

Apply element properties to the elements using the defined materials. These are Thermal 2D elements.

Apply element properties

Select the Properties Applications radio button. Set the Action, Dimension, and Type to Create/2D/Thermal 2D. Enter Property Set Name interior_pane. Select the Input Properties... box. Click in the Material Name box and select ka from the Material Property Sets list box. Select OK to close the form.Click in the Select Members box and choose Surface 1 from the default viewport. Select Add then Apply in the Element Properties form to complete the element property definition.

◆ Properties Create/2D/Thermal 2D Property Set Name

interior_pane

Input Properties... Material Name



OK Select Members



Add Apply Perform the same steps for Surface 2 using, exterior_pane, for the Property Set Name, and select kb for the Material Name from the Material Property Sets list box.

◆ Properties Create/2D/Thermal 2D Property Set Name

exterior_pane

Input Properties... Material Name



OK Select Members



Add MSC.Patran 312 Exercise Workbook - Release 2001

7-11

Create a spatial field

Apply 8.

Define the temperature distribution at the interior pane upper edge.

Select the Fields Applications radio button. Set the Action, Object, and Method to Create/Spatial/Tabular Input. Enter Field Name edge_T. Select Input Data... and enter 2 data pairs 0.0, 345.0 and 0.05, 38.0 via the Input Scalar Data box. Select OK and Apply to finish the definition.

Create a spatial field

◆ Fields Create/Spatial/Tabular Input edge_T

Field Name:

Input Data... Data:



Input Scalar Data:

0.0

Input Scalar Data:

0.05

Data:



Input Scalar Data:

345.0

Input Scalar Data:

38.0

OK Apply

9.

Apply temperature and conditions.

convection

boundary

Begin applying boundary conditions. Select the Loads/BCs Applications radio button. Create a fixed 345oC nodal boundary temperature named oven. In the Input Data form define the fixed temperature. In the Select Applications Region form pick node 9998 located to the left of the window.

◆ Loads/BCs Create/Temperature/Nodal

7-12

Option:

Fixed

New Set Name

oven

MSC.Patran 312 Exercise Workbook - Release 2001

Apply boundary conditions

WORKSHOP 7

An Oven Window Design

Input Data... 345.0

Fixed Temperature

OK Select Application Region... Geometry Filter

◆ FEM

Select Nodes



Add OK Apply Repeat the steps for a fixed 24oC boundary temperature named ambient. In the Select Applications Region form pick node 9999 located to the right of the oven window. ambient

New Set Name

Input Data... 24.0

Fixed Temperature

OK Select Application Region... Select Nodes



Add OK Apply Repeat steps for fixed edge temperature distribution using spatial field edge_T. Apply the distribution to the upper Geometry edge of the interior pane. New Set Name

edge

Input Data... Select Spatial Field... Fixed Temperature

MSC.Patran 312 Exercise Workbook - Release 2001

7-13

Apply boundary conditions

Close OK Select Application Region... Geometry Filter

◆ Geometry

Select Menu

curve or edge icon

Select Geometric Entities



Add OK Apply Create the heat transfer coefficient boundary conditions with the Template, Convection option, set name oven_convection, and a heat transfer coefficient of 16.0 W/oC-m2. Apply the boundary condition to the left most oven window surface(edge) as shown in Figure1 with fluid node 9998.

◆ Loads/BCs Create/Convection/Element Uniform Option:

Template, Convection

New Set Name

oven_convection

Target Element Type

2D

Input Data... In the Input Data form provide the heat transfer coefficient and fluid node. Convection Coefficient

16.0

Fluid Node ID



OK Select Application Region...

7-14

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 7

An Oven Window Design

In the Select Applications Region form select the left facing surface (edge) of the oven window. Switch to the Select an Edge icon in the Select Menu form. When selecting the edges the edge chosen will be highlighted. Geometry Filter

◆Geometry

Select Menu

Edge icon

Select Surfaces or Edges



Add OK Apply

Repeat these steps for a New Set Name air_convection with a heat transfer coefficient of 13.0 W/oC-m2 applied to the right most oven window surface(edge) as shown in Figure 1 with fluid node 9999. New Set Name

air_convection

Target Element Type

2D

Input Data... Convection Coefficient

13.0

Fluid Node ID



OK Select Application Region... Select Surfaces or Edges



Add OK Apply

MSC.Patran 312 Exercise Workbook - Release 2001

7-15

Use Shareware to verify LBC’s

With boundary conditions applied the model should appear as shown below.

Use Shareware to verify LBC’s

10. Visualize and verify the convection LBC’s using Utilities/ Thermal Tools/Thermal BC Display... Shareware contains various utilities for facilitating model creation and LBC’s verification. Verify your convective coupling by drawing a vector from the centroid of each element to the associated fluid node using Utilities/ Thermal/Thermal BC Display... Utilities Thermal Thermal BC Display... OK Apply

7-16

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 7

An Oven Window Design

The model should appear as shown below.

Use Clear and Close in the Thermal BC’s form to revert to a normal display. Clear Close Reduce the node size using the Node Size icon.

11. Prepare and submit the model for analysis. Select the Analysis Applications radio button to prepare the analysis. Select the parameter forms reviewing and changing the settings as shown below. The analysis is submitted by selecting Apply in the Analysis form.

Prepare and run analysis

◆ Analysis Analyze/Full Model/Full Run MSC.Patran 312 Exercise Workbook - Release 2001

7-17

Read and plot results

Translation Parameters... Model Dimensionality

◆ 2D Plane Geometry, XY Co-ordinates (unit Thickness in Z)

OK Solution Parameters... Calculation Temperature Scale

◆ Celsius

Solver Option

1, Weakly Nonlinear Solution

OK Output Requests... Units Scale for Output Temperatures

◆ Celsius

OK Apply

Read and plot results

12. Read results file and plot results. From within MSC.Patran the only indication that the analysis has successfully finished is the existence of an nrX.nrf.01 results file in a subdirectory one level below your working directory. P3 was initiated from a working directory which contained the exercise_07.db database. Applying the analysis created a new subdirectory with the same name as the Job Name; exercise_07/. By using Read Result in the Analysis form and Selecting Results File... you can filter down to the Job Name subdirectory and check for the existence of a results file.

◆ Analysis Read Results/Result Entities Select Results File... Directories

/exercise_07

Filter Available Files

nr0.nrf.01

OK Select Rslt Template File... Files

7-18

pthermal_1_nodal.res_tmpl

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 7

An Oven Window Design

OK Apply To plot the results to posted FEM use the Results Application radio button.

◆ Results Create/Quick Plot Select Result Case

TIME: 0.0000000000D+00 S...

Select Fringe Results

Temperature,

Select the Fringe Attributes icon.

Display:

Element Edges

Label Style... Label Format:

Fixed

Significant figures

4

OK Apply The model should now appear as shown on the front panel of this exercise. What is the exterior temperature of the oven window? Is it at or below the required maximum of 50oC?

13. Quit MSC.Patran To stop MSC.Patran select File on the Menu Bar and select Quit from the drop-down menu.

MSC.Patran 312 Exercise Workbook - Release 2001

Quit MSC.Patr

7-19

Quit MSC.Patran

7-20

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 8

Temperature Dependent Material Properties

Objective: ■

You will create a 2D material slice consisting of two materials with temperature dependent material properties.

■

You will visually and qualitatively compare the MSC/ THERMAL results with the results of an analytical solution.

MSC.Patran 312 Exercise Workbook - Release 2001

8-1

8-2

MSC.Patran 312 Exercise Workbook - Release 2001

Temperature Dependent Material Properties

WORKSHOP 8

Model Description: In this exercise you will learn to create temperature dependent material properties. There are very few analytical solutions available for composite materials with temperature dependent conductivities. Recently, K. C. Chang and V. J. Payne published an analytic solution for the problem you will analyze in this exercise (Journal of Heat Transfer, Feb. 1991, Vol. 113, pp. 237). Results of their work have been included at the end of this exercise to allow you to qualitatively compare your solution to theirs.

Material 1

Material 2 T = 100OC = 373.2 K

T = 600OC = 873.2 K

Ta = 0O C = 273.2 K

0.5 X 0.5 Dimension K1= K10 (1 + α1 Τ) K2 = K20 (1 +α2 Τ)

.

K10 = 0.060

α1 = 0.0006

K20 = 0.001

α2 = 0.00001

MSC.Patran 312 Exercise Workbook - Release 2001

8-3

Create a new database

Exercise Overview: ■

Create a new database named exercise_08.db. Set the Tolerance to Default, and the Analysis Code to MSC/THERMAL.

■

Create two surfaces which model the two adjoining material slabs.

■

Mesh the surfaces with an IsoMesh.

■

Identify “cracks” in the model and Equivalence the nodes at the mating surface edges.

■

Define the two materials using Fields/Create/ Material Property/General.

■

Using the fields just defined create Material 1 and Material 2.

■

Apply element properties to the elements referencing the two material properties just defined.

■

Apply the three temperature boundary conditions to the edges of your model.

■

Prioritize temperature boundary conditions at the lower corners.

■

Prepare and submit the model for analysis.

■

Read results file and plot results.

■

Compare the results to the analytical solution.

■

Quit MSC.Patran.

Exercise Procedure: Create a new database

1.

Create a new database named exercise_08.db. Set the Tolerance to Default, and the Analysis Code to MSC/THERMAL.

Within your window environment change directories to a convenient working directory. Run MSC.Patran by typing p3 in your xterm window. Next, select File from the Menu Bar Menu Bar and select New… from the drop-down menu.

8-4

MSC.Patran 312 Exercise Workbook - Release 2001

Temperature Dependent Material Properties

WORKSHOP 8

Assign the name exercise_08.db to the new database by clicking in the New Database Name box and entering exercise_08 (.db will automatically be appended). Select OK to create the new database. MSC.Patran will open a Viewport and change various Main Form selections from a ghosted appearance to a bold format. When the New Model Preferences form appears on your screen, set the Tolerance to Default, and the Analysis Code to MSC/THERMAL. Select OK to close the New Model Preferences form. 2.

Create two surfaces which model the two adjoining material slabs.

Select the Geometry Applications radio button. Set the Action, Object, and Method to Create/Surface/XYZ. Change the Vector Coordinates List to and click on the Apply button to create the first patch

Create the two material

Change the Origin Coordinates List to [0.5, 0, 0], and click on the Apply button to create the second surface.

Y Z

X

MSC.Patran 312 Exercise Workbook - Release 2001

8-5

IsoMesh both surfaces

3.

IsoMesh both surfaces

Mesh the surfaces with an IsoMesh.

Select the Finite Elements Applications radio button. Set the Action, Object, and Type to Create/Mesh/Surface. Set the Global Edge Length to 0.025. Click in the Surface List box and drag a rectangle around both surfaces. Select Apply to complete the meshing function. The completed form and resulting display are shown below. Finite Elements Action: Object:

Type:

Create Mesh Surface

Output IDs Node ID List 1 Element ID List 1 Global Edge Length 0.025 Element Topology Quad4 Quad5 Quad8 Mesher

◆Paver ◆IsoMesh◆ IsoMesh Parameters... Y

Node Coordinate Frames... Z

Surface List Surface 1 2

X

-Apply-

The display should appear as shown above. If it does not, select the undo icon and analyze the error to a resolution.

Equivalen ce mesh nodes

4.

Identify “cracks” in the model and equivalence the nodes at the mating surface edges.

In the Finite Elements form set the Action, Object, and Test to Verify/Element/Boundaries. Select Apply. In the Finite Elements form set the Action, Object, and Method to Equivalence/All/Tolerance Cube. Select Apply to complete the function. Verify element boundaries again. 8-6

MSC.Patran 312 Exercise Workbook - Release 2001

Temperature Dependent Material Properties

WORKSHOP 8

The nodes bounding the interior edges will be circled in the display and the Command Window will indicate that a number of nodes are deleted. All gaps or cracks have now been eliminated from the mesh. 5.

Define the two materials using Fields/Create/ Material Property/General.

Select the Fields Applications radio button. Set the Action, Object, and Method to Create/Material Property/ General.

Define the material property fields

Enter a Field Name K2 and select Input Data... In the General Field Input Data form Select Function Term mpid_arbt_plyn. General Field Input Data Select Function Term: Function Term Type:

P3 Functions

Term Sub-Type: MSC/THERMAL Matl Func Select Function Term: mpid_arbt_plyn mpid_bghm mpid_cnst

Function Expression

Modify Highlighted Function OK

An Arbitrary Order Polynomial form will be displayed. On this form, change the Temperature Units option menu to Kelvin. Then enter Coefficient Data for Material K2 conductivity, (K2 = 0.001 + 0.00000001 T). First enter 0.001 in the Coefficient,A(Index) followed by a carriage return. Next enter 1.0E-8 followed by a carriage return. Before completing this form enter a description in the Description entry box.

MSC.Patran 312 Exercise Workbook - Release 2001

8-7

Define the material property fields

The form should appear as shown below. Arbitrary Order Polynomial Define Material Property: Arbitrary Order Polynomial P(X) = A(1) + A(2)*X + ... A(n)*X**(n-1) Note: The temperature scale only indicates the valid units. ICCALC units will be used in the evaluation. Select Existing Table... Build Arbitrary Order Polynomial Table Description - Arbitrary Order Polynomial Table

Material K2 Material Property ID (MPID) 100001

Scale Factor 1.0

Independent Variable Type Temperature

Temperature Units Kelvin

Input Coefficient, A(I) Value Coefficient, A(I) 1

0.001

2

9.99999999E-09

3 4

Clear Selected cell(s) Number of Rows to Insert OK

Delete selected row (s) 1 Defaults

Insert row(s) Cancel

Select OK in the Arbitrary Order Polynomial form. Select OK in the General Field Input Data form. Select Apply button on the Fields form to complete the function. In the Field form change Field Name to K1. Again choose the mpid_arbt_plyn. Click on the Coefficient 1 cell in the Coefficient Data frame and enter the Coefficient,A(Index) data for the thermal conductivity of Material 1, (K1 = 0.06 + 0.000036T). Change the Temperature units to Kelvin and add a description in the Description entry box.

8-8

MSC.Patran 312 Exercise Workbook - Release 2001

Temperature Dependent Material Properties

WORKSHOP 8

6.

Using the fields just defined create Material 1 and Material 2.

Select the Materials Applications radio button. Set the Action, Object, and Method to Create/Isotropic/Manual Input. Enter Material_1 in the Material Name databox. Select Input Properties... In the Input Options form click into the Thermal Conductivity data box.

Define material properties

The form should be modified to include a Time, Temperature, or Constant Fields: list box. Select K1 from the listbox. Enter unit values for Density and Specific Heat. Input Options Thermal properties

Constitutive Model Property Name

Value

Thermal Conductivity

K1

Density

1.0

Specific Heat

1.0

Phase change temperature Latent Heat

Time, Temperature or Constant Fields: K1 K2

Repeat the same procedure for Material_2; this time selecting K2 for Thermal Conductivity. After creating both materials select Cancel to close the Input Options form 7.

Apply element properties to the elements selecting the two material properties just defined. Select the Properties Applications radio button. Set the Action, Dimension, and Type to Create/2D/Thermal 2D. Enter Property Set Name Prop1. Select the Input Properties... box. In the Input Properties form, click in the Material Name box and select Material_1 from the Material Properties Sets list. Select OK to close the form. Click in the Select Members box and select Surface 1, the left surface. Select Add then Apply in the Element Properties form to complete the element property definition for Surface 1. MSC.Patran 312 Exercise Workbook - Release 2001

Apply element properties

8-9

Apply boundary temperatures to 3 edges

Perform the same steps for Surface 2, the right surface, using Prop2, for the Property Set Name, and Material_2 for the Material Name. 8.

Apply boundary temperature s to 3 edges

You will now apply the three temperature boundary conditions to the edges of your model.

Left vertical edge of Surface 1: Select the Loads/BCs Applications radio button. Set the Action, Object, and Type to Create/Temperature (PThermal)/Nodal with an Option: of Fixed. Enter the name, Mat1_Edge_Temp, into the New Set Name data box. Click on the Input Data... button and enter a Fixed Temperature of 873.2. Click on the OK button to close the Input Data form. Select the Select Application Region... button and set the Geometry Filter to Geometry. Click on the Select Geometry Entities box, select the Curve or Edge icon in the Select Menu. Select the left-hand vertical edge of Surface 1. Select Add then OK to affect and close the Select Application Region form. The completed forms are shown below. Input Data

Load/Boundary Conditions Create

Action:

Object: Temperature(PThermal)

Option:

Select Spatial Field...

Fixed

Analysis Type:

Application Region

Thermal

Default...

Select Geometry Entities

Reset

Current Load Case:

Type:

Geometry Filter Geometry FEM

Fixed Temperature 873.2

Nodal

Type:

Select Application Region

OK

Static

Existing Sets

Cancel Add

Remove

Application Region Surface 1.1

New Set Name Mat1_Edge_Temp

Input Data... 8-10

MSC.Patran 312 Exercise Workbook - Release 2001

OK

WORKSHOP 8

Temperature Dependent Material Properties Select Apply to create the temperature boundary condition. Perform similar steps to assign the remaining temperature boundary conditions to your model. Use the following New Set Name, and Fixed Temperature values. New Set Name

Fixed Temp

Mat1_2_Bottom_Edge_Temp Mat2_Edge_Temp

273.2 373.2

Your model should now look like the one shown below.

Applying the temperature boundary conditions to the various edges of your model created a conflict at the two lower corner points. At the lower left corner both the 873.2 and 273.2 temperature boundary conditions were applied. At the lower right corner both the 373.2 and 273.2 temperature boundary conditions were applied. By default MSC/PATRAN adds overlapping boundary conditions. To fix the lower corner temperature to 273.2 you must tell MSC/PATRAN that the boundary condition you applied to the bottom edge of the model has priority over the conflicting vertical edge boundary conditions.

MSC.Patran 312 Exercise Workbook - Release 2001

8-11

Prioritize temperature BC’s

Prioritize temperatur e BC’s

9.

Prioritize temperature boundary conditions at the lower corners.

Select the Load Cases Applications radio button.Change the Action: to Modify. In the Load Cases form highlight the Default load case in the Existing Load Cases list box, if necessary. Select the Priority cell for LBC 1, Mat1_2_Bottom_Edge_Temp. Select the Value button. A value of 1 should appear in the Priority cell. Select the Mat1_Edge_Temp LBC then again set the Priority to 2 using the Value cell. Repeat for the last LBC, Mat2_Edge_Temp. The completed forms are shown below.

Select OK in the Prioritize Load/BCs form and Apply in the form. If the Message box, “Do you wish to overwrite?” appears, answer Yes.

Load Cases

8-12

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 8

Temperature Dependent Material Properties

10. Prepare and submit the model for analysis. Select the Analysis Applications radio button to prepare the analysis. Select Translation Parameters... Select the 2D Plane Geometry,XY Co-ordinates (Unit Thickness in Z) radio button in Model Dimensionality. Select OK to close the P/ Thermal Translation Parameters form.

Prepare and run analysis

Select Solution Parameters... Select the Kelvin radio button in Calculation Temperature Scale. Select OK to close the P/Thermal Solution Parameters form. Select Output Requests... Select the Celsius radio button in Unit Scale for Output Temperatures. Select OK to close the P/Thermal Output Requests form. Since all other defaults are acceptable submit the analysis by selecting Apply in the Analysis form From within MSC.Patran the only indication that the analysis has successfully finished is the existence of an nrX.nrf.01 results file in a subdirectory one level below your working directory. 11. Read results file and plot results. Recall that p3 was initiated from a working directory which contained the excercise_08.db database file. The analysis, initiated from within MSC.Patran, created a new subdirectory with the same name as the Job Name; it should be named exercise_08/. By using Read Result in the Analysis form and Select Results File... you can filter down to the Job Name subdirectory and check for the existence of the results file

Read and plot results

Select the nr0.nrf.01 results file in the Available Files list box. Select OK. Select the Select Rslt Template File....in the Analysis form. In the Template to Import P/THERMAL Nodal Results form select the template named pthermal_1_nodal.res_tmpl from the Files list. Select OK. Select Apply in the Analysis form to read the chosen results file with the selected template.

MSC.Patran 312 Exercise Workbook - Release 2001

8-13

Read and plot results

To plot the results use the Results Application radio button. The default Action/Object should be Create/ Quick Plot. Select Fringe Result: Temperature. Hit Apply to quick plot the default Result Case and Fringe Result. To affect a better comparision use the Fringe Attributes icon to change the display and range. Select Display: Element Edges. Select Label/Style... Under Label/Style... select Label/Format: Fixed and use the slider bar to select 4 Significant figures, then select OK, and Apply. Select Range.../Define Range.../Create... Use a new Range Name: Compare with Number of Sub-Ranges: 7. Select OK. In the Range form select Data Method/From. In the spread sheet at the bottom of the form, select the 0th cell in the From column. In the Spreadsheet Input data line, type 600.0 and carriage return. Move to the next cell down and repeat these steps for 500, 400, 300, 200, 110, and 50. Select Calculate. Hit Apply. Finally select Assign Target Range to Viewport. Close all the sub-forms and click Apply on the Results form.

8-14

MSC.Patran 312 Exercise Workbook - Release 2001

Temperature Dependent Material Properties

WORKSHOP 8

12. Compare the results to the analytical solution.

Compare results

Shown below is the temperature contours derived by K. C. Chang and V. J. Payne.

: temperature-independent : temperature-dependent material 2

110

300

400

500

0.4

interface 200

material 1

0.5

0.3 0.2

50

0.1 0.0 0.0

0.1

13.

