Expertfea Com Catalog June 2014
April 12, 2017 | Author: Prakash Kancharla | Category: N/A
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Download Expertfea Com Catalog June 2014...
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expertfea.com expertfea.com catalog with 21 FEA tutorials available in June 2014
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Finite Element Analysis Hints and Ansys Workbench Tutorial
Static Structural FEA of meshing spur gears 2
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CONTENT:
1. Introduction....................................................................... page 3 2. Advice and good practices for a future FEA engineer......... page 4 3. What we learn in this tutorial.............................................. page 16 4. Static Structural FEA of meshing spur gears...................... page 17 5. The end............................................................................. page 29
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3. What we learn in this tutorial
- how to define and edit non-linear Contacts - how to define and edit Joints - how to define the Mesh - how to define proper Output (including basic Fatigue Tool) - how to read the Solver
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4. Static Structural FEA of meshing spur gears
1. Open Ansys Workbench; drag Static Structural into the Project Schematic area
2. Right click Geometry, Replace Geometry, Browse for 2013_05_14_gears2_asm.STEP, OK
3. Right click on the gear on the left and Rename it to "gear +Z"; Rename the other gear " gear - Z" 5
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1. In Solution Output, select Time Increment to see its values, getting a hint on the trend of the solving process; after a bisection, these values will suddenly decrease
2. Check the values for the Contact Pressure as seen here; click on Probe than on the desired spots on the needed surfaces in contact
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Finite Element Analysis Hints and Ansys Workbench Tutorial
Static Structural FEA of a sphere pressing with plasticity onto a plate (double symmetry) 7
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CONTENT:
1. Introduction.................................................................... page 3 2. Advice and good practices for a future FEA engineer...... page 4 3. What we learn in this tutorial........................................... page 16 4. Static Structural FEA of sphere-plate plasticity............... page 17 5. The end.......................................................................... page 45
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3. What we learn in this tutorial
- how to define Materials - how to define and edit Contacts - how to create the Mesh - how to insert Supports - how to define Symmetry Regions - how to define proper Output - how to read the Solver
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4. Static Structural FEA of sphere-plate plasticity
1. Open Ansys Workbench; drag the geometry file from your computer into the Project Schematic area
2. Drag the Static Structural analysis on the Geometry tab and release it will share its geometry file 3. Your Static Structural analysis should look like this 10
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1. Double click Model in Static Structural and the Mechanical window will open like here
2. Expand the Geometry tree and rename the parts with more relevant names
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1. The default contact is Bonded; we will select for Contact face the spherical face (green here), than hit Apply
2. For Target face we will select the flat face of the plate (green here), than hit Apply
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1. We will let Ansys WB create the mesh automatically by right clicking on Mesh, Generate Mesh
2. The Default mesh should look like this; we will modify the parameters later, on the next, more advanced tutorials; for now it is helpful to account for the small number of nodes and elements, which means less time consumed with solving 13
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1. During solving, click on Solution Information, Solution output, Solver output to see what the solver is doing; these messages will be important later, when we will need to improve or debug more complex analyses 2. Change from Solver Output to Force Convergence to see a graphical plot of how the solution will converge; as seen in the Legend, the Force Convergence curve should intersect with the Force Criterion curve in order to achieve convergence
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1. In this case, for faster solving time, you can press Stop Solution than click on Analysis Settings, Solver Controls, Solver Type and change from Program Controlled to Direct, then hit Solve again
2. Because the steps can become very crowded, you can "rarify them" by in 25 Display Points
3. This is how the analysis looks at the end of the solving time; the messages are not to worry in this case 15
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1. This is the Equivalent Stress plot
2. This is the vertical Directional Deformation plot
3. To see the elements, we can press Show Elements on this top bar 16
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1. This is the Equivalent Stress plot where we can see the element edges
2. Plasticity means that we should have remanent deformations; we can clearly see this only if we apply the load than release it, to see if the plate comes to its initial shape; to do this, on Analysis Settings we change in Step Controls the Number of Steps to 4
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1. The Prescribed Displacement was initially -2 mm
2. We insert these values to apply than release the load that the quarter sphere exerts on the plate
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1. During solving time, we can change the Solution Output to Time Increment to see how the solver automatically adjusts the time steps to achieve convergence
2. The solved analysis should look like here when it reaches time step 4 19
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1. Looking for the Stress plot, we can see that, after the sphere has risen to its initial position, the plate remains deformed; we can animate the results by clicking the play button
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Finite Element Analysis Hints and Ansys Workbench Tutorial
Static Structural FEA of meshing bevel gears (debugging solution to achieve convergence) 21
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CONTENT:
1. Introduction.................................................................... page 3 2. Advice and good practices for a future FEA engineer...... page 4 3. What we learn in this tutorial........................................... page 16 4. Static Structural FEA of meshing bevel gears.................. page 17 5. The end........................................................................... page 51
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3. What we learn in this tutorial
- how to work with Contacts - how to work with Joints, parameterize the Joints - how to create, simplify and refine the Mesh, parameterize the Mesh - how to simplify the 3D model in Ansys Workbench Geometry module - how to define proper Solution output, parameterize the output - how to debug the Solution if it does not converge, apply suitable measures to achieve convergence - how to use the parameters in defining Design Points, run multiple consecutive scenarios without interfering in Ansys Workbench
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4. FEA of a Static Structural case of meshing bevel gears
1. Open Ansys Workbench; drag Static Structural into the Project Schematic area
2. Right click Geometry, Replace Geometry, Browse for Bevel Gear T24-T16-M3.IGS, OK
3. Right click on the gear highlighted in green and Rename it to "big_gear"; Rename the other gear " small_gear"
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1. To find out the expected life-time of the small gear, on Fatigue Tool we will select Life for the small gear; notice the fatigue criteria Ansys uses by default
2. Right click on Contact Tool, Insert, Gap
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1. For computation, right click on Solution, Solve
2. When the solution is running, this is how Solver Output looks like, obtaining a realtime log with the solver's processes
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1. Being an important solver parameter, you can see the Time Increment as here
2. Extending the mesh refinement leads to convergence on several steps; to rarify the seen steps, select Solution Information, Display Points: 25 27
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1. We still have no convergence; it is time to refine once more the gears, but because the number of nodes and elements is high, let us cut the model on the regions not FEA relevant: on their centers
2. We go to Project Schematic, right click on Geometry, Edit Geometry 28
3. To import the gears, right click on Import1, Generate
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1. Select this face of the small gear and click on New Sketch button
2. To have a view normal to sketch, select the Look at Face/Plane/Sketch button; instead Modeling, go to Sketching tab, select Circle and snap to the center of the small gear
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1. To cut the material on the big gear, select the details seen here, than right click on Extrude2, Generate
2. We will suppress the resulting cut cylinders; Ctrl select the last 2 solids, right click, Suppress Solid Bodies 30
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1. Re-run the analysis with high hopes this time :)
2. Our hopes were met, because the analysis successfully converged!
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1. This is how the stress looks at the last time step; notice the peaks caused by the teeth collisions
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1. This is how the gaps in contact look like
2. To easily make multiple consecutive runs, we can change the parameters values for the items we chose before; go to Project Schematic, right click on Parameter Set, Edit
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Finite Element Analysis Hints and Ansys Workbench Tutorial
Explicit Dynamics FEA of a car body crashing into a wall and a wedge 34
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CONTENT:
1. Introduction.................................................................... page 3 2. Advice and good practices for a future FEA engineer...... page 4 3. What we learn in this tutorial........................................... page 16 4. Explicit Dyanmics FEA of a car body crashing................. page 17 5. The end.......................................................................... page 46
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3. What we