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0

Quit MSC.Patran.

Select File on the Menu Bar and select Quit from the dropdown menu.

MSC.Patran 312 Exercise Workbook - Release 2001

Quit MSC.Patr

8-15

Quit MSC.Patran

8-16

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 9

Thermal Analysis of the Hybrid Microcircuit

Objective: ■

In this exercise you complete a steady state thermal analysis of the 3D hybrid microcircuit.

MSC.Patran 312 Exercise Workbook - Release 2001

9-1

9-2

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 9

Thermal Analysis of the Hybrid Microcircuit

Model Description: In this exercise complete the analysis of a hybrid microcircuit which is subjected to a bench functional test. The hybrid is clamped to a test fixture which is chilled by iced water. The microcircuit is continuously flushed by a dry nitrogen purge at 21oC. During functional testing, which takes approximately 1 hour, the entire hybrid dissipates 8 watts. Each device dissipates a constant wattage, as listed. The goal of the analysis is to verify that all device temperature shall remain below 50oC.

Exercise Overview: ■

Open the existing database named microcircuit.db.

■

Use Finite Elements/Create/Node/Edit to create the two fixed temperature boundary nodes.

■

With Display/Finite Elements... or the equivalent Tool Bar function increase the display size of nodes to facilitate boundary definition.

■

Use Loads/BCs/Create/Temperature/Nodal with Option: Fixed to set the boundary node temperatures.

■

Use Loads/BCs/Create/Convection with Option: Fixed Coefficient to apply the contact and nitrogen flow heat transfer coefficients.

■

Post only the device_and_solder group and use the middle mouse button or various Viewing functions to expose the individual device surfaces.

■

Use. Loads/BCs/Create/Heating with Option: Template, Volumetric Heat to apply the heating load to the individual devices.

■

Select Analysis to prepare and to submit the model for analysis and to Read Results.

■

Post hybrid_fem, select an isometric_view, select Results, and review results data.

■

Quit MSC.Patran.

MSC.Patran 312 Exercise Workbook - Release 2001

9-3

Hybrid microcircuit boundary conditions

Hybrid microcircu it boundary conditions

Figure 1-Boundary Conditions h=8 w/m2-oC

h=1000 w/m2-oC

Nitrogen Flow Node 9998 21oC

Cold Plate Node 9999 0oC

Figure 2-Device Position 0.50w R1 1.00w R3

0.75w R2 0.25w R4 Total 8.00 watts

3.00w 0.50w 1.50 w 0.50w V4 V2 V3 V1

Table 2-Device Heat Generation

9-4

3

Device R1 R2 R3 R4

w/m 0.167E+09 0.250E+09 0.333E+09 0.083E+09

V1 V2 V3 V4

1.500E+09 0.250E+09 0.750E+09 0.250E+09

MSC.Patran 312 Exercise Workbook - Release 2001

Thermal Analysis of the Hybrid Microcircuit

WORKSHOP 9

Exercise Procedure: 1.

Open the existing database named microcircuit.db.

Within your window environment change directories to the microcircuit.db working directory. Run MSC.Patran by typing p3 in your xterm window.

Open an existing database

Next, select File from the Menu Bar and open the existing microcircuit database. File Open... Database List

microcircuit.db

OK MSC.Patran will open a Viewport and change various Control Panel selections from a ghosted appearance to a bold format. 2.

Create the two fixed temperature boundary nodes.

Select Viewing from the Menu Bar or use the Tool Bar Right Side View icon to change to a side_view of the model hybrid_fem entities.

Create 2 boundary nodes

Viewing Named View Options... Select Named View

side_view

Close Select the Finite Elements Applications radio button. Create two nodes which are not associated with geometry. The first node is numbered 9998.

◆ Finite Elements Create/Node/Edit Node ID List

9998

Associate with Geometry Node Location List

[0.01 0.01 0.002]

Apply

MSC.Patran 312 Exercise Workbook - Release 2001

9-5

Change display and picking preferences

The second node is numbered 9999.

◆ Finite Elements Create/Node/Edit Node ID List

9999

Associate with Geometry Node Location List

[0.01 0.01 -0.007]

Apply

3.

Change display and picking

Increase the display size of nodes and picking preferences to facilitate boundary definition.

Increase the display size of nodes and modify the Picking Preferences to facilitate the application of boundary condition. Use either Display/Finite Element/Node Size or the associated Tool Bar icon to change the node size. Display Finite Elements... Node Size (Use Slider Bar)

6

Apply Cancel And, select Preference/Picking... to change the Rectangle/Polygon picking method to Enclose Centroid. Preferences Picking...

◆ Enclose Centroid Close Select Display/ Load/BC/Element Props /Vectors... to facilitate viewing boundary conditions. Display Load/BC/Elem. Props... Show LBC/El. Prop Values

9-6



MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 9

Thermal Analysis of the Hybrid Microcircuit

Vectors/Filters... 0.05

Scale Factors:

Apply Cancel Apply Cancel 4.

Fix the boundary node temperatures.

Begin applying boundary conditions. Select the Loads/BCs Applications radio button.Create a fixed temperature boundary named Cold_plate.

Fix nodal boundary temperature

◆ Loads/BCs Create/Temperature/Nodal Option:

Fixed

New Set Name

Cold_plate

Input Data... In the Input Data form define the fixed temperature. 0.0

Fixed Temperature

OK Select Application Region... In the Select Applications Region form pick node 9999.

◆ FEM Select Nodes



Add OK Apply

MSC.Patran 312 Exercise Workbook - Release 2001

9-7

Apply convection boundary conditions

Repeat this process for a New Set Name Nitrogen with a fixed temperature of 21.0 applied to Node 9998. New Set Name

Nitrogen

Input Data... Fixed Temperature

21.0

OK Select Application Region...

◆ FEM Select Nodes



Add OK Apply The display should highlight each node and append the fixed temperature. On some displays the symbol and value may be difficult to discern.

Apply convectio n boundary

5.

Apply contact and nitrogen flow heat transfer coefficients.

Create two convective boundary conditions with the Use Correlations option and the heat transfer coefficients provided in Figure 1. Name the first set nitrogen_flow and apply the boundary condition to all of the element free faces on the top and sides of hybrid_fem.

◆ Loads/BCs Create/Convection/Element Uniform Option:

Fixed Coefficient

New Set Name

nitrogen_flow

Target Element Type

3D

Region 2

Nodal

Input Data... In the Input Data form provide the convection coefficient and fluid node association. Convection Coefficient

8.0

OK Select Application Region... 9-8

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 9

Thermal Analysis of the Hybrid Microcircuit

In the Select Applications Region form select all the free faces of the top and sides of the model. Exclude the bottom of the model by not enclosing it in the dragged rectangle.

◆ FEM Application Region / Select 3D Element Faces



Add Coupling Region / Select Nodes



Add OK Apply

Y

Z

X

MSC.Patran 312 Exercise Workbook - Release 2001

9-9

Apply convection boundary conditions

Repeat this process for a New Set Name heat_sink with a convection coefficient of 1000.0 applied to the bottom surface of the hybrid_fem. heat_sink

New Set Name

Input Data... Convection Coefficient

1000.0

OK Select Application Region...

◆ FEM Application Region / Select 3D Element Faces



Add Coupling Region / Select Nodes



Add OK Apply

Y

Z 9-10

X

MSC.Patran 312 Exercise Workbook - Release 2001

Thermal Analysis of the Hybrid Microcircuit

WORKSHOP 9

6.

Post only the device_and_solder group and rotate to a view which shows the top device elements

Post only device_an d_solder

Select Group/Post... and Reset Graphics to facilitate applying volumetric heat loads. Group Post... Select Groups to Post

device_and_solder

Apply Cancel Reset Graphics

Select Viewing from the Menu Bar or use the Tool Bar Iso 1 View icon to change to a isometric_view of the device_fem entities. Viewing Named View Options... Select Named View

isometric_view

Close 7.

Apply device volumetric heat loads.

Apply device volumetric heat loads

Based on the data in Table 2 apply volumetric heat loads to R1 through V4, the surface mounted components. The heat load should be placed only on the top layer of elements, the silicon devices.

◆ Loads/BCs Create/Heating/Element Uniform Option:

Template, Volumetric Heat

New Set Name

R1

Target Element Type

3D

Input Data... MSC.Patran 312 Exercise Workbook - Release 2001

9-11

Apply device volumetric heat loads

Vol Heat Generation

0.167E+09

OK Select Application Region...

◆ FEM Select 3D Elements



Add OK Apply

Repeat the application for New Set Names R2 through V4. Use Figure 2 on page 9-4 to correlate heat load to device locations. 9-12

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 9

Thermal Analysis of the Hybrid Microcircuit

The continuous display of LBC markers, vectors and their values should have provided positive indication of the correct application of the LBC’s. If you would like to further verify that the two fixed temperature, two heat transfer coefficient, and eight volumetric heating rate LBC’s are correctly applied use the Show Tabular, Plot Contours, and Plot Markers Action: selections in the Load/Boundary Conditions form. You may also wish to Group/Set Current... different groups to facilitate this LBC’s check. After completing LBC’s verification Group/Set Current... hybrid_fem. Group Post... Set Groups to Post

hybrid_fem

Apply Cancel Reduce the node size using the Node Size icon and reset graphics defaults using the Broom icon.

8.

Prepare and submit the model for analysis.

Select the Analysis Applications radio button to prepare the analysis. Move through each of the five parameter forms reviewing and changing the settings or selections, if necessary, as shown below. The analysis will be submitted by selecting Apply in the Analysis form.

Prepare and run analysis

◆ Analysis Analyze/Full Model/Full Run Solution Parameters... Calculation Temperature Scale

◆ Celsius

Solver Option

1, Weakly Nonlinear Solution

OK Output Requests... MSC.Patran 312 Exercise Workbook - Release 2001

9-13

Read and plot results

Units Scale for Output Temperatures

◆ Celsius

OK Apply

Read and plot results

9.

Read results file and plot results.

From within MSC.Patran the only indication that the analysis has successfully finished is the existence of an nrX.nrf.01 results file in a subdirectory one level below your working directory. Recall that p3 was initiated from a working directory which contained the microcircuit.db database file. The analysis, initiated from within MSC.Patran, created a new subdirectory with the same name as the Job Name; it should be named microcircuit/. By using Read Result in the Analysis form and Selecting Results File... you can filter down to the Job Name subdirectory and check for the existence of the results file.

◆ Analysis Read Results/Result Entities Select Results File... Directories

/microcircuit

Filter Available Files

nr0.nrf.01

OK Select Rslt Template File... Files

pthermal_1_nodal.res_tmpl

OK Apply To plot the results to posted FEM use the Results Application radio button.

◆ Results Create/Quick Plot

9-14

Select Result Cases

TIME: 0.0000000000D+00 S...

Select Fringe Result

Temperature,

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 9

Thermal Analysis of the Hybrid Microcircuit

Select the Fringe Attributes icon.

Display:

Element Edges

Label Style... Label Format:

Fixed

Significant figures

3

OK Apply The model should now appear as shown on the front panel of this exercise. What is the maximum reported temperature? Is it at or below the required maximum of 50oC?

10. Quit MSC.Patran To stop MSC.Patran select File on the Menu Bar and select Quit from the drop-down menu.

MSC.Patran 312 Exercise Workbook - Release 2001

Quit MSC.Patr

9-15

Quit MSC.Patran

9-16

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 10

Time Dependent Boundary Conditions

Objective: ■

Model an aluminum plate.

■

Use microfunctions to apply time dependent boundary conditions to the plate corners.

■

Run a transient analysis to produce time dependent results.

MSC.Patran 312 Exercise Workbook - Release 2001

10-1

10-2

MSC.Patran 312 Exercise Workbook - Release 2001

Time Dependent Boundary Conditions

WORKSHOP 10

Model Description: In this exercise you will define MACROs and microfunctions. MACRO definitions are edited into a template.dat.apnd file which you create in the same directory as your database. MACRO definitions link Template ID’s (TID’s) which are applied in the Loads/BCs form to Microfunction ID’s (MFID’s) which are defined in the Fields form. A microfunction can be a function of time or various temperature functions. This provides a mechanism for defining time or temperature varying heat load or temperature boundary conditions. Only constant or spatially varying loads or boundary conditions can be defined directly in the Loads/BCs forms. In this exercise we will sample three of the available microfunctions: a sine wave, a flip-flop function and a linearly interpolated data table. These functions are applied to three of the four corners of an aluminum plate modelled from shell elements. The fourth plate corner will have a constant boundary temperature. T121

T111

Figure 1

t 0 30 60 120 210 360

T111

t T121 =

100 125 160 160 100 100

111

t if t < 60 100 150 if 60< t < 180 100 if t > 180

{

0.15 m 121 Aluminum Plate 0.01 m thick

0.15 m

(MID =1)

T11

T1 1

t T1 = 100

11

t T11 = 15 sin(4*Pi*t/360 + 3*Pi/2) + 115 MSC.Patran 312 Exercise Workbook - Release 2001

10-3

Open a new database

Exercise Overview: ■

Create a new database named exercise_10.db. Set Tolerance to Default, and the Analysis Code to MSC/THERMAL.

■

Create a 0. 15m x 0.15m plate surface.

■

Mesh the surface with an IsoMesh of quad4 elements, global edge length of 0.015.

■

Apply element properties to the quad4’s defining them as shell elements having a material name (MID) of 1 and a thickness of 0.01m.

■

Create 3 time dependent microfunctions using Fields and Create/Non Spatial/General.

■

Define 4 temperature boundary condition in Loads/BC’s, 1 fixed nodal temperature in the lower left corner of the plate and 3 variable nodal temperatures on the remaining corners.

■

Use the new Analysis/Build Template to create the MACRO definitions in the template.dat .apnd file.

■

Prepare and submit the model for analysis specifying that it is a transient analysis from t=0s to t=360s with output each 30s, that the global initial temperature is 100oC, and that all calculations and output should be oC.

■

Read the results files using Shareware and plot results for several time steps. Do not delete the database from your directory since it will be used in a future exercise.

■

Quit MSC.Patran.

Exercise Procedure: Open a new database

1.

Open a new database named exercise_10.db.

Within your window environment change directories to a convenient working directory. Run MSC.Patran by typing p3 in your xterm window. Next, select File from the Menu Bar and select New… from the drop-down menu. Assign the name exercise_10.db to the new database by clicking in the New Database Name box and entering exercise_10. Select OK to create the new database. File

10-4

MSC.Patran 312 Exercise Workbook - Release 2001

Time Dependent Boundary Conditions

WORKSHOP 10

New... exercise_10

New Database Name

OK MSC.Patran will open a Viewport and change various Main Form selections from a ghosted appearance to a bold format. When the New Model Preferences form appears on your screen, set the Tolerance to Default, and the Analysis Code to MSC/THERMAL. Select OK to close the New Model Preferences form. Tolerance

◆ Default

Analysis Code

MSC/THERMAL

OK 2.

Create a 0.15m x 0.15m plate surface.

Select the Geometry Applications radio button. Create a surface using the following Action, Object, and Method. Click in the appropriate list boxes to edit the default values and change them to values listed below.

Create plate geometry

◆ Geometry Create/Surface/XYZ Vector Coordinate List



Apply The resulting model is shown below.

Y Z

X

MSC.Patran 312 Exercise Workbook - Release 2001

10-5

IsoMesh the surfaces

3.

IsoMesh the surfaces

Mesh the surface with an IsoMesh of quad4 elements, global edge length of 0.015.

Select the Finite Elements Applications radio button. Set the Action, Object, and Type to Create/Mesh/Surface. Change the Global Edge Length to 0.015 and select Surface 1 for inclusion in the Surface List.

◆ Finite Elements Create/Mesh/Surface Global Edge Length

0.015

Surface List



Apply Use the Tool Bar Label Control icon to turn on node labels only. First select

then

Close The display should now appear as shown below.

10-6

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 10

Time Dependent Boundary Conditions

4.

Apply element properties to the Quad4’s defining them as shell elements having a Material Name (MID) of 1 and a thickness of 0.01m.

Apply element properties

Select the Properties Applications radio button. Set the Action, Dimension, and Type to Create/2D/Shell. Enter Property Set Name Prop1. Select the Input Properties... box. Click in the Material Name box and enter 1. Enter 0.01 in the Shell Corner Thickness list box. Select OK to close the form. Click in the Select Members box and select Surface 1 in the viewport. Select Add then Apply in the Element Properties form to complete the element property definition.

◆ Properties Create/2D/Shell Prop1

Property Set Name

Input Properties... Material Name

1

Shell Corner Thickness

0.01

OK

Select Members

Add Apply

5.

Create 2 time dependent microfunctions using Fields and Create/Non Spatial/General.

Microfunctions are created in the Fields form using the Action/Object/ Method Create/Non Spatial/General. After selecting Input Data. The General Field Input Data form will show the complete list of microfunctions in the Select Function Term: list box.

Create microfunctions

Figure 1 contains the data required for entry into the various microfunction forms. The entries and selection below will guide you through the process of creating the microfunctions. An image of each completed microfunction form is included to facilitate microfunction entry.

◆ Fields Create/Non Spatial/General Field Name

Tsine MSC.Patran 312 Exercise Workbook - Release 2001

10-7

Create micro-functions

Input Data... Select Function Term

mfid_sine_wave

Micro Function ID

11

P1 Value

15.0

P2 Value

0.034907

P3 Value

4.71239

P4 Value

115.0

OK OK Apply The Micro Function form should appear as shown below. Micro Function: Sine Wave Define Micro Function Option 3 Sine Wave F(X) = P1 * SIN(P2 * X + P3) + P4 Micro Function ID (MFID) 11

Micro Function Option 3

Micro Function Description

Independent Variable Type Time P1 Value 15

P2 Value 0.034907

P3 Value 4.712389

P4 Value 115.0

OK

10-8

Reciprocal Micro Function

Defaults

MSC.Patran 312 Exercise Workbook - Release 2001

Cancel

WORKSHOP 10

Time Dependent Boundary Conditions

Tflip_flop

Field Name

Input Data... Select Function Term

mfid_flip_flop

Micro Function ID

121

P1 Value

60.0

P2 Value

180.0

P3 Value

150.0

P4 Value

100.0

OK OK Apply The Micro Function form should appear as shown below. Micro Function: Flip Flop Function Define Micro Function Option 15 Flip Flop Function If P1 get_qtran

Note: If you receive a “command not found” error then it indicates that you do not have a path to P3.HOME. In this case type: > which p3 (response) > /bin/p3 11-14

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 11

Using Convection Correlations

Then type in: > /bin/get_qtran

(response) > Enter a problem directory name or to exit: > prob4 (response) > Enter a filename (* to copy all files) or to exit: > mat.dat.apnd (response) > Copying mat.dat.apnd

A mat.dat.apnd should now reside in your database subdirectory. This file contains more material properties than required. This will not adversely affect the analysis. Feel free to review the format and syntax of the mat.dat.apnd file. You can use this file as a boiler plate for creating your own material properties file data. The template.dat.apnd and mat.dat.apnd files are the only two files that may need to be created outside of the MSC.Patran in order to complete an analysis. As MSC.Patran evolves the creation of this files will be absorbed within the MSC.Patran interface. 11. Prepare and submit the model for analysis. Select the Analysis Applications radio button to prepare the analysis. Select the parameter forms reviewing and changing the settings as shown below. The analysis is submitted by selecting Apply in the Analysis form.

Prepare and run analysis

◆ Analysis Analyze/Full Model/Full Run Translation Parameters... OK Solution Parameters... Run Control Parameters... Initial Temperature =

300.0

Initial Temperature Scale

◆ Kelvin

OK MSC.Patran 312 Exercise Workbook - Release 2001

11-15

Read and plot results

OK Output Requests... Units Scale for Output Temperatures

◆ Kelvin

Nodal Results File Format... Select Thermal Entries to Output



OK Diagnostic Output

◆ Convection Resistors

OK OK Apply

Read and plot results

12. Read and plot the results. From within MSC.Patran the only indication that the analysis has successfully finished is the existence of an nr0.nrf.01 results file in a subdirectory one level below your working directory. P3 was initiated from a working directory which contained the exercise_11.db database. Applying the analysis created a new subdirectory with the same name as the Job Name, exercise_11/. By using Read Result in the Analysis form and Select Results File... you can filter down to the Job Name subdirectory and check for the existence of a results file.

◆ Analysis Read Results/Result Entities Select Results File... Directories

/exercise_11

Filter Available Files

nr0.nrf.01

OK Select Rslt Template File... Files

pthermal_nod_T.res_tmpl

OK Apply

11-16

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 11

Using Convection Correlations

There may be a warning message regarding Qmacro, select OK. OK Reduce the node size using Node Size icon.

After results are read in plot the results. To plot the results use the Results Application radio button. Select you results file.

◆ Results Create/Quick Plot Select Result Cases

TIME: 0.0000000000D+00 S...

Select Fringe Result

Temperature,

Select the Fringe Attributes icon.

Display:

Element Edges

Label Style... Label Format:

Fixed

Significant figures

4

OK Apply

The model should now appear as shown on the front panel of this exercise. Feel free to plot the value of the heat transfer coefficient (and other quantities). Select the Select Result icon.

MSC.Patran 312 Exercise Workbook - Release 2001

11-17

Quit MSC.Patran

To plot the heat transfer coefficient data: Select Result Case

Time: 0.0000000000D+00 S...

Select Fringe Results

Average Convection Coefficient

Apply The nodal averaged h’s are displayed in the viewport. To view detailed convection resistor data look in qout.dat.01 file in the Job Name subdirectory. Search for string “CONVECTIVE RESISTOR DATA.”

Quit MSC.Patr

11-18

13. Quit MSC.Patran To stop MSC.Patran select File on the Menu Bar and select Quit from the drop-down menu.

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 12

Analysis of a Fuel Nozzle Tip

Objective: ■

Model an axisymmetric slice of a fuel nozzle tip.

■

Apply advective, radiative, and convective boundary conditions.

■

Run a steady state analysis and display results.

MSC.Patran 312 Exercise Workbook - Release 2001

12-1

12-2

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 12

Analysis of a Fuel Nozzle Tip

Model Description: In this exercise you will create an axisymmetric model of a fuel nozzle tip. You will model the heat transfer contribution of the fuel flow by an advective boundary condition. The geometry and boundary conditions for the problem are shown below The interior surface of the nozzle across which the fuel flows must be coupled to the fuel flow with a heat transfer coefficient. Since the corresponding fluid sink will not be a single node but a series of nodes the usual Loads/BCs Create/Convection/Template, Convection form does not apply.

Figure 1 Geometry 5.0” .5” Nickel (MID = 243) 0.05”

Steel (MID = 379) 0.1”

Still Air at h = K/L = 7.0 BTU/hr ft2 °F

Boundary Conditions Forced Convection Air T = 1000°F h = 500 BTU/hr ft2 °F

Radiation from Flame Flame Temp = 4000°F ε = 0.8 Internal Radiation e = 0.80

Fuel In

h (dT)

Specific gravity = 0.78

Tin = 200 °F h (dT) = 1.0 at 0.0 °F and 500.0 at 800 °F m = 50 lbm/hr Cp = 0.57 BTU/lbm °F

MSC.Patran 312 Exercise Workbook - Release 2001

12-3

Exercise Overview:

12-4

■

Create a new database named exercise_12.db. Set Tolerance to Default, and the Analysis Code to MSC/THERMAL.

■

Create the nozzle, fluid stream, and Convective Quad geometry.

■

Verify that surface normals are consistent with RxZ reversing any surface normals which are not consistent with RxZ.

■

Mesh the model surfaces with an IsoMesh of Quad4 elements and the curve representing the fluid stream with Bar2 elements, global edge length of 0.100.

■

Use Finite Elements/Create/Node/Edit to create two ambient nodes 998 and 999 for the ambient and flame temperatures, respectively.

■

Equivalence the nodes at the mating surface edges.

■

Apply Thermal Axisymmetric element properties to the nozzle and Advection Bar element properties to the flow stream.

■

Convert fluid stream nodes to fluid nodes using Utilities and apply element properties for Convective Quad’s.

■

Create fuel convection coefficient as a factor of temperature difference.

■

Define three fixed temperature, two convective, and two radiative boundary condition in Loads/BC’s.

■

Create and post a group which does not contain the Convective Quad elements.

■

Use the new Analysis/Build Template function to create the CONV and VFAC definitions.

■

Create a mat.dat.apnd file containing the fuel mass flow Cp MPID data provided in Figure 1.

■

Prepare and submit the model for analysis specifying that it is steady state analysis including viewfactor and radiation resistor computations, for an axisymmetric model with unit conversions from inches to feet that all calculations and output should be in oF.

■

Read and plot the results.

■

Quit MSC.Patran.

MSC.Patran 312 Exercise Workbook - Release 2001

Analysis of a Fuel Nozzle Tip

WORKSHOP 12

Exercise Procedure: 1.

Open a new database named exercise_12.db.

Within your window environment change directories to a convenient working directory. Run MSC.Patran by typing p3 in your xterm window.

Open a new database

Next, select File from the Menu Bar and select New … from the drop-down menu. Assign the name exercise_12.db to the new database by clicking in the New Database Name box and entering exercise_12. Select OK to create the new database File New... New Database Name

exercise_12

OK MSC.Patran will open a Viewport and change various Control Panel selections from a ghosted appearance to a bold format. When the New Model Preferences form appears on your screen, set the Tolerance to Default, and the Analysis Code to MSC/THERMAL. Select OK to close the New Model Preferences form. Tolerance

◆ Default

Analysis Code

MSC/THERMAL

OK 2.

Create the nozzle, fluid stream, and Convective Quad geometry.

Select the Geometry Applications radio button. Create the first of two surfaces that represent the geometry of the outer nozzle shell using the following Action, Object, and Method.

Create the nozzle and fluid stream geometry

◆ Geometry Create/Surface/XYZ Auto Execute



Vector Coordinates List



Origin Coordinates List

[0 0.2 0]

Apply MSC.Patran 312 Exercise Workbook - Release 2001

12-5

Create the nozzle and fluid stream geometry

Use Tool Bar Show Labels icon to turn on labels.

To create the second surface change the Vector Coordinates List to . Click in the Origin Coordinates List and select Point 4 (the lower right corner of Surface 1).

◆ Geometry Create/Surface/XYZ Vector Coordinates List



Origin Coordinates List



Apply

Select Viewing/Scale Factors... to increase the scale of the model in the Ydirection. This will expand the model display to facilitate viewing, picking, and displaying results. Only the model display is scaled not the actual model dimensions. Scaling may throw the coordinate system symbol out of the display viewport. Viewing Scale Factors... Model Y

5.0

Apply Cancel

12-6

MSC.Patran 312 Exercise Workbook - Release 2001

Analysis of a Fuel Nozzle Tip

WORKSHOP 12

The resulting model is shown below.

2

3 1

5 2

1

4

6

To create the surfaces that will represent the geometry where the Steel and Still Air will reside set the Geometry form Action, Object, and Method to Transform/Surface/Translate. Click in the Translator Vector databox and then choose the following Tip and base points icon.

Click on Point 5 and Point 6 to define the translation vector. Next, set the Repeat Count to 2, click in the Surface List databox and drag a rectangle around Surface 1 and Surface 2 in the viewport.

◆ Geometry Transform/Surface/Translate Translation Vector



Repeat Count

2

Auto Execute Surface List



MSC.Patran 312 Exercise Workbook - Release 2001

12-7

Create the nozzle and fluid stream geometry

Apply The resulting model is shown below.

2 1 7

3 1 3 5

10

4 8 11

5 2 4 6

6 9 12

The flow of fuel within the nozzle will be modelled with advection bars. Create the two curves where the bars will be placed. Change the Action, Object, and Method to Create/Curve/XYZ. For the first curve set the Vector and Origin Coordinates List to, and [0 0 0] respectively.

◆ Geometry Create/Curve/XYZ Vector Coordinates List Auto Execute Origin Coordinates List

[0 0 0]

Apply To create the second curve set the Vector and Origin Coordinates List to and Point 14 respectively. Vector Coordinates List



Origin Coordinates List



Apply 12-8

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 12

Analysis of a Fuel Nozzle Tip

Create surfaces between Curve 1 and the lower edge of Surface 5 and between Curve 2 and the lower edge of Surface 6. These surfaces will support the Convection Quad elements. Set the Action, Object, and Method to Create/Surface/Curve. Select the 2 Curve Curve Option and click in the Starting Curve List box. Make sure that the Curve icon is highlighted in the Select Menu, then drag a rectangle around Curve 1 and 2. Select the Surface Edge icon then drag a rectangle around the lower edges of Surfaces 5 and 6.

◆ Geometry Create/Surface/Curve

Auto Execute Starting Curve List



Ending Curve List



Apply Now, delete Surface 3 in the air gap.

◆ Geometry Delete/Any Geometric Entity List



Apply Refresh the graphics.

MSC.Patran 312 Exercise Workbook - Release 2001

12-9

Verify surface normals and flow direction

The resulting model is shown below.

3.

Verify that surface normals are consistent with RxZ. Reverse any surface normals which are not consistent with RxZ.

Radiative boundary conditions modeled in an axisymmetric coordinate frame must have all element normals pointing in the RxZ (read R cross Z) direction. In this model, RxZ is in the global -Z direction. It is wise to verify the normal direction now since there are fewer surfaces than elements. This will facilitate viewing and reversing normals. Element normal will follow geometry normals in a 2D model. Alternatively, element normals can be reversed, if necessary, later in the modeling process. However, if LBC’s are applied to elements before the normals are reversed then when the element normals are reversed the LBC’s may be dropped from those elements and require review and reapplication. To verify normals change to an isometric view using the Tool Bar icon.

12-10

MSC.Patran 312 Exercise Workbook - Release 2001

Verify surface normals and flow

WORKSHOP 12

Analysis of a Fuel Nozzle Tip

Use Show/Surface/Normal. Drag a rectangle around all surfaces. In this model all surfaces normals must be reversed. Use Edit/Surface/Reverse, select all the surfaces, Draw Normal Vectors to verify reversal.

◆ Geometry Show/Surface/Normal Surface List



Apply Edit/Surface/Reverse Auto Execute Surface List



Apply Draw Normal Vectors Reset Graphics It is also prudent to verify the direction of the flow stream. Advection in an element flows in the local node 1 to node 2 direction. Unless reversed, the element local node 1/node 2 direction will follow the parent curve C1, or parametric, direction. Hence, it is sufficient to verify the C1 directions of Curve 1 and Curve 2. There is a toggle for displaying geometric parametric directions in Display/Geometry. Curves have only one parametric direction which is shown in the same color as the curve. Scaling may have offset the parametric marker from the curve but it’s color and relative length should facilitate identification. Display Geometry... Show Parametric Direction Apply Cancel

MSC.Patran 312 Exercise Workbook - Release 2001

12-11

Verify surface normals and flow direction

The resulting display is shown below.

Return to default Front view.

Remove parametric directions display. Display Geometry... Show Parametric Direction Apply Cancel

12-12

MSC.Patran 312 Exercise Workbook - Release 2001

Analysis of a Fuel Nozzle Tip

WORKSHOP 12

4.

Mesh the model surfaces with an IsoMesh of Quad4 elements and the curve representing the fluid stream with Bar2 elements, global edge length of 0.100.

IsoMesh the surfaces and fluid

Select the Finite Elements Applications radio button. Set the Action, Object, and Type to Create/Mesh/Surface. Change the Global Edge Length to 0.100 and click in the Surface List box. Drag a rectangle around all surfaces in the viewport.

◆ Finite Elements Create/Mesh/Surface Global Edge Length

0.100

Surface List



Apply Create Bar2 elements along Curves 1 and 2.

◆ Finite Elements Create/Mesh/Curve Global Edge Length

0.100

Curve List



Apply 5.

Use Finite Elements/Create/Node/Edit to create two ambient nodes 998 and 999 for the ambient and flame temperatures.

In the Finite Elements form create a boundary node which is not associated with geometry. The node is numbered 998. Locate the node at [2.5 0.3 0].

Create boundary nodes

◆ Finite Elements Create/Node/Edit Node ID List

998

Associate with Geometry



Auto Execute



Node Location List

[2.5 0.3 0]

MSC.Patran 312 Exercise Workbook - Release 2001

12-13

Create boundary nodes

Apply

Repeat for Node 999 located at [5.2 0.15 0].

Increase the display size of nodes. Use either Display/Finite Elements... or the associated Tool Bar icon to change the node size. Display Finite Elements... Node Size

9

Apply Cancel or,

Select Display/Entity Color/Label/Render.../Hide All Entity Labels or use the Tool Bar Labels Hide icon to remove all labels and unclutter the display. Display Entity Color/Label/Render... Hide All Entity Labels Apply Cancel or,

12-14

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 12

Analysis of a Fuel Nozzle Tip

The display should now appear as shown below.

6.

Equivalence the nodes at the mating surface edges.

Using the Finite Elements form set the Action/Object/Method to Equivalence/All/Tolerance Cube and select Apply to eliminate duplicate nodes created at geometric entity edges.

Equivalen ce nodes

◆ Finite Elements Equivalence/All/Tolerance Cube Apply 7.

Apply Thermal Axisymmetric element properties to the nozzle and Advection Bar element properties to the flow stream.

Use Tool Bar Label Control icon to turn on Surface labels. Close

Apply element properties to nozzle

Select the Properties Applications radio button. Set the Action, Dimension, and Type to Create/2D/Thermal Axisymmetric. Enter Property Set Name Nickel. Select the Input Properties... box. Click in the Material Name box and enter 243. Select OK to close the form.Click in the Select Members box

MSC.Patran 312 Exercise Workbook - Release 2001

12-15

Create fluid nodes and Convective Quads

and select Surfaces 1, 2, and 4 in the viewport using the shift-left mouse button. Select Add then Apply in the Element Properties form to complete the element property definition.

◆ Properties Create/2D/Thermal Axisymmetric Nickel

Property Set Name

Input Properties... 243

Material Name

OK

Select Members

Add Apply Repeat these steps for Steel, MID 379, on Surfaces 5 and 6. The two element property set names should now appear in the Property Set Name list box.

Create fluid nodes and Convective Quads

8.

Convert fluid stream nodes to fluid nodes using Utilities and apply element properties for Convective Quad’s.

Convective Quad elements must have at least one Fluid Node associated with each element. Fluid nodes are a 0D element type applied to selected nodes. There are two means of creating Fluid Nodes, using Element Properties or using Utilities. Choose one of the two following methods. Using Utilities: Utilities Thermal Create Node Type Elements... OK New Set Name

12-16

Fluid_nodes

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 12

Analysis of a Fuel Nozzle Tip

Select Nodes

Apply Cancel Or, using the Properties form:

◆ Finite Elements Create/Element/Edit Shape

Point

Node 1 =



Apply

◆ Properties Create/0D/Node Type Fluid_nodes

Property Set Name

Input Properties... “Fluid Node”

Value Type

OK Select Members (Click the Point Element from the select Menu.)



Add Apply Small triangles will mark each fluid node. Now Create/2D/Convective Quad elements on Surfaces 7 and 8 with a Template ID of 10. Later you will input the convection heat transfer coefficient in the template.dat.apnd file.

MSC.Patran 312 Exercise Workbook - Release 2001

12-17

Create fluid nodes and Convective Quads

Convective Quads have no physical reality in the model; they are a device for passing cross sectional area data, convection configuration data (GP’s), and fluid node data to the convection algorithm. When the Between Region option is expanded to include 2D dimensionality, the need for Convection Quads will be limited to passing data to user defined configurations.

◆ Properties Create/2D/Convective Quad Property Set Name

Conv_quads

Input Properties... [Template ID]

10

OK Select Members



Add Apply The last element property you will create will define the Bar2 elements as advective bars. Change the Dimension to 1D and the Type to Advection Bar. Enter Adv_bars for the Property Set Name and then click on the Input Properties… button. When the Input Properties form appears enter 1 for the Cp-MPID and 50 for the Mass Flow Rate. Create/1D/Advection bar Property Set Name

Adv_bars

Input Properties... [Specific Heat MPID]

1

Mass Flow Rate

50

OK Select Members



Add Apply Though the Specific Heat MPID appears in square brackets it is, in fact, not an optional entry. Even in a steady state analysis advective conductors are derived from the product of specific heat and mass flow rate. 12-18

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 12

Analysis of a Fuel Nozzle Tip

Five Existing Property Sets should now be listed in the Element Properties form. Adv_bars, Conv_quads, Fluid_Nodes, Nickel and Steel. Scroll through the list to verify it. 9.

Create fuel convection coefficient as a factor of temperature difference. Select the Fields application radial button. Use Create/ Material Property/General to create the variable h called h_fuel.

◆ Fields Create/Material Property/ General Field Name

h_fuel

Input Data... Select Function Term

mpid_indx_linr_tabl

Description - Property Table

fuel

Material Property ID (MPID)

1001

Temperature Units

Fahrenheit

Input Temperature Value

0.0

Enter Value, Function

1.0

Enter Input Temperature Value

800.0

Enter Value, Function

500.0

Enter OK OK Apply

MSC.Patran 312 Exercise Workbook - Release 2001

12-19

Apply boundary conditions

10. Define three fixed temperature, two convective, and two radiative boundary condition in Loads/BC’s.

Apply boundary conditions

Select the Loads/BCs Applications radio button. Create a fixed 1000oF nodal boundary temperature named T_air. In the Input Data form define the fixed temperature. In the Select Region form pick Node 998, located above the nozzle model.

◆ Loads/BCs Create/Temperature/Nodal Option:

Fixed

New Set Name

T_air

Input Data... Fixed Temperature

1000.0

OK Select Application Region... Geometry Filter

◆ FEM

Select Nodes



Add OK Apply Repeat these steps for a New Set Name T_flame of 4000 oF applied to Node 999, located to the right of the nozzle and for a New Set Name T_fuel of 200oF applied to Node 221, located at the lower left corner of the model at the fuel stream inlet. Create the ambient convection boundary condition. Use a New Set Name Amb_conv, a Convection Coefficient of 500.0, and a Fluid Node 998.

◆ Loads/BCs Create/Convection/Element Uniform Option

Template, Convection

New Set Name

Amb_conv

Target Element Type

2D

Input Data...

12-20

Convection Coefficient

500

Fluid Node ID



MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 12

Analysis of a Fuel Nozzle Tip

OK Select Application Region... Geometry Filter

◆Geometry

Select Menu

mv mat.dat.apnd 11_mat.dat.apnd Using the system editor, typically vi, create and edit a new file mat.dat.apnd in the directory which contains your database and where MSC.Patran is running. You will define MPID 1 for the specific heat property of the advective flow. There is an alternative method for creating MPID definitions. Recall, you can also use Fields/Material Property/General to accomplish this. Shown below is the final form of the mat.dat.apnd file created for this exercise. Make sure that there are no blank lines especially at the end of the file. Start typing from the first column and make sure to close the MPID definition with a slash (/). MPID 1 C F 1.0 MDATA 0.57 /

MSC.Patran 312 Exercise Workbook - Release 2001

12-27

Prepare and run analysis

14. Prepare and submit the model for analysis specifying that it is steady state analysis including viewfactor and radiation resistor computations, for an axisymmetric model with unit conversions from inches to feet that all calculations and output should be in oF.

Prepare and run analysis

Select the Analysis Applications radio button to prepare the analysis. Select the parameter forms reviewing and changing the settings as shown below. The analysis is submitted by selecting Apply in the Analysis form.

◆ Analysis Analyze/Full Model/Full Run Translation Parameters... Model Dimensionality

◆ Axisymmetric Geometry, R Z Co-ordinates

Radial, R Co-ordinate

◆ Yaxis ◆ Xaxis

Centerline, Z Co-ordinate

Perform Geometry Units Conversion From Units

inches

To Units

feet

File to Extract ndefined Materials:

3,mpidfph.bin (Btu-feet-lbm-hour)

OK Solution Type... Perform Viewfactor Analysis

OK Solution Parameters... Calculation Temperature Scale

◆ Fahrenheit

Run Control Parameters... Stefan-Boltzmann Constant

1.7140E-9 BTU/HR/FT2/R4

Initial Temperature =

1000.0

Initial Temperature Scale

◆ Fahrenheit

OK OK Output Requests...

12-28

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 12

Analysis of a Fuel Nozzle Tip

Units Scale for Output Temperatures

◆ Fahrenheit

Units Definition for Time Label

Hours

OK Submit Options... Make sure both Create ViewFactor Control FIle (vf.ctl) and Execute Viewfactor Analysis are selected. OK Apply 15. Read and plot the results. From within MSC.Patran the only indication that the analysis has successfully finished is the existence of an nrX.nrf.01 results file in a subdirectory one level below your working directory.

Read and plot results

P3 was initiated from a working directory which contained the exercise_12.db database. Applying the analysis created a new subdirectory with the same name as the Job Name, exercise_12/. By using Read Result in the Analysis form and Selecting Results File... you can filter down to the Job Name subdirectory and check for the existence of a results file.

◆ Analysis Read Results/Result Entities Select Results File... Directories

/exercise_12

Filter Available Files

nr0.nrf.01

OK Select Rslt Template File... Files

pthermal_1_nodal.res_tmpl

OK Apply

MSC.Patran 312 Exercise Workbook - Release 2001

12-29

Quit MSC.Patran

After results are read in plot the results. To plot the results use the Results Application radio button. Select you results file.

◆ Results Create/Quick Plot Select Result Cases

TIME: 0.0000000000D+00 S...

Select Fringe Result

Temperature,

Select the Fringe Attributes icon.

Display:

Element Edges

Label Style... Label Format:

Fixed

Significant figures

4

OK Apply The model should now appear as shown on the front panel of this exercise.

Quit MSC.Patr

12-30

16. Quit MSC.Patran To stop MSC.Patran select File on the Menu Bar and select Quit from the drop-down menu.

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 13

A Sprinkler System Hydraulic Analysis

Objective: ■

Model a schematic of a home sprinkler system.

■

Use microfunctions to apply pressure varying mass flow functions at the sprinkler heads.

■

Run a hydraulic analysis to evaluate the pressure drop and total mass flow through the system.

MSC.Patran 312 Exercise Workbook - Release 2001

13-1

13-2

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 13

A Sprinkler System Hydraulic Analysis

Model Description: In this exercise you will create schematic geometry which models a sprinkler system for a medium size lawn. The model is a schematic since the actual pipe lengths in the circuit will be defined via the Element Properties form. All fitting losses have been included as additions to pipe lengths. The home for which this sprinkler is designed can comfortably deliver 12 gallons per minute (GPM) of water at 42 psi through the existing main. Since both the volumetric flow through and the coverage from each sprinkler head are a function of pressure at the head, this analysis will determine whether the pressure at each head is above 30 psi and whether the entry volumetric flow demand is less than 12 GPM. All data provided yield an analysis in English Engineering units, lbf, lbm, s, feet. However here are some useful conversion factors for evaluating the results: 1 cu. ft. = 7.481 gal. and 1 sq. ft. = 144 sq. in.

Exercise Overview: ■

Create a new database named exercise_13.db. Set Tolerance to Default, and the Analysis Code to MSC/THERMAL.

■

Create flow network schematic geometry using the Geometry form Create and Transform Actions.

■

Create FEM entities. Create nodes matching geometric points and mesh curve with BAR2 elements.

■

Equivalence nodes.

■

Define element properties for 1D Flow network bar elements using IOPT=2 for automatic friction factor calculation.

■

Use Utilities/Thermal/Hydraulic Icon direction.

■

Create three NonSpatial/General fields which define the sprinkler head volumetric flow as a function of pressure.

■

Define inlet pressure and sprinkler head mass flow conditions.

■

Use Analysis/Build template.dat.apnd file.

■

Select Analysis to prepare and to submit the model for analysis and to Read Results.

■

Run the analysis and read the results into the database.

Template

to

to

check

create

flow

the

MSC.Patran 312 Exercise Workbook - Release 2001

13-3

Open a new database ■

Quit MSC/PATRAN.

Exercise Procedure: Open a new database

1.

Open a new database named exercise_13.db.

Within your window environment change directories to a convenient working directory. Run MSC.Patran by typing p3 in your xterm window. Next, select File from the Menu Bar and select New… from the drop-down menu. Assign the name exercise_13.db to the new database by clicking in the New Database Name box and entering exercise_13. Select OK to create the new database. File New... New Database Name

exercise_13

OK MSC.Patran will open a Viewport and change various Main Form selections from a ghosted appearance to a bold format. When the New Model Preferences form appears on your screen, set the Tolerance to Default, and the Analysis Code to MSC/THERMAL. Select OK to close the New Model Preferences form. Tolerance

◆ Default

Analysis Code

MSC/THERMAL

OK

Create network schematic geometry

2.

Create flow network schematic geometry using the Geometry form Create and Transform Actions.

Select the Geometry Applications radio button. Create points using the following Action, Object, and Method. Click in the appropriate list boxes to edit the default values and change them to values listed below. First, turn on the labels with the Show labels icon.

◆ Geometry 13-4

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 13

A Sprinkler System Hydraulic Analysis

Create/Point/XYZ [0 6 0]

Point List

Apply [6 0 0]

Point List

Apply [6 12 0]

Point List

Apply Now translate points using the following Action, Object, and Method. Click in the appropriate list boxes to edit the default values and change them to values listed below. Transform/Point/Translate Auto Execute Translation Vector



Repeat Count

5

Point List

Point 1

Apply Translation Vector



Repeat Count

2

Point List

Point 2, 3

Apply Translation Vector



Repeat Count

1

Point List

Point 5, 7

Apply Create curves using the following Action, Object, and Method. Click in the appropriate list boxes to edit the default values and change them to values listed below. Create/Curve/Point

MSC.Patran 312 Exercise Workbook - Release 2001

13-5

Create nodes and elements Starting Point LIst

Point 1

Ending Point LIst

Point 4

Apply

(Optional if your Auto Execute is turn on)

Repeat this create curves step for the following starting/ending point list. Table 1:

Create nodes and elements

Starting Point

Ending Point

Resulting Curve

4

5

2

5

6

3

6

7

4

7

8

5

4

2

6

4

3

7

5

13

8

6

9

9

6

10

10

7

14

11

8

11

12

8

12

13

3.

Create FEM entities. Create nodes matching geometric points and mesh curve with BAR2 elements.

Select the Finite Elements Applications radio button. Set the Action, Object, and Method to Create/Node/Edit. Select all of the geometry for inclusion in the Node Location List to duplicate the node number over the corresponding geometric point number.

◆ Finite Elements Create/Node/Edit Node Location LIst

13-6



MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 13

A Sprinkler System Hydraulic Analysis

Set the Action, Object, and Type to Create/Mesh/Curve. Change the Global Edge Length to 12.0 and select all curves for inclusion in the Curve List. Create/Mesh/Curve Global Edge Length

12.0

Curve List



Apply 4.

Equivalence nodes.

Select the Finite Elements Applications radio button if not already selected. Set the Action, Object, and Method to Equivalence/All/Tolerance Cube. Select apply to complete the function.

Equivalen ce Nodes

Equivalence/All/Tolerance Cube Apply The nodes bounding the interior cracks will be circled in the display and the Command Line will indicate that a number of nodes are deleted.

MSC.Patran 312 Exercise Workbook - Release 2001

13-7

Create micro-functions

The model should now appear as shown below.

5.

Create microfunctions

Define element properties for 1D Flow network bar elements using IOPT 2 for automatic friction factor calculation.

Select the Properties Applications radio button. Set the Action, Dimension, and Type to Create/1D/Flow network bar. Enter Property Set Name Entry. Select the Input Properties... box. In the Input Properties chart, follow the steps below and enter the values that correspond to the property name. Select OK to close the form.Click in the Select Members box and select Curve 1 in the viewport. Select Add then Apply in the Element Properties form to complete the element property definition.

◆ Properties Create/1D/Flow network bar Property Set Name

Entry

Input Properties...

13-8

[TID]

1

IOPT

2

[Pipe diameter]

0.0625

[Pipe length]

50.00

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 13

A Sprinkler System Hydraulic Analysis

[Pipe roughness]

0.0

[Fluid density]

62.46

[Fluid viscosity]

6.764e-4

OK

Select Members

Add Apply Repeat the above steps with the following property set names and change the property values that are listed, the rest should stay untouched. To select more than one curve in the Select Members box, hold down the key and select the curves. Set Name

Pipe length

Application Region

L_manifold

13.0

Curve 2, 5

L_riser

26.0

Curve 6, 7, 9, 10, 12, 13

S_manifold

7.0

Curve 3, 4

S_riser

8.0

Curve 8, 11

Scroll through the Existing Property Sets box to make sure there are five property sets. 6.

Use Utilities Thermal Hydraulic Icons to verify flow directions.

Verify Flow Directions

Utilities Thermal Hydraulic Icons... If a disclaimer message appears, click:

OK

Apply Clear Close 7.

Create 3 NonSpatial/General fields which define the sprinkler head volumetric flow as a function of pressure.

MSC.Patran 312 Exercise Workbook - Release 2001

Create Fields

13-9

Create Fields

In the Fields form use the Action/Object/Method Create/Non Spatial/ General. Enter Full-GPM in the Field Name box. After selecting Input Data the General Field Input Data form will show the complete list of microfunctions in the Select Function Term list box. The entries and selection below will guide you through the process of creating the microfunctions. An image of each completed microfunction form is included to facilitate microfunction entry. When modeling hydraulic networks the independent variable names remain the same on the General Field Input Data form; however, Temperature now refers to Pressure and any other independent variable choices other than Time or Temperature should be ignored.

◆ Fields Create/Non Spactial/General Field Name

Full_GPM

Input Data... Select Function Term

mfid_indx_linr_tabl

Micro Function ID

1100

Independent Variable Type

Temperature

Independent Variable, (X)

0.0

Value, Function(X)

0.0

Enter Independent Variable, (X)

2880.0

Value, Function(X)

1.67

Enter Independent Variable, (X)

4320.0

Value, Function(X)

2.19

Enter Independent Variable, (X)

5760.0

Value, Function(X)

2.35

Enter Independent Variable, (X)

7200.0

Value, Function(X)

2.7

Enter 13-10

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 13

A Sprinkler System Hydraulic Analysis

The Micro Function form should appear as shown below. Micro Function: Indexed Linear Interpolation

Define Micro Function Option 18 Indexed Linear Interpolation of a Data Table Micro Function ID (MFID) 1100

F(X)

5 4

3 1 2

6 7 8

X

Micro Function Option 18

Micro Function Description Independent Variable Type Temperature

Reciprocal Micro Function Bound Tables

Tabular Data Independent Variable 1 2 3 4 5

0.0 2880.0 4320.0 5760.0 7200.0

Dependent Value

0.0 1.67 2.19 2.35 2.7

OK OK Apply Field Name

Half_GPM

Input Data... Select Function Term

mfid_indx_linr_tabl

Defaults

(This clears the data form)

Micro Function ID

1050

Independent Variable Type

Temperature

Independent Variable, (X)

0.0

Value, Function(X)

0.0

Enter MSC.Patran 312 Exercise Workbook - Release 2001

13-11

Create Fields

Independent Variable, (X)

2880.0

Value, Function(X)

0.95

Enter Independent Variable, (X)

4320.0

Value, Function(X)

1.09

Enter Independent Variable, (X)

5760.0

Value, Function(X)

1.3

Enter Independent Variable, (X)

7200.0

Value, Function(X)

1.55

Enter

13-12

MSC.Patran 312 Exercise Workbook - Release 2001

A Sprinkler System Hydraulic Analysis

WORKSHOP 13

The Micro Function form should appear as shown below Micro Function: Indexed Linear Interpolation

Define Micro Function Option 18 Indexed Linear Interpolation of a Data Table

F(X)

5 4

1 2

6

3

7 8

X

Micro Function ID (MFID) 1050

Micro Function Option 18

Micro Function Description Independent Variable Type Temperature

Reciprocal Micro Function Bound Tables

Tabular Data Independent Variable 1 2 3 4 5

0.0 2880.0 4320.0 5760.0 7200.0

Dependent Value

0.0 0.95 1.09 1.3 1.55

OK OK Apply Field Name

Quarter_GPM

Input Data... Select Function Term

mfid_indx_linr_tabl

Default Micro Function ID

1025

Independent Variable Type

Temperature

Independent Variable, (X)

0.0

Value, Function(X)

0.0 MSC.Patran 312 Exercise Workbook - Release 2001

13-13

Create Fields

Enter Independent Variable, (X)

2880.0

Value, Function(X)

0.40

Enter Independent Variable, (X)

4320.0

Value, Function(X)

0.50

Enter Independent Variable, (X)

5760.0

Value, Function(X)

0.60

Enter Independent Variable, (X)

7200.0

Value, Function(X)

0.63

Enter The Micro Function form should appear as shown below Micro Function: Indexed Linear Interpolation

Define Micro Function Option 18 Indexed Linear Interpolation of a Data Table Micro Function ID (MFID) 1025

F(X)

5 4

6

3 1 2

7 8

X

Micro Function Option 18

Micro Function Description Independent Variable Type Temperature

Reciprocal Micro Function Bound Tables

Tabular Data Independent Variable 1 2 3 4 5

13-14

0.0 2880.0 4320.0 5760.0 7200.0

MSC.Patran 312 Exercise Workbook - Release 2001

Dependent Value

0.0 0.40 0.50 0.60 0.63

WORKSHOP 13

A Sprinkler System Hydraulic Analysis

OK OK Apply 8.

Define inlet pressure and sprinkler head mass flow conditions.

Begin applying boundary conditions. Select the Loads/BCs Applications radio button. Create a nodal pressure named Entry. In the Input Data form define the fixed pressure. In the Select Application Region form pick Point 1 located at the left most section of the geometry.

Apply boundary conditions

◆ Loads/BCs Create/Pressure/Nodal Option:

Fixed

New Set Name

Entry

Input Data... 6048

Fixed Pressure

OK Select Application Region...

Select Point

Add OK Apply Create a Variable, Mass Flow Rate named Full with Template Id 100 in the Input Data form. In the Select Application Region form pick Point 13, 14. Create/MassFlow Rate/Nodal Option:

Template

New Set Name

Full

Input Data... Mass Flow Rate Multiplier

1.0 MSC.Patran 312 Exercise Workbook - Release 2001

13-15

Apply boundary conditions

Template ID

100

OK Select Application Region... Select Points (hold down key)



Add OK Apply Repeat these steps for New Set Name Half with Template ID 50 on Point 9, 10 and Quarter with Template ID 25 on Point 2, 3, 11, 12. New Set Name

Half

Input Data... Mass Flow Rate Multiplier

1.0

Template ID

50

OK Select Application Region... Select Points (hold down key)



Add OK Apply New Set Name

Quarter

Input Data... Mass Flow Rate Multiplier

1.0

Template ID

25

OK Select Application Region... Select Points (hold down key)



Add OK Apply

13-16

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 13

A Sprinkler System Hydraulic Analysis

Change the view to an isometric view using the Iso 3 View icon.

With boundary conditions applied the model should appear as shown below

9.

Use Analysis/Build template.dat.apnd file.

Template

to

create

the

Beginning with MSC.Patran THERMAL V8, the template.dat.apnd file can be created from within the MSC.Patran interface. The ANALYSIS/BUILD TEMPLATE forms allow creating and editing all of the required templates.

In unix create template.d at.apnd file

Use the following chart to help you define the MACRO functions for the pressure boundary conditions assigned to all points. Table 2: TID#

Node 1

Node 2

scale_factor

mfid#

25

0

0

-0.139

1025

MSC.Patran 312 Exercise Workbook - Release 2001

13-17

In unix create template.dat.apnd file

Table 2: TID#

Node 1

Node 2

scale_factor

mfid#

50

0

0

-0.139

1050

100

0

0

-0.139

1100

Note: Nodes 1 and 2 are set to zero since the argument is time.

◆ Analysis Build Template Create Template File... Create/MACRO/Data Entry MACRO ID

25

MFID’s

1025

Scale Factor

-0.139

Apply A Template Entries form will appear, close it. Cancel MACRO ID

50

MFID’s

1050

Scale Factor

-0.139

Apply Cancel MACRO ID

100

MFID’s

1100

Scale Factor

-0.139

Apply Write File...

13-18

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 13

A Sprinkler System Hydraulic Analysis

In the File Option form, template.dat.apnd should be the default name in the File Name input box. OK Cancel Cancel Shown below is the final form of the template.dat.apnd file created for this exercise. Note that any comment lines must be started with an * in column 1 and make sure that there are no blank lines especially at the end of the file. *================ MACRO 25 1 0 0 -0.139 1025 MACRO 50 1 0 0 -0.139 1050 MACRO 100 1 0 0 -0.139 1100 *================

10. Prepare and submit the model for analysis. Select the Analysis Applications radio button to prepare the analysis. Select the parameter forms reviewing and changing the settings as shown below. The analysis is submitted by selecting Apply in the Analysis form.

Prepare and run analysis

◆ Analysis Analyze/Full Model/Full Run

◆ Perform Hydraulic Analysis

Solution Type... OK Solution Parameters...

◆ Fahrenheit

Calculation Temperature Scale

OK Output Requests... Units Scale for Output Temperatures

◆ Fahrenheit

MSC.Patran 312 Exercise Workbook - Release 2001

13-19

Read and plot results

Nodal Results File Format ..



OK OK Apply

Read and plot results

11. Read Result via the Analysis Form. From within MSC.Patran the only indication that the analysis has successfully finished is the existence of an npX.nrf.01 results file in a subdirectory one level below your working directory. P3 was initiated from a working directory which contained the exercise_13.db database. Applying the analysis created a new subdirectory with the same name as the Job Name; exercise_13/. By using Read Result in the Analysis form and Selecting Results File... you can filter down to the Job Name subdirectory and check for the existence of a results file.

◆ Analysis Read Results/Result Entities Select Results File... Directories

/exercise_13

Filter Available Files

np0.nrf.01

OK Select Rslt Template File... Files

pthermal_1_pnodal.res_tmpl

OK Apply Once he hydraulic results are read in, use Insight to post process the data. Insight provides a mechanism for increasing the diameter of the Bar 2 elements to view the results.

◆ Insight Create/Fringe Results Selection... Current Load Case(s) 13-20

2.1-Hydraulic Time: 0.0000

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 13

A Sprinkler System Hydraulic Analysis

Update Results Fringe Result

1.1-Pressure,

OK Fringe Attributes... Edge Width

5

Style

Cylinder

OK Target:

All Edges

Apply The result should now appear as shown on the front page of the exercise. Use the vi editor in UNIX to open the qout.dat.01 file in the exercise_13 Job Name subdirectory and determine whether the design requirements are met: an entry volumetric flow rate not to exceed 12 GPM and a sprinkler head pressure above 30 psi.

12. Quit MSC.Patran Do not delete the database when you finish this exercise it will be used in a future exercise. In that exercise we will improve execution time and reduce viewfactor file size. To stop MSC.Patran select File on the Menu Bar and select Quit from the drop-down menu.

MSC.Patran 312 Exercise Workbook - Release 2001

Quit MSC.Patr

13-21

Quit MSC.Patran

13-22

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 14

Midterm: Build a Simple 2 Plate Model

Objective: ■

Build a simple two plate model which meets specified requirements.

■

Prepare the model for analysis and open a UNIX shell to observe the file creation and analysis process.

■

Run the analysis and use UNIX and utility commands to monitor the progress of the analysis.

MSC.Patran 312 Exercise Workbook - Release 2001

14-1

14-2

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 14

Midterm Exam: Build a Simple 2 Plate

Model Requirements: The purpose of this exercise is to create a model with less guidance than has been provided in previous exercises. When the model is ready for analysis you will open a UNIX shell and observe the sequence of file creation paying special attention to files which provide feedback on the progress of the analysis. The model must meet the following requirements (see Figure on p 14-6) ■

2 - 1 x 1 x 0.001 meter plates with an MID of 353 (steel).

■

Plate surface normals shall face each other.

■

Each plate shall have a quadrant overlapping the other such that each plate has a corner point coincident with the center point of the other plate in Plan view.

■

The plates shall have a 0.05m gap between them.

■

Each plate shall have a mesh of 12x12 quad elements (global edge length 0.083).

■

Only one vertical edge of each plate shall have fixed boundary temperatures. The left most edge (x=0) shall be 0 degrees Celsius; the right most edge (x=1.5) shall be 150 degrees Celsius.

■

The two plates shall be thermally coupled by a single radiation boundary condition. Each plate has an emissivity of 0.1. Use a TID of 100 and an Enclosure ID of 1.

■

All boundary conditions and element properties shall be applied to geometry.

MSC.Patran 312 Exercise Workbook - Release 2001

14-3

Open a new database

Exercise Overview: ■

Open a new database named exercise_14.db.

■

Create a model which meets the specified requirements.

■

Review your model against the checklist of questions.

■

Open a UNIX shell before submitting the model for analysis.

■

Submit the model for analysis and use the commands described to monitor its progress.

■

Debug, if necessary and resubmit after deleting all the files in the jobnamed subdirectory.

■

Read in results file and plot results.

■

Quit MSC.Patran.

Exercise Procedure: Open a new database

1.

Open a new database named exercise_14.db.

Within your window environment change directories to a convenient working directory. Run MSC.Patran by typing p3 in your xterm window. Next, select File from the Menu Bar and select New… from the drop-down menu. Assign the name exercise_14.db to the new database by clicking in the New Database Name box and entering exercise_14. Select OK to create the new database. File New... New Database Name

exercise_14

OK MSC.Patran will open a Viewport and change various Main Form selections from a ghosted appearance to a bold format. When the New Model Preferences form appears on your screen, set the Tolerance to Default, and the Analysis Code to MSC/THERMAL. Select OK to close the New Model Preferences form.

14-4

Tolerance

◆ Default

Analysis Code

MSC/THERMAL

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 14

Midterm Exam: Build a Simple 2 Plate

OK 2.

Create a model which meets the specified requirements.

Based on what you’ve practiced, create the model according to the Model Requirements

Create a model

When completed model, should fit description shown on the next page. Note: The radiation boundary condition Input Data form has several list boxes for data entry. Despite the fact that all of the list boxes on the Input Data form appear to be required entries, you need only provide an Enclosure Id and a VFAC Template ID for this exercise. The other fields will be explored further in Exercise 21.

MSC.Patran 312 Exercise Workbook - Release 2001

14-5

Create a model

14-6

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 14

3.

Midterm Exam: Build a Simple 2 Plate Review your model against the checklist of questions.

Did you use the various view icons to verify the placement of geometry? Did you check surface normals using Geometry/Show/Surface/Normal?

Review your model

Is the element type 2D/Shell with Material 353 and thickness 0.001? Was your Target Element Type: 2D for the radiation boundary condition? Did you plot LBC markers to verify 2 fixed temperatures and radiation? Does the radiation LBC use VFAC Template ID=100 and Enclosure ID=1? Have you created template .dat.apnd with *================ VFAC 100 0.1 *================ and no blank lines? In the Analysis form have you set: Requested Calculation and Output Temperature scales to degrees Celsius? Have you requested Perform Viewfactor in Solution Type form?

4.

Open a UNIX shell before submitting the model for analysis.

Once the model is verified, the template.dat.apnd file is built, and the Analysis form is complete, iconify the MSC.Patran viewport and open a new UNIX shell to get a UNIX prompt. Use the UNIX ls and cd commands to get to the directory in which your database resides. When you are located in the directory type at the prompt: $ cd exercise_14

5.

Open a UNIX shell

but do not hit or enter

Submit the model for analysis and use the commands described to monitor its progress.

Return to the open Analysis form and check Apply. After the stops scrolling and the Heartbeat is again green , change focus to the UNIX window and use the cd

Submit the model

Command Line History Window

MSC.Patran 312 Exercise Workbook - Release 2001

14-7

Debug

exercise_14 command with a carriage return. Repeated execution of ls within the Job Name subdirectory will show you the progress of your analysis: Once the file vf.msg.01 appears, type: $ tail -f vf.msg.01 This will provide a continuous status of the viewfactor run. When viewfactor is complete it will end the status with a message, Successful Execution Completed. Use the c key combination to terminate the tail function. Repeatedly input a sequence of ls commands until a stat.bin file appears in the directory list. Once you the see the stat.bin file type: $ qstat c to monitor the progress of the network analysis. This command will self terminate after 20 repetitions or upon job completion. Monitor the data from the qstat command to determine the numerical status of the analysis. Check for the existence of an nr0.nrf.01 results file. If it exists the numerical analysis is complete and successful.

6.

Debug

Debug, if necessary, and resubmit after deleting all the files in the jobnamed subdirectory.

If Step 5 does not yield a results file then determine what went wrong. Is there a patqb.log file? If so, then is there a patq.msg file? If there is no patqb.log file then look in the MSC.Patran Command Line History Window or in the MSC.Patran interface for any error messages. If there is a patqb.log file and no patq.msg file then look for error messages in patqb.log. If there is a patq.msg file then look for error messages in it. If there are no error messages in the patq.msg file but this analysis requests that a viewfactor run be made then is there a vf.msg file? If there is a vf.msg file then look for error messages in it. For this analysis answering the above questions should provide a clue to the problem. 14-8

MSC.Patran 312 Exercise Workbook - Release 2001

Midterm Exam: Build a Simple 2 Plate

WORKSHOP 14

Once the error is found and resolved Repeat Steps 4 and 5. Remember that now many of the files will have an extension index which has been incremented by 1, e.g., vf.msg.01 to vf.msg.02. If it is convenient you may delete all the files from the exercise_14 Job Named subdirectory prior to resubmitting the analysis. 7.

Read in results file and plot results.

From within MSC.Patran the only indication that the analysis has successfully finished is the existence of an nrX.nrf.01 results file in a subdirectory one level below your working directory.

Read and plot results

Recall that p3 was initiated from a working directory which contained the microcircuit.db database file. The analysis, initiated from within MSC.Patran, created a new subdirectory with the same name as the Job Name; it should be named exercise_14/. By using Read Result in the Analysis form and Select Results File... you can filter down to the Job Name subdirectory and check for the existence of the results file.

◆ Analysis Read Results/Result Entiies Select Results File... Directories

/exercise_14

Filter Available Files

nr0.nrf.01

OK Select Rslt Template File... Files

pthermal_1_nodal.res_tmpl

OK Apply To plot the results to posted FEM use the Results Application radio button.

◆ Results Create/Quick Plot Select Result Cases

TIME: 0.0000000000D+00 S...

Select Fringe Result

Temperature,

MSC.Patran 312 Exercise Workbook - Release 2001

14-9

Quit MSC.Patran

Select the Fringe Attributes icon.

Display:

Element Edges

Label Style... Label Format:

Fixed

Significant figures

4

OK Apply The model should now appear as shown on the front panel of this exercise.

Quit MSC.Patr

14-10

8.

Quit MSC.Patran.

To stop MSC.Patran select File on the Menu Bar and select Quit from the drop-down menu.

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 15

User Supplied Subroutines

Objective: ■

Create a user subroutine UHVAL that computes the values for the heat transfer coefficient.

MSC.Patran 312 Exercise Workbook - Release 2001

15-1

15-2

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 15

User Supplied Subroutines

Model Description: In this exercise the Convection Correlation will be supplied by the user. You will write the necessary code to evaluate the Convection Correlation in the user subroutine UHVAL. This Qtran subroutine will compute the values for the heat transfer coefficient and return those values to the main program. An iron slab is modeled in 2-dimensions. A heat flux of 1000w/m2 is imposed on the bottom edge of the slab. The top surface convects heat to the ambient temperature at 300K with a heat transfer coefficient defined by a user supplied subroutine. Tamb = 300 K

1m X 10m

Iron

Heat flux

1000W/m2

Exercise Overview: ■

Start MSC.Patran and create a new database named, exercise_15.db.

■

Create the 2D model geometry.

■

Mesh the geometry with Quad4 elements and a Global Edge Length of 0.2.

■

Create an ambient node for convection boundary conditions.

■

Apply properties.

■

Create values for distance from the leading edge using Fields and Create/Spatial/PCL Function.

■

Define boundary conditions in Loads/BCs.

■

Copy ulib.f. MSC.Patran 312 Exercise Workbook - Release 2001

15-3

Open a new database ■

Modify and compile ulib.f.

■

Prepare and submit the model for analysis.

■

Read the results file and plot temperature an heat transfer coefficient results.

■

Quit MSC.Patran.

Exercise Procedure: Open a new database

1.

Open a new database named exercise_15.db.

Within your window environment change directories to a convenient working directory. Run MSC.Patran by typing p3 in your xterm window. Next, select File from the Top Menu Bar and select New… from the dropdown menu. Assign the name exercise_15.db to the new database by clicking in the New Database Name box and entering exercise_15. Select OK to create the new database File New... New Database Name

exercise_15

OK MSC.Patran will open a Viewport and change various Control Panel selections from a ghosted appearance to a bold format. When the New Model Preferences form appears on your screen, set the Tolerance to Default, and the Analysis Code to MSC/THERMAL. Select OK to close the New Model Preferences form. Tolerance

◆ Default

Analysis Code

MSC/THERMAL

OK

Create plate geometry

15-4

2.

Create the 2D model geometry.

To create the Surface that will represent the geometry of the 2D-model click on Geometry in the Main Window and set the Action, Object, and Method respectively to Create, Surface, and XYZ. Change the Vector Coordinates List to and click on the Apply button to create the Surface.

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 15

User Supplied Subroutines

◆ Geometry Create/Surface/XYZ Vector Coordinate List



Apply 3.

Mesh the surface with an IsoMesh of quad4 elements, global edge length of 0.2.

Select the Finite Elements Applications Radio Button and set the Action, Object, and Type respectively to Create, Mesh, and Surface. Enter, 0.2, for the Global Edge Length of the Quad4 elements you are now creating. Click in the Surface List box and then select Surface 1 in the viewport. Click on Apply to create the element.

IsoMesh the surfaces

◆ Finite Elements Create/Mesh/Surface Global Edge Length

0.2

Surface List



Apply

MSC.Patran 312 Exercise Workbook - Release 2001

15-5

Create Ambient Node

The display should now appear as shown below.

4.

Create Ambient Node

Create an ambient node for convection.

To create the ‘Ambient’ Node, click on Finite Elements in the Main Window. Set the Action, Object, and Type respectively to Create, Node, and Edit. Change the Node Id List to 999, set the Associate with Geometry option to off, and then click in the Nodal Location List. Select the Screen Position select icon in the Select Menu (the right-most icon) and then locate the Node somewhere above the model’s center. Click on Apply to create Node 999.

◆ Finite Elements Create/Node/Edit Node Id List

999

Associate with Geometry (toggle off) Node Location List



and

15-6

MSC.Patran 312 Exercise Workbook - Release 2001

User Supplied Subroutines

WORKSHOP 15

To better visualize the Node’s location, set the Node Radius to 6 (Display/ Finite Element). Or use the Tool Bar Node Size icon.

5.

Apply properties to the quad4’s defining them as 2D/Thermal 2D elements having a material MID of 18.

Apply element properties

Select the Properties Applications Radio Button. Set the Action, Dimension, and Method to Create/2D/Thermal 2D. Enter Property Set Name Prop1. Select the Input Properties... box. Click in the Material Name box and enter 18. Select OK to close the form.Click in the Select Members box and select Surface 1 in the viewport. Select Add then Apply in the Element Properties form to complete the element property definition.

◆ Properties Create/2D/Thermal 2D Property Set Name

Prop1

Input Properties... Material Name

18

Ok Select Members



Add Apply 6.

Create values for distance from the leading edge using Fields and Create/Spatial/PCL Function.

Spatial functions can be created in the Fields form using the Action/Object/ Method Create/Spatial/PCL Function.

Create microfunctions

◆ Fields Create/Spatial/ PCL Function Field Name

X_Dist

Scalar Function

’X+1.0

Apply

MSC.Patran 312 Exercise Workbook - Release 2001

15-7

Apply boundary conditions

Fields Action:

Create Spatial

Object: Method:

PCL Function

Existing Fields

Field Name X_Dist Field Type Scalar

Vector

Coordinate System Type Real Parametric Coordinate System Coord 0 Scalar Function ('X, 'Y, 'Z) 'X+1.0

Apply boundary conditions

7.

Define boundary condition in Loads/BCs.

To assign a heat flux of 1000 W/m2 to the bottom of Surface 1, click on Loads/BCs in the Main Window. Set the Action, Object, and Type respectively to Create/Heating(P Thermal)/Element Uniform. Enter, Bott_Surf_Flux, for the New Set Name and then set the Target Element Type to 2D. Select Input Data and enter 1000 for Heat Flux. Click on OK to close the Input Data form. Next, click on the Select Application Region button and set the Geometry Filter to Geometry in the Select Application Region form. Click in the Select Surfaces or Edges box and then select the edge selection icon (second icon from left) in the Select Menu. Select the bottom edge of Surface 1 in the viewport. Click on the Add and OK buttons to close the form. Click on the Apply button to create the Heat Flux boundary condition.

◆ Loads/BCs Create/Heating/Element Uniform

15-8

Option:

Flux, Fixed

New Set Name

Bott_Surf_Flux

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 15

User Supplied Subroutines 2D

Target Element Type:

Input Data... 1000

Fixed Heat Flux

OK Select Application Region... Select Menu



Select Surfaces or Edges



Add OK Apply

Next, Apply the 300K ambient temperature to Node 999 by clicking on Loads/BCs in the Main Window. Set the Action, Object, and Type respectively to Create, Temp(P Thermal), and Nodal. Switch the Option: to Fixed. Enter, Temp_amb, for the New Set Name. Click on the Input Data button and enter 300 for the Fixed Temperature. Click on OK to close the Input Data form. Next, click on the Select Application Region button. Set the Geometry Filter to FEM and then click in the Select Nodes box. Select Node 999 in the viewport. Click on the Add and OK buttons to close the form. In the Load/Boundary Conditions form click on the Apply button to assign the temperature to Node 999.

◆ Loads/BCs Create/Temperature/Nodal Option:

Fixed

New Set Name

Temp_amb

Input Data... 300

Fixed Temperature

OK Select Application Region...

MSC.Patran 312 Exercise Workbook - Release 2001

15-9

Apply boundary conditions

Geometry Filter

◆ FEM

Select Nodes



Add OK Apply To apply the (yet to be defined) Convection Coefficient click on Loads/BCs in the Main Window and set the Action, Object, and Type respectively to Create/Convection/Element Uniform, option: Template, Convection. Enter, Conv_Coeff_Spatial, in the New Set Name box and then change the Target Element Type to 2D. Next, click on the Input Data button, deselect “Fixed”, and enter the field X_Dist for the Conv GP2/GP3, a Convection Template ID of 1, and 999 for the Fluid Node ID. Click on OK to close the Input Data form. Click on the Select Application Region button in the Load/Boundary Condition form. Using the Select Application Region form select the top edge of Surface 1. Click on the Add and OK buttons to close that form. Finally click on Apply to assign the boundary condition.

◆ Loads/BCs Create/Convection/Element Uniform Option:

Template, Convection

New Set Name

Conv_Coeff_Spatial

Target Element Type:

2D

Input Data... Fixed Select Spatial Field...

(deselect)



Close CONV GP2/GP3

f:X_Dist

Convection Template ID

1

Fluid Node ID



OK Select Application Region... Geometry Filter 15-10

◆ Geometry

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 15

User Supplied Subroutines

Select Surfaces or Edges

Add OK Apply The current model is shown below.

Reduce the node size with the Node Size icon.

8.

Copy ulib.f.

Before you start programming the correlation, you will need to create a job name subdirectory. In the directory you are running MSC.Patran create a subdirectory named, exercise_15. Change to that subdirectory.

Copy ulib.f

You will now copy the ulib.f file from the MCS.Thermal library. To do so type get_qtran in the x-term window. Select utility and then ulib.f. %mkdir exercise_15 %cd exercise_15 %get_qtran MSC.Patran 312 Exercise Workbook - Release 2001

15-11

Modify and Compile ulib.f

Enter a problem directory name or to exit: utility Enter a filename or to exit: ulib.f %ls The ulib.f file contains, among others, the UHVAL subroutine and several other skeleton or sample subroutines. You will modify the UHVAL subroutine to create your own convection correlation.

9.

Modify and compile ulib.f.

Using the system editor open ulib.f and find the UHVAL subroutine. Three example configurations, with CFID’s of 1000, 1001, 1002, are already programmed but commented out. Note: The CFID’s will be defined in your Convection Template and are passed to the subroutine UHVAL with the three configurations. The following two values are always returned from the subroutine: i)

Conductance:

GVALH = h * Area

ii)

Heat transferred:

Q = GVALH * (T1 - T2) ))

In any Convection Configuration you prescribe, these two variables must be calculated and returned to the solver. To compute the h value (h=(Tsurf + 100)/L) the following two inputs are needed, RL, the distance from the leading edge to a particular element, and Tsurf the temperature of the element edge (surface). The distance from the leading edge will be passed from the field (X_Dist) input in the Convection Coefficient data box in the Loads/BCs form. The average distance from the slab’s leading edge to each element will be calculated from: RL = (GP2 + GP3)/2 GP2 and GP3 are the distance from the model’s leading edge to the leading and trailing edges of each element. GP1 is automatically passed from MSC.Patran as the cross sectional or surface area of each element. You will now write the FORTRAN code to calculate GVALH, Q, and H. With the systems editor open the ulib.f file. Scroll down the file or search for the second occurence of “UHVAL” in the file to locate the UHVAL subroutine. After the following line, C*C 15-12

1000

CONTINUE

MSC.Patran 312 Exercise Workbook - Release 2001

Modify and Compile ulib.f

WORKSHOP 15

User Supplied Subroutines

type the following lines of code while taking care to place all your code beyond column 7. Remember, this is FORTRAN. DOUBLE PRECISION RL, AREA RL = (GP(IRESIS,2) + GP(IRESIS,3))/2.0 AREA = GP(IRESIS,1) H = (T1+100.0)/RL GVALH = H*AREA Q = GVALH*(T1-T2) Save the file and quit your editor. As you scrolled down through UHVAL you may have noticed that Q, GVALH, H, T1, and T2 are already declared variables; hence, you only needed to declare RL and AREA. You will now compile your user routine. Delete any existing ulib.a you may have previously created, if any. Type in the command: %ulib ulib.f After successful compilation a new ulib.a will be present in your subdirectory. If any syntax errors scroll through the window during compilation then re-edit the file and repeat the above compilation step. To call the Convection Configuration you just created in UHVAL, you will need to create an appropriate convection template in the template.dat.apnd file. Use the new Analysis/Build Template function to accomplish this.

◆ Analysis Action:

Build Template

Create Template File... Create/CONV/Data Entry CONV ID

1

CFIG ID

1000

Apply Write File... OK

MSC.Patran 312 Exercise Workbook - Release 2001

15-13

Prepare and run analysis

Cancel Cancel Note: Since all of the GP values are supplied through the MSC.Patran interface and the calculation in UHVAL uses no material properties, no GP values and MPID’s have to be specified in the convection template.

10. Prepare and submit the model for analysis.

Prepare and run analysis

Select the Analysis Applications Radio Button to prepare the analysis. Select the parameter forms reviewing and changing the settings as shown below. The analysis is submitted by selecting Apply in the Analysis form .

◆ Analysis Analyze/Full Model/Full Run Translation Parameters...

2D Plane Geometry, X Y Co-ordinates (Unit Thickness in Z)

OK Output Requests... Nodal Results File Format... Select Thermal Entries to Output



OK OK Apply

11. Read results file and plot results.

Read Result

After completion of the analysis read and post-process the results. The resulting figure should look like the one in the title page of this exercise.

◆ Analysis Read Results/Result Entities Select Results File... Directories 15-14

/exercise_15

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 15

User Supplied Subroutines

Filter Available Files

nr0.nrf.01

OK Select Rslt Template File... Files

pthermal_nod_T.res_tmpl

OK Apply Warning OK To plot the results to posted FEM use the Results Application radio button.

◆ Results Create/Quick Plot Select Result Cases

TIME: 0.0000000000D+00 S...

Select Fringe Result

Temperature,

Select the Fringe Attributes icon.

Display:

Element Edges

Label Style... Label Format:

Fixed

Significant figures

4

OK Apply

MSC.Patran 312 Exercise Workbook - Release 2001

15-15

Quit MSC.Patran

Select the Select Result icon.

Select Fringe Result

Average Convection Coefficient

Apply

Quit MSC.Patr

15-16

12. Quit MSC.Patran To stop MSC.Patran select File on the Top Menu Bar and select Quit from the drop-down menu.

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 16

A Concentric Tube, Counterflow Heat Exchanger

Objective: ■

Demonstrate MSC.Thermal capabilities for gap convection problems.

■

Practice basic modeling skills using MSC.Patran.

MSC.Patran 312 Exercise Workbook - Release 2001

16-1

16-2

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 16

A Concentric Tube, Counterflow Heat Exchanger

Model Description: In this exercise you will create a simple 3D model representing the entry region of a concentric tube, counterflow heat exchanger. Owing to symmetry considerations only one-fourth of the heat exchanger configuration needs to be modeled. A team of university students is considering a makeshift heat exchanger, to cool and discard gaseous coolant from a small reactor. The heat exchanger is designed to “begin” at the reactor coolant plenum. In the event of an emergency, a safety valve would open to draw the coolant from the plenum into the exchanger (a process which will require approximately 60 seconds to complete). A secondary liquid coolant would then be used to decrease the temperature of the reactor coolant, before the reactor coolant enters a complex filtration process. The existing reactor coolant system is comprised of steel; and, the material proposed to contain the secondary coolant flow is simple lead. At the junction between the plenum and the heat exchanger, the gaseous fluid would exhibit a high mass flow rate at 350oC; the entry length variation of the convection coefficient between the steel and the gas is expected to follow: h = 200-13000*z3 w/m2K (where z is the distance from the plenum). The liquid coolant will flow between the steel coolant tube and its own lead housing, will be fully developed and is expected to exhibit a high convection coefficient (3000 w/m2K). The student’s prime concern with the design is the determination of the maximum temperature that the lead tube will exhibit after 60 sec of use. Lead Secondary Liquid Coolant Reactor Coolant Plenum 350oC

Steel Z h(z) Reactor Coolant

MSC.Patran 312 Exercise Workbook - Release 2001

16-3

Open a new database

Exercise Overview: ■

Create a new database named exercise_16.db.

■

Use the Create and Edit actions on the Geometry form to constuct a 2D representation of the heat exchanger.

■

Mesh the 2D geometry created in the previous step and use Sweep/Element/Extrude to develop he 3D FEM model.

■

Create 4 nodes to represent the spatial variation of the convection coefficient of the reactor coolant over the entry length.

■

Apply the appropriate Element Properties to the FEM model: Quad4’s - Steel MID 353; Hex8’s - Lead MID 21.

■

Create/Spatial/PCL Function to define the variation of the convection coefficient of the reactor coolant flow in the streamwise direction.

■

Apply a fixed temperature of 350oC to the nodes representing gasous coolant.

■

Create 2 Fixed Coefficient Convection Boundary Condtions.

■

Perform a Transient Analysis for 60s assuming a global initial temp of 25oC.

■

Prepare and submit the model for analysis.

■

Read results file and plot results.

■

Quit MSC.Patran.

Exercise Procedure: Open a new database

1.

Open a new database named exercise_16.db.

Within your window environment change directories to a convenient working directory. Run MSC.Patran by typing p3 in your xterm window. Next, select File from the Top Menu Bar and select New… from the dropdown menu. Assign the name exercise_16.db to the new database by clicking in the New Database Name box and entering exercise_16.

16-4

MSC.Patran 312 Exercise Workbook - Release 2001

A Concentric Tube, Counterflow Heat Exchanger

WORKSHOP 16

Select OK to create the new database. File New... exercise_16

New Database Name

OK MSC.Patran will open a Viewport and change various Control Panel selections from a ghosted appearance to a bold format. When the New Model Preferences form appears on your screen, set the Approximate Maximum Model Dimension to 0.07, and the Analysis Code to MSC/ THERMAL. Select OK to close the New Model Preferences form. Approximate Maximum Model Dimension

0.07

Analysis Code

MSC/THERMAL

OK 2.

Use the Create and Edit actions on the Geometry form to constuct a 2D representation of the heat exchanger.

Select the Geometry Applications Radio Button. Create a surface using the following Action, Object, and Method. Click in the appropriate list boxes to edit the default values and change them to values listed below.

Create 2D heat exchanger

◆ Geometry Create/Curve/2D ArcAngles Radius

0.05

Starting Angle

180

End Angle

270

Apply Radius

0.06

Apply Create/Surface/XYZ Vector Coordinates List



Apply

MSC.Patran 312 Exercise Workbook - Release 2001

16-5

Create 2D heat exchanger

Turn on the label by using the Tool Bar Show Labels icon.

Edit/Surface/Break Option:

Curve

Surface List:

Surface 1

Break Curve List

Curve 2

Apply Message! (delete original surface)

Yes

Delete/Any Geometric Entity List

Surface 3

Apply At any time during this exercise, use the Tool Bar Refresh graphics icon to refresh the graphics when necessary.

The resulting model is shown below.

16-6

MSC.Patran 312 Exercise Workbook - Release 2001

A Concentric Tube, Counterflow Heat Exchanger

WORKSHOP 16

3.

Mesh the surface with quad4 elements. Use the Paver and a global edge length of 0.006.

Select the Finite Elements Applications Radio Button. Set the Action, Object, and Type to Create/Mesh/Surface. Change the Global Edge Length to 0.006 and select Surface 2for inclusion in the Surface List.

Mesh the surfaces

◆ Finite Elements Create/Mesh/Surface Global Edge Length

0.006

Mesher

◆ Paver

Surface List

Surface 2

Apply Create/Mesh/Curve Global Edge Length

0.006

Curve List

Curve 1

Apply Sweep/Element/Extrude Mesh Control ... Number =

20

OK Extrude Distance

0.2

◆ Delete Original Elements Base Entity List



Apply Use the Tool Bar Hide Labels icon and Iso 1 View to get a clearer view of the graphics. Also, increase the size of the nodes by using the Tool Bar Node Size icon so the four boundary nodes will be more visible.

Hide Labels

Iso 1 View

Node Size

Fit View

MSC.Patran 312 Exercise Workbook - Release 2001

16-7

Create ambient nodes

The display should now appear as shown below.

4.

Create ambient nodes

Create 4 nodes to effect a spatial variation of the convection coefficient magnitude to represent a developing flow.

Using the Finite Elements form, create 4 boundary nodes which are not associated with geometry. The nodes are numbered 9996 to 9999. Click in the appropriate list boxes to edit the default values and change them to values listed below. Create/Node/Edit Node ID List

9996

Associate with Geometry Node Location List

[0 0 0]

Apply Node ID List

9997

Node Location List

[0 0 0.05]

Apply 16-8

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 16

A Concentric Tube, Counterflow Heat Exchanger

Node ID List

9998

Node Location List

[0 0 0.12]

Apply Node ID List

9999

Node Location List

[0 0 0.20]

Apply Rotate the display to verify the locations of the new nodes. Using the Iso 2 View, the model should appear as shown below.

Revert the display back to the Front View for the next section.

MSC.Patran 312 Exercise Workbook - Release 2001

16-9

Apply element properties

5.

Apply element properties

Apply two element properties to the elements using the material property MID’s 353 and 21.

In a typical modelling sequence the Materials Application radio button would be the next stop to define a material for application in Element Properties. However, MSC.Thermal includes a Material Properties Database which contains 971 materials with thermal properties already defined. We will use this database to facilitate the analysis. Select the Properties Applications radio button. Set the Action, Dimension, and Method to Create/2D/Shell. Enter Property Set Name Steel. Select the Input Properties... box. In the Input Properties form, click in the Material Name box and enter 353, and thickness of 0.005m. Select OK to close the form. First, select 2D element from the Select Menu Form. Click in the Select Members box and drag a rectangle around the model in the viewport. Select Add then Apply in the Element Properties form to complete the element property definition.

◆ Properties Create/2D/Shell Property Set Name

Steel

Input Properties... Material Name

353

Shell Corner Thickness

0.005

OK Select Members/Select Menu



Select Members



Add Apply Perform the same steps for outer lead portion, using Action, Dimension, andMethod to Create/3D/Thermal 3D Solid, Lead for the Property Set Name, 21 for the Material Name.

◆ Properties Create/3D/Thermal 3D Solid Property Set Name 16-10

Lead

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 16

A Concentric Tube, Counterflow Heat Exchanger

Input Properties... Material Name

21

OK Select Members/Select Menu



Select Members



Add Apply

6.

Create/Spatial/PCL Function to define the variation of the convection coefficient of the reactor coolant flow in the stream direction.

Create Function

◆ Fields Create/Spatial/PCL Function Field Name

convection_f_of_z

Scalar Function (‘X, ‘Y, ‘Z)

200-(13000*’Z*’Z*’Z)

Apply Show Select Field To Show

convection_f_of_z

Specify Range... Maximum

0.2

No. of Points

10

OK Apply

MSC.Patran 312 Exercise Workbook - Release 2001

16-11

Apply boundary conditions

The XY Result Window and Table should appear as shown below.

Close the window and table by clicking on the Unpost Current XYWindow. Cancel Unpost Current XYWindow 7.

Apply a fixed temperature of 350oC to the nodes representing gasous coolant.

Begin applying boundary conditions. Select the Loads/BCs Applications Radio Button. Create a fixed 350oC nodal boundary temperature named interior_flow. In the Input Data form define the fixed temperature. In the Select Applications Region form pick Node 9996 to 9999 located in the upper right corner of the display screen.

◆ Loads/BCs Create/Temperature/Nodal Option:

Fixed

New Set Name

interior_flow

Input Data... Fixed Temperature

350.0

OK 16-12

MSC.Patran 312 Exercise Workbook - Release 2001

Apply boundary conditions

WORKSHOP 16

A Concentric Tube, Counterflow Heat Exchanger

Select Application Region... Geometry Filter

◆ FEM

Select Nodes



Add OK Apply Create a between regions convection flow named inner_flow with the data show as follow. Create/Convection/Element Uniform Option:

Fixed Coefficient

New Set Name

inner_flow

Target Element Type:

2D

Region 2:

Nodal

Input Data... Select Spatial Field...



Close OK Select Application Region... Geometry Filter

◆ FEM

Select 2D Elements or Edges



Add Select Nodes



Add OK Apply MSC.Patran 312 Exercise Workbook - Release 2001

16-13

Apply boundary conditions

A green line should verify the newly defined association. Before creating the next convection condition, make sure that the polygon picking preference is set at Enclose entire entity. Preferences Picking... Rectangle/Polygon Picking

◆Enclose entire entity

Close Now, construct the next Between Regions Convection condition called outer_flow as follow. Create/Convection/Element Uniform Option:

Fixed Coefficient

New Set Name

outer_flow

Target Element Type:

3D

Region 2:

2D

Input Data... Convection Coefficient

3000

OK Select Application Region... Geometry Filter

◆ FEM

Coupling Method

Closest Approach

Select 3D Element Faces



Add Select 2D Elements or Edges



Add OK 16-14

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 16

A Concentric Tube, Counterflow Heat Exchanger

Apply The display should now appear as shown below.

8.

Prepare and submit the model for analysis.

Select the Analysis Applications Radio Button to prepare the analysis. Select the parameter forms reviewing and changing the settings as shown below. The analysis is submitted by selecting Apply in the Analysis form.

Prepare and run analysis

◆ Analysis Analyze/Full Model/Full Run Solution Type... Select Thermal Solution

◆ 1, Transient Run

OK Solution Parameters... Calculation Temperature Scale

◆ Celsius MSC.Patran 312 Exercise Workbook - Release 2001

16-15

Prepare and run analysis

Run Control Parameters... Stop Time =

60

Initial Temperature =

25.0

OK OK Output Requests... Units Scale for Output Temperatures

◆ Celsius

Print Interval Controls... Initial Print Interval =

20.0

OK OK Apply When the Heartbeat returns to green open a UNIX shell to monitor the progress of your job. Recall that the tools for monitoring your job are as follows: 1) cd - to change the current directory to the Job Name subdirectory, 2) tail - f patq.msg.01 - to monitor the generation of the input deck, 3) qstat l - to link the status file from each time step together and, 4) qstat c - to monitor the solver progress.

16-16

MSC.Patran 312 Exercise Workbook - Release 2001

A Concentric Tube, Counterflow Heat Exchanger

WORKSHOP 16

9.

Read results file and plot results.

From within MSC.Patran the only indication that the analysis has successfully finished is the existence of an nrX.nrf.01 results file in a subdirectory one level below your working directory.

Read and plot results

P3 was initiated from a working directory which contained the exercise_16.db database. Applying the analysis created a new subdirectory with the same name as the Job Name; exercise_016/. By using Read Result in the Analysis form and Selecting Results File... you can filter down to the Job Name subdirectory and check for the existence of a results file.

◆ Analysis Read Results/Result Entities Select Results File... Directories

/exercise_16

Filter Available Files

nr2.nrf.01

OK Select Rslt Template File... Files

pthermal_1_nodal.res_tmpl

OK Apply Change the display to the Iso 1 View, reduce the node size, and remove the BC vectors by using the Tool Bar Iso 1 View, Node Size, Reset graphics, Refresh graphic, and Fit View icons.

To plot the results to posted FEM use the Results Application radio button.

◆ Results Create/Quick Plot Select Result Cases

TIME: 4.0000000000D+01 S...

Select Fringe Result

Temperature,

MSC.Patran 312 Exercise Workbook - Release 2001

16-17

Quit MSC.Patran

Select the Fringe Attributes icon.

Display:

Element Edges

Label Style... Label Format:

Fixed

Significant figures

4

OK Apply The model should now appear as shown on the front panel of this exercise.

Quit MSC.Patr

16-18

10. Quit MSC.Patran To stop MSC.Patran select File on the Top Menu Bar and select Quit from the drop-down menu.

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 17

Analysis of a Fuel Nozzle Tip Using Convection Between Regions

Objective: ■

Model an axisymmetric slice of a fuel nozzle tip.

■

Apply advective, radiative, and convective boundary conditions.

■

Run a steady state analysis and display results.

MSC.Patran 312 Exercise Workbook - Release 2001

17-1

17-2

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 17

Analysis of a Fuel Nozzle Tip Using Convection Between Regions

Model Description: In this exercise you will create an axisymmetric model of a fuel nozzle tip. You will model the heat transfer contribution of the fuel flow by an advective boundary condition. The geometry and boundary conditions for the problem are shown below The interior surface of the nozzle across which the fuel flows must be coupled to the fuel flow with a heat transfer coefficient. Since the corresponding fluid sink will not be a single node but a series of nodes the usual Loads/BCs Create/Convection/Template, Convection form does not apply.

Figure 1 Geometry 5.0” .5” Nickel (MID = 243) 0.05”

Steel (MID = 379) 0.1”

Still Air at h = K/L = 7.0 BTU/hr ft2 °F

Boundary Conditions Forced Convection Air T = 1000°F h = 500 BTU/hr ft2 °F

Radiation from Flame Flame Temp = 4000°F ε = 0.8 Fuel In

Internal Radiation e = 0.80 h

Specific gravity = 0.78 Tin = 200 °F h = 500.0 BTU/hr ft2 °F m = 50 lbm/hr Cp = 0.57 BTU/lbm °F

MSC.Patran 312 Exercise Workbook - Release 2001

17-3

Exercise Overview:

17-4

■

Create a new database named exercise_17.db. Set Tolerance to Default, and the Analysis Code to MSC/THERMAL.

■

Create the nozzle, fluid stream, and Convective Quad geometry.

■

Verify that surface normals are consistent with RxZ reversing any surface normals which are not consistent with RxZ.

■

Mesh the model surfaces with an IsoMesh of Quad4 elements and the curve representing the fluid stream with Bar2 elements, global edge length of 0.100.

■

Use Finite Elements/Create/Node/Edit to create two ambient nodes 998 and 999 for the ambient and flame temperatures, respectively.

■

Equivalence the nodes at the mating surface edges.

■

Apply Thermal Axisymmetric element properties to the nozzle and Advection Bar element properties to the flow stream.

■

Define three fixed temperature, three convective, and two radiative boundary condition in Loads/BC’s.

■

Create and post a group name Nozzle which only includes the nozzle elements.

■

Prepare and submit the model for analysis specifying that it is steady state analysis including viewfactor and radiation resistor computations, for an axisymmetric model with unit conversions from inches to feet that all calculations and output should be in oF.

■

Read and plot the results.

■

Quit MSC.Patran.

MSC.Patran 312 Exercise Workbook - Release 2001

Analysis of a Fuel Nozzle Tip Using Convection Between Regions

WORKSHOP 17

Exercise Procedure: 1.

Open a new database named exercise_17.db.

Within your window environment change directories to a convenient working directory. Run MSC.Patran by typing p3 in your xterm window.

Open a new database

Next, select File from the Menu Bar and select New… from the drop-down menu. Assign the name exercise_17.db to the new database by clicking in the New Database Name box and entering exercise_17 Select OK to create the new database File New... New Database Name

exercise_17

OK MSC/PATRAN will open a Viewport and change various Control Panel selections from a ghosted appearance to a bold format. When the New Model Preferences form appears on your screen, set the Tolerance to Default, and the Analysis Code to MSC/THERMAL. Select OK to close the New Model Preferences form. Tolerance

◆ Default

Analysis Code

MSC/THERMAL

OK 2.

Create the nozzle, fluid stream, and Convective Quad geometry.

Select the Geometry Applications radio button. Create the first of two surfaces that represent the geometry of the outer nozzle shell using the following Action, Object, and Method.

Create the nozzle and fluid stream geometry

◆ Geometry Create/Surface/XYZ Auto Execute



Vector Coordinates List



Origin Coordinates List

[0 0.2 0]

Apply MSC.Patran 312 Exercise Workbook - Release 2001

17-5

Create the nozzle and fluid stream geometry

Use Tool Bar Show Labels icon to turn on labels.

To create the second surface change the Vector Coordinates List to . Click in the Origin Coordinates List and select Point 4 (the lower right corner of Surface 1).

◆ Geometry Create/Surface/XYZ Vector Coordinates List



Origin Coordinates List



Apply

Select Viewing/Scale Factors... to increase the scale of the model in the Ydirection. This will expand the model display to facilitate viewing, picking, and displaying results. Only the model display is scaled not the actual model dimensions. Scaling may throw the coordinate system symbol out of the display viewport. Viewing Scale Factors... Model Y

5.0

Apply Cancel

17-6

MSC.Patran 312 Exercise Workbook - Release 2001

Analysis of a Fuel Nozzle Tip Using Convection Between Regions

WORKSHOP 17

The resulting model is shown below.

2

3 1

5 2

1

4

6

To create the surfaces that will represent the geometry where the Steel and Still Air will reside set the Geometry form Action, Object, and Method to Transform/Surface/Translate. Click in the Translator Vector databox and then choose the following Tip and base points icon.

Click on Point 5 and Point 6 to define the translation vector. Next, set the Repeat Count to 2, click in the Surface List databox and drag a rectangle around Surface 1 and Surface 2 in the viewport.

◆ Geometry Transform/Surface/Translate Translation Vector



Repeat Count

2

Auto Execute Surface List



Apply MSC.Patran 312 Exercise Workbook - Release 2001

17-7

Create the nozzle and fluid stream geometry

The resulting model is shown below.

2 1 7

3 1 3 5

10

4 8 11

5 2 4 6

6 9 12

The flow of fuel within the nozzle will be modelled with advection bars. Create the two curves where the bars will be placed. Change the Action, Object, and Method to Create/Curve/XYZ. For the first curve set the Vector and Origin Coordinates List to, and [0 0 0] respectively.

◆ Geometry Create/Curve/XYZ Vector Coordinates List Auto Execute Origin Coordinates List

[0 0 0]

Apply To create the second curve set the Vector and Origin Coordinates List to and Point 14 respectively. Vector Coordinates List



Origin Coordinates List



Apply

17-8

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 17

Analysis of a Fuel Nozzle Tip Using Convection Between Regions

Now, delete Surface 3 in the air gap.

◆ Geometry Delete/Any Geometric Entity List



Apply Refrest the graphics.

The resulting model is shown below.

MSC.Patran 312 Exercise Workbook - Release 2001

17-9

Verify surface normals and flow direction

3.

Verify surface normals and flow

Verify that surface normals are consistent with RxZ. Reverse any surface normals which are not consistent with RxZ.

Radiative boundary conditions modeled in an axisymmetric coordinate frame must have all element normals pointing in the RxZ (read R cross Z) direction. In this model, RxZ is in the global -Z direction. It is wise to verify the normal direction now since there are fewer surfaces than elements. This will facilitate viewing and reversing normals. Element normal will follow geometry normals in a 2D model. Alternatively, element normals can be reversed, if necessary, later in the modeling process. However, if LBC’s are applied to elements before the normals are reversed then when the element normals are reversed the LBC’s may be dropped from those elements and require review and reapplication. To verify normals change to an isometric view using the Tool Bar icon.

Use Show/Surface/Normal. Drag a rectangle around all surfaces. In this model all surfaces normals must be reversed. Use Edit/Surface/Reverse, select all the surfaces, Draw Normal Vectors to verify reversal.

◆ Geometry Show/Surface/Normal Surface List



Apply Edit/Surface/Reverse Auto Execute Surface List



Apply Draw Normal Vectors It is also prudent to verify the direction of the flow stream. Advection in an element flows in the local node 1 to node 2 direction. Unless reversed, the element local node 1/node 2 direction will follow the parent curve C1, or parametric, direction. Hence, it is sufficient to verify the C1 directions of Curve 1 and Curve 2. There is a toggle for displaying geometric parametric directions in Display/Geometry. Curves have only one parametric 17-10

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 17

Analysis of a Fuel Nozzle Tip Using Convection Between Regions

direction which is shown in the same color as the curve. Scaling may have offset the parametric marker from the curve but it’s color and relative length should facilitate identification. Display Geometry... Show Parametric Direction

Apply Cancel The resulting display is shown below.

Return to default Front view.

Remove parametric directions display. Display Geometry... MSC.Patran 312 Exercise Workbook - Release 2001

17-11

IsoMesh the surfaces and fluid stream curve

Show Parametric Direction

Apply Cancel Remove the Normal Vectors.

◆ Geometry Reset Graphics

IsoMesh the surfaces and fluid

4.

Mesh the model surfaces with an IsoMesh of Quad4 elements and the curve representing the fluid stream with Bar2 elements, global edge length of 0.100.

Select the Finite Elements Applications radio button. Set the Action, Object, and Type to Create/Mesh/Surface. Change the Global Edge Length to 0.100 and click in the Surface List box. Drag a rectangle around all surfaces in the viewport.

◆ Finite Elements Create/Mesh/Surface Global Edge Length

0.100

Surface List



Apply Create Bar2 elements along Curves 1 and 2.

◆ Finite Elements Create/Mesh/Curve Global Edge Length

0.100

Curve List



Apply

17-12

MSC.Patran 312 Exercise Workbook - Release 2001

Analysis of a Fuel Nozzle Tip Using Convection Between Regions

WORKSHOP 17

Create boundary nodes

5.

Use Finite Elements/Create/Node/Edit to create two ambient nodes 998 and 999 for the ambient and flame temperatures.

In the Finite Elements form create a boundary node which is not associated with geometry. The node is numbered 998. Locate the node at [2.5 0.3 0].

◆ Finite Elements Create/Node/Edit 998

Node ID List Associate with Geometry



Auto Execute

[2.5 0.3 0]

Node Location List

Apply Repeat for Node 999 located at [5.2 0.15 0]. Increase the display size of nodes. Use either Display/Finite Elements ... or the associated Tool Bar icon to change the node size. Display Finite Elements... Node Size

9

Apply Cancel or,

Select Display/Entity Color/Label/Render.../Hide All Entity Labels or use the Tool Bar Labels Hide icon to remove all labels and unclutter the display. Display Entity Color/Label/Render... Hide All Entity Labels Apply MSC.Patran 312 Exercise Workbook - Release 2001

17-13

Equivalence nodes

Cancel or,

The display should now appear as shown below.

Equivalen ce nodes

6.

Equivalence the nodes at the mating surface edges.

Using the Finite Elements form set the Action/Object/Method to Equivalence/All/Tolerance Cube and select Apply to eliminate duplicate nodes created at geometric entity edges.

◆ Finite Elements Equivalence/All/Tolerance Cube Apply 7.

Apply element properties to nozzle

17-14

Apply Thermal Axisymmetric element properties to the nozzle and Advection Bar element properties to the flow stream.

Use Tool Bar Label Control icon to turn on Surface labels. Close

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 17

Analysis of a Fuel Nozzle Tip Using Convection Between Regions

Select the Properties Applications radio button. Set the Action, Dimension, and Type to Create/2D/Thermal Axisymmetric. Enter Property Set Name Nickel. Select the Input Properties... box. Click in the Material Name box and enter 243. Select OK to close the form.Click in the Select Members box and select Surfaces 1, 2, and 4 in the viewport using the shift-left mouse button. Select Add then Apply in the Element Properties form to complete the element property definition.

◆ Properties Create/2D/Thermal Axisymmetric Property Set Name

Nickel

Input Properties... Material Name

243

OK Select Members



Add Apply

Repeat these steps for Steel, MID 379, on Surfaces 5 and 6.

The last element property you will create will define the Bar2 elements as advective bars. Change the Dimension to 1D and the Type to Advection Bar. Enter Adv_bars for the Property Set Name and then click on the Input Properties… button. When the Input Properties form appears enter 1 for the Cp-MPID and 50 for the Mass Flow Rate. Create/1D/Advection bar Property Set Name

Adv_bars

Input Properties... [Specific Heat MPID]

1

Mass Flow Rate

50

OK

MSC.Patran 312 Exercise Workbook - Release 2001

17-15

Apply boundary conditions



Select Members

Add Apply Though the Specific Heat MPID appears in square brackets it is, in fact, not an optional entry. Even in a steady state analysis advective conductors are derived from the product of specific heat and mass flow rate. 8.

Apply boundary conditions

Define three fixed temperature, three convective, and two radiative boundary condition in Loads/BC’s.

Select the Loads/BCs Applications radio button. Create a fixed 1000oF nodal boundary temperature named T_air. In the Input Data form define the fixed temperature. In the Select Region form pick Node 998, located above the nozzle model.

◆ Loads/BCs Create/Temperature/Nodal Option:

Fixed

New Set Name

T_air

Input Data... Fixed Temperature

1000.0

OK Select Application Region... Geometry Filter

◆ FEM

Select Nodes



Add OK Apply Repeat these steps for a New Set Name T_flame of 4000 oF applied to Node 999, located to the right of the nozzle and for a New Set Name T_fuel of 200oF applied to Node 221, located at the lower left corner of the model at the fuel stream inlet.

17-16

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 17

Analysis of a Fuel Nozzle Tip Using Convection Between Regions

Create the ambient convection boundary condition. Use a New Set Name Amb_conv, a Convection Coefficient of 500.0, and a Fluid Node 998.

◆ Loads/BCs Create/Convection/Element Uniform Options:

Template, Convection

New Set Name

Amb_conv

Target Element Type

2D

Input Data... Convection Coefficient

500

Fluid Node ID



OK Select Application Region... Geometry Filter

◆Geometry

Select Menu

Select an Edge icon

Select Surface or Edges



Add OK Apply Create gap condition across still air gap with h=k/L where k = 0.029 BTU/ hr ft2 °F and L = 0.05/12 ft. Hence h = 7.0 BTU/hr ft2 °F. .

◆ Loads/BCs Create/Convection/Element Uniform Option

Fixed Coefficient

New Set Name

Still_air

Target Element Type

2D MSC.Patran 312 Exercise Workbook - Release 2001

17-17

Apply boundary conditions

Region 2

2D

Input Data... Convection Coefficient

7.0

OK Select Application Region... Click in Application Region Select Surface or Edges



Add Click in Coupling Region Select Surface or Edges



Add OK Apply

Since the convection coefficient from fuel-to-nozzle is now constant, h=500BTU/hr ft2 °F, the Convection/Fixed Coefficient Regions option can also be used for the fuel-to-nozzle connection.

◆ Loads/BCs Create/Convection/Element Uniform Option

Fixed Coefficient

New Set Name

Fuel_convection

Target Element Type

2D

Region 2

1D

Input Data... Convection Coefficient

OK Select Application Region... Click in Application Region 17-18

MSC.Patran 312 Exercise Workbook - Release 2001

500.0

WORKSHOP 17

Analysis of a Fuel Nozzle Tip Using Convection Between Regions



Select Surface or Edges

Add Click in Coupling Region



Select Surface or Edges

Add OK Apply Create the flame radiation boundary condition. Use a New Set Name Flame_rad, a VFAC Template ID of 10, and an Ambient Node 999, a Convex Surface ID of 999, an Obstr Flag of 1, and an Enclosure ID of 1.

◆ Loads/BCs Create/Radiation/Element Uniform Option

Template, View Factor

New Set Name

Flame_rad

Target Element Type

2D

Input Data... Enclosure ID

1

VFAC Template ID

10

Convex Surface ID

999

Ambient Node ID



Can be obstructing surface

OK Select Application Region... Geometry Filter

◆Geometry

MSC.Patran 312 Exercise Workbook - Release 2001

17-19

Apply boundary conditions

Select Menu

Select an Edge icon

Select Surface or Edges



Add OK Apply Create the radiation effect in the still air gap.

◆ Loads/BCs Create/Radiation/Element Uniform Option

Template, View Factor

New Set Name

Still_air_rad

Target Element Type

2D

Input Data... Enclosure ID

2

VFAC Template ID

10

Convex Surface ID



Ambient Node ID



Can be obstructing surface



There are only 2 entries in this Input Data form. VFAC Template ID and Enclosure ID. OK Select Application Region...

17-20

Geometry Filter

◆Geometry

Select Surface or Edges



MSC.Patran 312 Exercise Workbook - Release 2001

Analysis of a Fuel Nozzle Tip Using Convection Between Regions

WORKSHOP 17

Add OK Apply With boundary conditions applied the model should now appear as shown below.

9.

Create and post a group name Nozzle which only includes the nozzle elements. You will create a group which will contain only entities associated with the nozzle.

Create a group maned nozzle

Group Create... New Group Name

Nozzle

Make Current



Unpost All Other Groups



MSC.Patran 312 Exercise Workbook - Release 2001

17-21

In unix create template.dat.apnd file

Entity Selections



Apply Cancel The model should now appear as shown below.

Reduce the node size with the Node Size icon.

In unix create template.d at.apnd file

10. Use the new Analysis/Build Template form to create a file named template.dat.apnd containing the VFAC definitions. Using Analysis/Build Template, create and edit the file template.dat.apnd in the directory which contains your database and where MSC.Patran is running. Create a definition VFAC for the flame radiation boundary condition. Shown below is the final form of the template.dat.apnd file created for this exercise. Note that any comment lines must be started with an * in column 1

17-22

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 17

Analysis of a Fuel Nozzle Tip Using Convection Between Regions

and make sure that there are no blank lines especially at the end of the file. Start typing from the first column and do no enter any blank lines.

◆ Analysis Build Template Create Template File... Create/VFAC/Data Entry VFAC ID

10

Emissivity

0.8

Apply Write File... OK Cancel Cancel VFAC 10 0 0.8 1 A mat.dat.apnd file is required to define the specific heat property of the advecture flow. The mat.dat.apnd file required for this exercise is identical to that created in Exercise 12. The final form of the mat.dat.apnd file is shown below for reference. MPID 1 C F 1.0 MDATA O.57 / 11. Prepare and submit the model for analysis specifying that it is steady state analysis including viewfactor and radiation resistor computations, for an axisymmetric model with unit conversions from inches to feet that all calculations and output should be in oF.

MSC.Patran 312 Exercise Workbook - Release 2001

Prepare and run analysis

17-23

Prepare and run analysis

Select the Analysis Applications radio button to prepare the analysis. Select the parameter forms reviewing and changing the settings as shown below. The analysis is submitted by selecting Apply in the Analysis form.

◆ Analysis Analyze/Full Model/Full Run Translation Parameters... Model Dimensionality

◆ Axisymmetric Geometry, R Z Co-ordinates

Radial, R Co-ordinate

◆ Yaxis ◆ Xaxis

Centerline, Z Co-ordinate

Perform Geometry Units Conversion From Units

inches

To Units

feet

File to Extract Undefined Materials:

3,mpidfph.bin (BTU-feet-lbmhour)

OK Solution Type... Perform Viewfactor Analysis

OK Solution Parameters... Calculation Temperature Scale

◆ Fahrenheit

Run Control Parameters... Stefan-Boltzmann Constant

1.7140E-9 BTU/HR/FT2/R4

Initial Temperature =

1000.0

Initial Temperature Scale

◆ Fahrenheit

OK OK Output Requests... Units Scale for Output Temperatures

◆ Fahrenheit

Units Definition for Time Label

Hours

OK 17-24

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 17

Analysis of a Fuel Nozzle Tip Using Convection Between Regions

Submit Options... Make sure both Create ViewFactor Control FIle (vf.ctl) and Execute Viewfactor Analysis are selected. OK Apply

12. Read and plot the results. From within MSC.Patran the only indication that the analysis has successfully finished is the existence of an nrX.nrf.01 results file in a subdirectory one level below your working directory.

Read and plot results

P3 was initiated from a working directory which contained the exercise_17.db database. Applying the analysis created a new subdirectory with the same name as the Job Name, exercise_17/. By using Read Result in the Analysis form and Selecting Results File... you can filter down to the Job Name subdirectory and check for the existence of a results file.

◆ Analysis Read Results/Result Entities Select Results File... Directories

/exercise_17

Filter Available Files

nr0.nrf.01

OK Select Rslt Template File... Files

pthermal_1_nodal.res_tmpl

OK Apply After results are read in plot the results. To plot the results use the Results Application radio button. Select you results file.

◆ Results MSC.Patran 312 Exercise Workbook - Release 2001

17-25

Quit MSC. Patran

Create/Quick Plot Select Result Cases

TIME: 0.0000000000D+00 S...

Select Fringe Result

Temperature,

Select the Fringe Attributes icon.

Display:

Element Edges

Label Style... Label Format:

Fixed

Significant figures

4

OK Apply The model should now appear as shown on the front panel of this exercise. 13. Quit MSC.Patran

Quit MSC. Patran

To stop MSC.Patran select File on the Menu Bar and select Quit from the drop-down menu.

17-26

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 18

Post-processing the Hybrid Microcircuit Results with Insight

Objective: ■

In this exercise you post-process the results of the hybrid microcircuit analysis using Insight tools.

MSC.Patran 312 Exercise Workbook - Release 2001

18-1

18-2

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 18

Post-processing the Hybrid Microcircuit

Model Description: In this exercise you will reopen the hybrid microcircuit database which now includes results data. You will use the Insight post-processing tools to enhance the presentation of the available results. Two isothermal surfaces will be generated which will provide a three dimensional view of the temperature field within the model. Also a series of planes will be created to expose the interior pattern of temperatures.

Exercise Overview: ■

Open the existing database named microcircuit.db.

■

Use Viewing/Named View Options... and Viewing/ Transformations... to change to an X-Z view.

■

With Display/Entity Color/Label/Render... change render style to hidden line and use Transformations... to readjust display to a better point of view for results.

■

Use Insight to create an Isosurface Tool with which to view isothermal surfaces contained within the model.

■

Use Insight to create a second Isosurface which will define 5 display planes through the model on which fringe results will be displayed.

■

Quit. MSC.Patran.

MSC.Patran 312 Exercise Workbook - Release 2001

18-3

Open an existing database

Exercise Procedure: 1.

Open an existing database

Open the existing database named microcircuit.db.

Within your window environment change directories to the microcircuit.db working directory. Run MSC.Patran by typing p3 in your xterm window. Next, select File from the Menu Bar and open the existing microcircuit database. File Open... Database List

microcircuit.db

OK MSC.Patran will open a Viewport and change various Main Form selections from a ghosted appearance to a bold format.

Change to an X-Z view

2.

Change the view to an X-Z view. (This step can also be accomplished simply by selecting the Tool Bar Bottom view icon).

Select Viewing from the Menu Bar to change to a default_view of the model hybrid_fem entities. Preferences Graphics... Auto Fit View

Apply Cancel Viewing Named View Options... Select Named View

default_view

Close

18-4

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 18

Post-processing the Hybrid Microcircuit

Select Viewing from the Menu Bar and use Transformations... to adjust the display to an X-Z view. When the rotation increment is defined use the -X rotation icon to complete the X-Z view. Viewing Transformations... Options... Rotation increment (deg)

90

◆ Screen Relative OK

Reset Graphics using the Reset Graphics icon.

The model should now appear as shown below.

MSC.Patran 312 Exercise Workbook - Release 2001

18-5

Change display point of view

3.

Change display point of

Change render style to hidden line and use Transformations... to adjust display to a better point of view for results.

Select Display/Entity Color/Label/Render... to Hidden Line to facilitate viewing. Display/Entity Color/Label/ Render... Render Style:

Hidden Line

Apply Cancel Or, use the Hidden Line icon.

Again use the Transformations form to change the view point. (The form should have been left open on the screen and should still be available. If necessary, reopen it using Viewing/ Transformations...).

Transformations

Viewing Transformations... Options... Rotation increment (deg)

15

◆ Screen Relative OK



OK

18-6

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 18

Post-processing the Hybrid Microcircuit

The display should now appear as shown below.

4.

Create an Isosurface Tool with which to view isothermal surfaces contained within the model.

Select the Insight Applications radio button. There will be a short delay while insight is loaded and the default_viewport is modified to show an ‘Insight Graphics Window’. Set Action/Tool to Create/Isosurface.

Create an Isosurfac e tool

◆ Insight Create/Isosurface Results Selection...

Select the results case and temperature data from the Results Selection form and select the Isovalue Setup... to define the number and value of the Isosurfaces. Current Load Case(s)

2.1-Time: 0.0000000000D+00 S...

Update Results Isosurface Result

1.1-Temperature,

Isovalue Setup... MSC.Patran 312 Exercise Workbook - Release 2001

18-7

Create an Isosurface tool

Using either the slider bar or by editing the entry box and hitting a change the Number of Isos to 2. Edit the Isovalue entry box and enter 23.0. Edit the Ending Value box and enter 26.0. Select OK twice to close the Result Isovalue Setup and Result Selection Form. Select Apply in the Insight Imaging form to create the Isos_1 Tool Number of Isos (Use Slider Bar)

2

Isovalue

23.0

Ending Value

26.0

OK OK Apply The Isos_1 tool will appear in the Existing Isosurfaces list, the Isosurface Name box will increment the Isosurface Tool Name, and two isotherms will be displayed in the viewport. The display should appear as shown below.

18-8

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 18

5.

Post-processing the Hybrid Microcircuit Create a second Isosurface Tool which will define 5 display planes through the model on which fringe results will be displayed.

To prepare the display for the second isosurface tool select Insight Control from the Menu Bar. Choose Post/Unpost Tools... Select None and Apply to clear the display.

Create another Isosurface tool and apply fringe

Insight Control Post/Unpost Tools... Select None Apply Cancel In the Insight Imaging form set Action/Tool to Create/Isosurface change the Isosurface Value from Result to Coord. Select Coordinate Selection and in the Isosurface Coordinate Selection using the slider bar or by editing the entry box and hitting increase the Number of Isos to 5. Set the Starting Value and Ending Value to 0.002 and 0.016, respectively. Select Isosurface Attributes to change the isosurface Color to white, Clip at Isosurface, and set display extremes to Free Edge. Select Apply to create the tool.

◆ Insight Create/Isosurface

◆ Coord.

Isosurface Value

Coordinate Selection... Number of Isos (Use Slider Bar)

5

Starting value

0.002

Ending Value

0.016

OK Isosurface Attributes... Color:

White

Clip at Isosurface < Display

Free Edge

> Display

Free Edge MSC.Patran 312 Exercise Workbook - Release 2001

18-9

Create another Isosurface tool and apply fringe data

OK Apply

The 5 isosurfaces should now be displayed as shown below.

This set of isosurface will be used to display results fringes. Use Create/ Fringe from the Insight Imaging form to create the Fringe Tool. Select the temperature results and Target the Isosurfaces defined in Isos_2.

◆ Insight Create/Fringe Results Selection... Current Load Case(s)

2.1-Time: 0.0000000000D+00 S...

Update Results Fringe Result

1.1-Temperature,

OK 18-10

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 18

Post-processing the Hybrid Microcircuit

Target

Isosurfaces

Target Isosurfaces

Isos_2

Apply The fringe results will be evaluated at the locations of the isosurface planes. The display should appear as shown below and on the front panel of this exercise.

6.

Quit MSC.Patran

To leave Insight deselect the Insight toggle.

Quit MSC.Patr

To stop MSC.Patran select File on the Menu Bar and select Quit from the drop-down menu.

MSC.Patran 312 Exercise Workbook - Release 2001

18-11

Quit MSC.Patran

18-12

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 19

Animating Results

Objective: ■

In this exercise you will post-process the time dependent results of Exercise 10 using Insight Tools and MSC.Patran results.

■

You will create an Insight animation of the transient heat transfer analysis.In this exercise you will postprocess the time dependent results of Exercise 10 using Insight Tools.

■

You will create animation using the MSC.Patran results application. MSC.Patran 312 Exercise Workbook - Release 2001

19-1

19-2

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 19

Animating Results

Model Description: In this exercise you will reopen the database developed in Exercise 10 which now includes time dependent results data. You will use the Insight postprocessing tools to enhance the presentation of the available results. A Fringe Tool will be created from the entire set of results. The results will then be animated using the Animation Control options within Insight Control.

Exercise Overview: ■

Open the existing database named exercise_10.db.

■

Use Insight to create a Fringe Tool with which to view a fringe plot of the results.

■

Use Insight Control/Range Control... to freeze the spectrum range in the ‘Insight Graphics Window’.

■

Use Insight Control/Animation Control... to Setup and control the animation in the ‘Insight Graphics Window’.

■

Exit Insight.

■

Use MSC.Patran Results application to animate the results.

■

Quit MSC.Patran.

Exercise Procedure: 1.

Open the existing database named exercise_10.db. . Within your window environment change directories to the microcircuit.db working directory. Run MSC.Patran by typing p3 in your xterm window.

Open an existing database

Next, select File from the Menu Bar and open the existing microcircuit database. File Open... Database List

exercise_10.db MSC.Patran 312 Exercise Workbook - Release 2001

19-3

Create an Insight Fringe tool

OK MSC.Patran will open a Viewport and change various Main Form selections from a ghosted appearance to a bold format.

If the display shows the Fringe Plot results from Exercise_10, clear the screen using the Reset Graphics icon.

The display should appear as shown below.

Create an Insight Fringe

19-4

2.

Use Insight to create a Fringe Tool with which to view a fringe plot of the results.

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 19

Animating Results

Select the Insight Applications radio button. There will be a short delay while insight is loaded and the default_viewport is modified to show an ‘Insight Graphics Window’. Set Action/Tool to Create/Fringe.

◆ Insight Create/Fringe Results Selection... Select all the results cases listed in the Current Load Case(s) list box and select Update Results. Select all the results files by depressing the left mouse button and dragging down through the list. Select Temperature data from the Fringe Result list box in the Results form. Be sure to select Temperature from the Fringe Result list box. It is selected when it is highlighted with a dark background.

Selection

Current Load Case(s)



Update Results Fringe Result

1.1-Temperature,

OK Apply

MSC.Patran 312 Exercise Workbook - Release 2001

19-5

Freeze the spectrum data range

The display should appear as shown below. It shows the fringe plot for the first results set at t=0.0s which is isothermal at 100oC.

3.

Freeze the spectrum data range

Use Insight Control/Range Control... to freeze the spectrum range in the Insight Graphics Window.

From the constraints applied to the analysis you know that all temperatures will remain between 100.0oC and 160.0oC. Taking advantage of this information we will freeze the spectrum range for all image frames created during the animation setup. Insight Control Range Control... Freeze Range Values Min.

100.0

Max.

160.0

Apply Cancel

19-6

MSC.Patran 312 Exercise Workbook - Release 2001

Animating Results

WORKSHOP 19

This step could also be performed at any time after the animation is created. If the temperature range is not known before hand, however, the initial animation may have a surprising appearance since each frame will auto range to the minimum and maximum temperature for that frame. Adjust the spectrum to range from blue/cold to white/hot.

Display Spectrums... Spectrum Type

◆ Temperature

Apply Cancel The display should appear as shown below.

4.

Use Insight Control/Animation Control... to Setup and control the animation in the Insight Graphics Window.

Insight Control MSC.Patran 312 Exercise Workbook - Release 2001

Setup and run the Insight animation 19-7

Setup and run the Insight animation

Animation Control... Setup... Non-Animation Tool(s)

FR-Fringe_1

Selecting the FR-Fringe_1 tool you created earlier initiates the Animation Attributes form. From this form we will define the Animation Type and Global Variable. Enable Animation Global Variable

TIME

Ok The Animation Attributes form will close. At this point define the number of frames, 13. This will create an animation frame for each 30s interval beginning at t=0s and ending at t=360s. The choice of number of frames is arbitrary and need not be identical to or a multiple of the number of results sets. Insight will interpolate on the Global Variable based on the result sets that are available. Hence, you could have chosen 25 frames for an animation frame at 15s intervals. In fact, this Animation is much better at 25 frames. Frames

13

Animate At this point Insight will build, in memory, each frame of the animation. Obviously choosing a greater number of frames to animate will result in increased frame processing time. The frames are built only once for a given animation setup and may optionally be saved to a file. This option was located on the Animation Setup form. As each frame is built you can observe the Time value change in the viewport. You can also assess Min and Max values, if necessary, to freeze the range at a later point. Once the animation begins the Animation Control form becomes available. On this form you may Pause/Stop Animation to adjust any of the features available. Toggling Pause/Stop Animation stops and starts the animation (frames are not rebuilt, they are already available). If your system is fast and your model is small some persistence may be required to pause or slow the animation. Use the slider to decrease Animation Speed. The Animation Speed slide is available even when an animation is playing.

19-8

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 19

Animating Results

Reduced Rendering will speed animation on slow systems or on animations with large amounts of results. However, it will produce only contour values. Cycle displays results for frames 1 through N repeatedly. Bounce displays results for frames 1 through N forwards and backwards repeatedly. Selecting Ok in the Animation Control form will create an Animation Tool from the setup and selections you’ve made. This tool will be available the next time you invoke Insight and you will not need to rebuild this animation; though, the frames will be reprocessed unless they were saved to a file in the Animation Setup form. OK

5.

Exit Insight.

To return to the standard set of Applications radio buttons and close Insight reselect the Insight Applications radio button in the Main Form at the top of the screen. Applications radio buttons are toggles which may be switched at any time.

Exit Insight

Answer Yes to the message requesting if the animation is to be cleared.

◆ Insight Do you wish to clear animation

6.

YES

Use MSC.Patran Results application to animate the results

Select MSC.Patran Results and use the various options to animate your results.

Use Results

◆ Results Create/Fringe Select Result Case(s):



Select Fringe Result:

Temperature,

MSC.Patran 312 Exercise Workbook - Release 2001

19-9

Quit MSC.Patran

Select the Fringe Attributes icon.

Display:

Element Edges

Label Style... Label Format:

Fixed

Significant figures

4

OK Spectrum... Current Selection:

hot cold 16

Apply Cancel Apply

(to create Fringe)

Create/Animation Plots to Animate:

None_FRI_default_Fringe

Animations Method:

Global Variable

Select Global Variable:

Time

Number of Frames:

25

Apply

7.

Quit MSC.Patr

Stop Animate. Quit MSC.Patran.

Stop Animation To stop MSC.Patran select File on the Menu Bar and select Quit from the drop-down menu.

19-10

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 20

SINDA Translation of a PWB Model

Objective: ■

Create a model by playing a session file.

■

Produce a run-ready SINDA/G deck from the model and post-process the SINDA/G temperature results.

MSC.Patran 312 Exercise Workbook - Release 2001

20-1

20-2

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 20

SINDA Translation of a PWB Model

Model Description: In this exercise you will read a session file which will construct a board level PWB (Printed Wiring Board) heat transfer model. When the session file ends it will have produced a model that is ready to analyze. You will run the analysis in MSC.Thermal but you will also produce a run-ready SINDA/G deck. Since the platform on which you work this exercise may not have a SINDA/ G executable module, results from SINDA/G are provided. With the possible exception of actually running the SINDA/G analysis, you will have used MSC.Patran to produce a syntactically correct SINDA/G deck and read in the resulting temperatures.

0.25 x 0.25 in h = 6.72 w/sq.in-C 4 typ bottom of PWB 0.5 in

2 in. 1 in

0.25 x 0.50 in. h = 3.36 w/sq. in-C 4 typ bottom of PWB

3 watts

2 in

6 in.

0.5 in .1 w

2 in

1 in.

.1 w

.1 w

0.25 in

Y 0.5 watts

.25 w 2 in

.25 w

.25 w

X 8 in. PWB is 0.125 in. thick kx = ky = 0.825 w/in-C kz = 0.04 w/in-C Tambient = 70 C

NOT TO SCALE

Figure 1

MSC.Patran 312 Exercise Workbook - Release 2001

20-3

Open a new database

Exercise Overview: ■

Create a new database named exercise_20.db. Set Tolerance to Default, and the Analysis Code to MSC/THERMAL.

■

Use File/Session/Play... to read exercise_20.ses file and create the analysis model of Figure 1.

■

Prepare and submit model for analysis selecting Submit Option/Create SINDA File (model.sin).

■

Modify the Select Results File... filter to retrieve nr0.sin.

■

Modify the Select Rslt Template File... filter to use the sinda.res_tmpl template.

■

Plot SINDA/G results.

■

Go to the Job Name subdirectory to review the contents of model.sin.01.

■

Quit MSC.Patran.

Exercise Procedure: Open a new database

1.

Open a new database named exercise_20.db.

Within your window environment change directories to a convenient working directory. Run MSC.Patran by typing p3 in your xterm window. Next, select File from the Top Menu Bar and select New… from the dropdown menu. Assign the name exercise_20.db to the new database by clicking in the New Database Name box and entering exercise_20. Select OK to create the new database File New... New Database Name

exercise_20

OK

20-4

MSC.Patran 312 Exercise Workbook - Release 2001

SINDA Translation of a PWB Model

WORKSHOP 20

MSC.Patran will open a Viewport and change various Control Panel selections from a ghosted appearance to a bold format. When the New Model Preferences form appears on your screen, set the Tolerance to Default, and the Analysis Code to MSC/THERMAL. Select OK to close the New Model Preferences form. Tolerance

◆ Default

Analysis Code

MSC/THERMAL

OK

2.

Use File/Session/Play... to read exercise_20.ses file and create the analysis model of Figure 1.

Read Session FIle

In order to guarantee that the model you crated will have the correct node ID’s in the proper sequence, you will create the model from a session file. Node sequence and location is important since the nr0.sin file identifies model temperatures with node IDs. The session file, once initiated, will run autonomously until the model is completed. File Sessions Play...



Play from File



Apply

Wait until the session file has completed the model. The Heartbeat will remain green and the Command Line History Window will indicate that “Session file stopped playing”

MSC.Patran 312 Exercise Workbook - Release 2001

20-5

Run Analysis

The model should appear as shown below.

3.

Run Analysis

Prepare and submit model for analysis.

Use the Tool Bar Node Size and Reset Graphics icon to reduce the size of the nodes and eliminate markers.

Go to the Analysis from to setup the analysis.

◆ Analysis Analyze/Full Model/Full Run Solution Parameters... Calculation Temperature Scale

◆ Celsius

OK Output Requests... Units Scale for Output Temperatures

◆ Celsius

OK Submit Options...

◆ Create SINDA Input File (model.sin)

OK Apply 20-6

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 20

4.

SINDA Translation of a PWB Model Modify the Select Results File... filter to retrieve nr0.sin.

Although the MSC.Thermal solver is also now solving this network a previous analysis was run on SINDA/G. The results are available in the file called nr0.sin.

Modify Result FIle Filter

In order to locate this SINDA/G model results file you must change the filter in the Select File form.

◆ Analysis Read Result/Result Entities Select Results FIle... Filter



Filter Directories



Available FIles



OK

5.

Modify the Select Rslt Template File... filter to use the sinda.res_tmpl template.

Select Rslt Template FIle... Filter

Modify Template FIle



Filter FIles



OK Apply

MSC.Patran 312 Exercise Workbook - Release 2001

20-7

Plot results

6.

Plot SINDA/G results.

Plot results To plot the results to posted FEM use the Results Application radio button.

◆ Results Create/Quick Plot Select Result Cases

P/THERMAL TRANSLATION,...

Select Fringe Result

Temperature,

Select the Fringe Attributes icon.

Display:

Element Edges

Label Style... Label Format:

Fixed

Significant figures

3

OK Apply At this point you may wish to read the MSC.Thermal results and compare them. Be sure to change the template file for the MSC.Thermal nr0.nrf.01 results set. 7.

Review Input Deck

Go to the Job Name subdirectory to review the contents of model.sin.01.

To view the SINDA/G input deck which was created, go to a UNIX shell and cd to the Job Name subdirectory, exercise_20. The input deck is the file model.sin.01 and can be viewed with any editor.

Quit MSC.Patr

20-8

8.

Quit MSC.Patran

To stop MSC.Patran select File on the Menu Bar and select Quit from the drop-down menu.

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 21

Optimizing Performance of Radiation Interchange Analysis

Objective: ■

Modify the database of exercise_14 and the template.dat.apnd file in order to increase analysis speed and reduce file size

■

Rerun and monitor the analysis and compare CPU time of the run and file size to those of Exercise 14

MSC.Patran 312 Exercise Workbook - Release 2001

21-1

21-2

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 21

Opt. Perf. of Radiation Interchange Analysis

Model Description: In this Exercise we will reopen the database created in Exercise 14 and modify some LBC’s and the template.dat.apnd file. These modifications will significantly reduce the execution time of both the radiation interchange calculations as well as the thermal analysis network run. Also, the size of several of the files will be significantly reduced. Any analyst who uses the radiation interchange capability of MSC.Thermal should become practiced in using the available flags and settings which will increase execution speed and reduce storage demands.

Exercise Overview: ■

Open the existing database named exercise_14.db.

■

Use LoadS/BCs/Modify/Radiation to modify the existing radiation boundary conditions.

■

Create a new radiation Load/BC for Surface 2.

■

Change the Job Name in the Analysis form to exercise_21.

■

Modify the template.dat.apnd file to include a collapse flag.

■

Submit the model for analysis and use the commands described to monitor its progress.

■

Debug, if necessary and resubmit after deleting all the files in the jobnamed subdirectory.

■

Read in results file and plot results.

■

Compare CPU times and File sizes.

■

Quit MSC.Patran.

MSC.Patran 312 Exercise Workbook - Release 2001

21-3

Open an existing database

Exercise Procedure: Open an existing database

1.

Open the existing database named exercise_14.db.

Within your window environment change directories to the microcircuit.db working directory. Run MSC.Patran by typing p3 in your xterm window. Next, select File from the Menu Bar and open the existing microcircuit database. File Open... Database List

exercise_14.db

OK MSC.Patran will open a Viewport and change various Control Panel selections from a ghosted appearance to a bold format.

Use Load/ BCs/Modify

2.

Use Loads/BCs/Modify/Radiation to modify the existing radiation boundary conditions.

In order to give a different Convex Surface ID flag to each surface it is necessary to modify the Input Data Form of the existing Load/BC for radiation.

◆ Loads/BCs Modify/Radiation Option:

Template, View Factor

Select Set to Modify



Modify Data... Convex Surface ID Can Be Obstructing Surface

1

OK Modify Application Region... Application Region

Surface 1 (delete Surface 2)

OK Apply

21-4

MSC.Patran 312 Exercise Workbook - Release 2001

Opt. Perf. of Radiation Interchange Analysis

WORKSHOP 21

3.

Create a new radiation Load/BC for Surface 2.

By limiting the application region of the previous Loads/BC to Surface 1, it is necessary to create a second Load/BC for Surface 2. Obviously the Application Region will be Surface 2. The Input Data Form will be the same as the last Load/BC but will have a different Convex Surface ID flag.

Create a new Load/ BC

◆ Loads/BCs Create/Radiation/Element Uniform New Set Name

Rad2

Target Element Type

2D

Input Data... Enclosure ID

1

Vfac Template ID

200

Convex Surface ID

2

Can Be Obstructing Surface

OK Select Application Region



Add OK Apply

4.

Change the Job Name in the Analysis form to exercise_21.

On the Analysis Form change the Job Name to exercise_21. This will create a new subdirectory of files for this analysis which will facilitate comparing data between the two runs, exercise_14 and exercise_21.

Change Job Name

◆ Analysis Job Name

exercise_21

MSC.Patran 312 Exercise Workbook - Release 2001

21-5

Modify template

5.

Modify template

Modify the template.dat.apnd file to include a collapse flag.

Use Analysis/Build Template to create a new template.dat.apnd file which includes a collapse flag entry. *============================ VFAC 100 0.1 1.0 0 0 0.0 0.0 0 100 VFAC 200 0.1 1.0 0 0 0.0 0.0 0 200 *============================ The main advantage of using COLLAPSE to collapse radiosity nodes is that this will result in a much smaller number of radiation resistors in the model. A smaller number of resistors usually means that the thermal analysis will proceed faster. In the best cases, the number of radiation resistors may be reduced by about a factor of four for 2D Cartesian or axisymmetric models and by about a factor of 16 for 3D models.

6.

Submit the model

Submit the model for analysis and use the commands described to monitor its progress.

Return to the open Analysis Form and check Apply. After the stops scrolling, change focus to the UNIX window and affect the cd exercise_21 command with a carriage return. Repeated execution of ls within the jobname subdirectory will show you the progress of your analysis: Once the file vf.msg.01 appears, type:

Command Line History Window

$ tail -f vf.msg.01 This will provide a continuous status of the viewfactor run. When viewfactor is complete it will end the status with a message, Successful Execution Completed. Use the c key combination to terminate the tail function. Again input a sequence of ls commands until a stat.bin file appears in the directory list. Once you the see the stat.bin file type: $ qstat c

21-6

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 21

Opt. Perf. of Radiation Interchange Analysis

to monitor the progress of the network analysis. This command will self terminate after 20 repetitions or upon job completion. Monitor the data from the qstat command to determine the numerical status of the analysis. Check for the existence of an nr0.nrf.01 results file. If it exists the numerical analysis is complete and successful.

7.

Debug

Debug, if necessary, and resubmit after deleting all the files in the jobnamed subdirectory.

If Step 5 does not yield a results file then determine what went wrong. Is there a patqb.log file? If so, then is there a patq.msg file? If there is no patqb.log file then look in the MSC.Patran Command Line History Window or in the MSC.Patran interface for any error messages. If there is a patqb.log file and no patq.msg file then look for error messages in patqb.log. If there is a patq.msg file then look for error messages in it. If there are no error messages in the patq.msg file but this analysis requests that a viewfactor run be made then is there a vf.msg file? If there is a vf.msg file then look for error messages in it. For this analysis answering the above questions should provide a clue to the problem. Once the error is found and resolved Repeat Steps 4 and 5. Remember that now many of the files will have an extension index which has been incremented by 1, e.g., vf.msg.01 to vf.msg.02. If it is convenient you may delete all the files from the exercise_21 Job Named subdirectory prior to resubmitting the analysis.

MSC.Patran 312 Exercise Workbook - Release 2001

21-7

Read and plot results

Read and plot results

8.

Read in results file and plot results.

From within MSC.Patran the only indication that the analysis has successfully finished is the existence of an nrX.nrf.01 results file in a subdirectory one level below your working directory. Recall that p3 was initiated from a working directory which contained the microcircuit.db database file. The analysis, initiated from within MSC.Patran, created a new subdirectory with the same name as the Job Name; it should be named exercise_21/. By using Read Result in the Analysis form and Selecting Results File... you can filter down to the Job Name subdirectory and check for the existence of the results file.

◆ Analysis Read Results/Result Entities Select Results File... Directories

/exercise_21

Filter Available Files

nr0.nrf.01

OK Select Rslt Template File... Files

pthermal_1_nodal.res_tmpl

OK Apply To plot the results to posted FEM use the Results Application radio button.

◆ Results Create/Quick Plot Select Result Cases

TIME: 0.0000000000D+00 S...

Select Fringe Result

Temperature,

Apply

21-8

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 21

Opt. Perf. of Radiation Interchange Analysis

Select the Fringe Attributes icon.

Display:

Element Edges

Label Style... Label Format:

Fixed

Significant figures

4

OK Apply 9.

Compare CPU times and File sizes.

Use the qstat command in each of the Job Name subdirectories to find the CPU Time data and record it in the following table.

Compare files

Use the ls -al v* command in each Job Name subdirectory to record the size of the vfnode.dat, vfraw.dat, and vfres.dat files in the following table. Subdirectories CPU Time

Exercise_14

Exercise_21

(sec.)

Vfnode.dat (bytes) Vfraw.dat (bytes) Vfres.dat (bytes)

The size and speed improvement are significant.

10. Quit MSC.Patran. To stop MSC.Patran select File on the Menu Bar and select Quit from the drop-down menu.

MSC.Patran 312 Exercise Workbook - Release 2001

Quit MSC.Patr

21-9

Quit MSC.Patran

21-10

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 22

Steady State Radiative Boundary Conditions

Objectives: ■

Create a 2D model that incorporates two enclosures.

■

Define separate radiative boundary conditions for gray body and wave length dependent radiation within the enclosures.

■

Perform the Steady State thermal analysis and post process the analysis results with MSC.Patran’s Result and Insight tools.

MSC.Patran 312 Exercise Workbook - Release 2001

22-1

22-2

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 22

Model Description: In this exercise you will construct a model with two separate radiation enclosures, one for gray body radiation and the other for wave length dependent radiation. No material (e.g. air) will be defined in the enclosure therefore only Radiation heat transfer can transfer heat energy across the enclosures. In the enclosure where it is assumed that the surfaces are gray the emissivity will be constant regardless of the surface temperatures. The other enclosure will incorporate wave length dependent radiation which is a significant extension of the gray body theory. Normal radiosity is divided into discrete frequency bands with emissivity and transmissivity assumed to be constant within these frequency bands. o

1500 C (fixed)

0.3

0.5

0.4

0.5

0.3

Iron E-1

1.6

E-2

0.6

0.5

2.0 Node 1000 o T=200 C (fixed)

o

0 C (fixed) Enclosure Emissivity Information: ε = 0.9

Enclosure 1

Gray

Enclosure 2

For: 0.0 ≤ λ ≤ 5.0 ε(λ)=0.9 τ=0.4 5.0 < λ ≤ ∞ ε(λ)=0.2 τ=0.4

MSC.Patran 312 Exercise Workbook - Release 2001

22-3

Open a new database

Exercise Overview: ■

Create a new database named exercise_22.db. Set Tolerance to Default, and the Analysis Code to MSC/THERMAL.

■

Create a plate geometry.

■

Mesh the surface with an IsoMesh of quad4 elements, global edge length of 0.16666.

■

Equivalence nodes to eliminate duplicate nodes and eliminate “cracks” in the mesh.

■

Create a fixed temperature boundary nodes.

■

Apply Temperature boundary conditions.

■

Apply View Factor boundary conditions.

■

Define the Element Properties for the models Iron material.

■

Prepare and submit the model for analysis.

■

Read and plot the results.

■

Create Temperature and Insight Contours.

■

Quit MSC.Patran.

Exercise Procedure: 1.

Open a new database named exercise_22.db.

Within your window environment change directories to a convenient working directory. Run MSC.Patran by typing p3 in your xterm window. Next, select File from the Top Menu Bar and select New… from the dropdown menu. Assign the name exercise_23.db to the new database by clicking in the New Database Name box and entering exercise_22. Select OK to create the new database. File New... New Database Name

exercise_22

OK

22-4

MSC.Patran 312 Exercise Workbook - Release 2001

Open a new database

WORKSHOP 22

MSC.Patran will open a Viewport and change various Control Panel selections from a ghosted appearance to a bold format. When the New Model Preferences form appears on your screen, set the Tolerance to Default, and the Analysis Code to MSC/THERMAL. Select OK to close the New Model Preferences form. Tolerance

◆ Default

Analysis Code

MSC/THERMAL

OK

Create plate geometry

2.

Create a plate geometry.

Select the Geometry Applications Radio Button. Create a surface using the following Action, Object, and Method. Click in the appropriate list boxes to edit the default values and change them to values listed below. First, turn on the labels using the Tool Bar Show Labels icon.

◆ Geometry Create/Surface/XYZ

Vector Coordinate List Auto Execute (deselect)

Apply Vector Coordinate List



Origin Coordinates List

Point 4

Apply Vector Coordinate List



Origin Coordinates List

Point 6

Apply Transform/Surface/Mirror Define Mirror Plane Normal

Coord 0.1

Offset Parameters

1.0 MSC.Patran 312 Exercise Workbook - Release 2001

22-5

Create plate geometry

Surface List

Surface 1:2

Apply Define Mirror Plane Normal

Coord 0.2

Offset Parameters

0.8

Surface List

Surface 1:5

Apply Create/Surface/Curve Starting Curve list

Surface 1.2

Ending Curve List

Surface 6.3

Apply Starting Curve list

Surface 3.2

Ending Curve List

Surface 8.3

Apply Starting Curve list

Surface 9.2

Ending Curve List

Surface 4.3

Apply Since this is a 2D model using radiation, check surface normal to verify that they are all in the +Z direction. Change to Iso 1 view using the Tool Bar Iso 1 View icon.

◆ Geometry Show/Surface/Normal Surface List



Apply

22-6

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 22

If there are any surface that is pointing the -Z direction, change them with the following steps. Edit/Surface/Reverse Surface List



Apply The resulting model is shown below.

MSC.Patran 312 Exercise Workbook - Release 2001

22-7

IsoMesh the surfaces

3.

IsoMesh the surfaces

Mesh the surface with an IsoMesh of quad4 elements, global edge length of 0.16666.

Select the Finite Elements Applications Radio Button. Set the Action, Object, and Type to Create/Mesh/Surface. Change the Global Edge Length to 0.16666 and select Surface 1 for inclusion in the Surface List.

◆ Finite Elements Create/Mesh/Surface Global Edge Length

0.16666

Surface List



Apply Return to the Front View using the Tool Bar Front View icon and turn off the labels with the Hide Labels icon.

The display should now appear as shown below.

22-8

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 22

Equivalen ce mesh nodes

4.

Equivalence nodes to eliminate duplicate nodes and eliminate “cracks” in the mesh.

Set the Action, Object, and Method to Equivalence/All/Tolerance Cube. Select Apply to complete the function. The nodes bounding the interior cracks will be circled in the display and the will indicate that a number of nodes are deleted.

Command Line

Reexamine the mesh boundaries after equivalencies with Verify/Element/ Boundaries to verify the free edges.

Create a boundary nodes

5.

Create a fixed temperature boundary nodes.

Select the Finite Elements Applications radio button. Create a node which is not associated with geometry. The node is numbered 1000.

◆ Finite Elements Create/Node/Edit 1000

Node ID List Associate with Geometry

[1.365 0.836 0.00]

Node Location List

Apply Increase the node size by using the Tool Bar Node Size icon.

Apply temperatu re boundary

6.

Apply Temperature boundary conditions.

First, create a node that will represent the Participating Medium temperature.

◆ Loads/BCs Create/Temperature/Nodal Option:

Fixed

New Set Name

Temp_Part_Med

Input Data... MSC.Patran 312 Exercise Workbook - Release 2001

22-9

Apply temperature boundary conditions

Fixed Temperature

200

OK Select Application Region...

◆ FEM Select Node

Node 1000

Add OK Apply Next, assign fixed temperatures of 1500°C and 0°C respectively to the top and bottom geometry edges of the model. Use T_top and T_bottom for their respective New Set Names. New Set Name

T_top

Input Data... Fixed Temperature

1500

OK Select Application Region...

◆ Geometry Select Geometry Entities/Select Menu



Select Geometry Entities



Add OK Apply New Set Name

T_bottom

Input Data... Fixed Temperature

0

OK Select Application Region...

22-10

MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 22



Select Geometry Entities

Add OK Apply

Apply View Factor boundary

7.

Apply View Factor boundary conditions.

To create the view factor boundary conditions for the two enclosures you will first supply geometric information in the P3/PATRAN Loads/BCs form and then enter data concerning the Emissivity and Transmissivity values in the template.dat.apnd using the new Analysis/Build Template form. In the Load/Boundary Conditions form, change the Action, Object, and Type option menus respectively to Create/Radiation/Element Uniform. Change the Target Element Type to 2D.

◆ Loads/BCs Create/Radiation/Element Uniform Option:

Template, View Factors

New Set Name

Encl_101

Target Element Type:

2D

Input Data... Enclosure ID

1

VFAC Template ID

100

OK Select Application Region...

◆ Geometry Select Surfaces or Edges /Select Menu



MSC.Patran 312 Exercise Workbook - Release 2001

22-11

Apply View Factor boundary conditions



Select Surfaces or Edges

Add OK Apply Encl_201

New Set Name

Input Data... Enclosure ID

2

Vfac Template ID

200

Participating Media Node ID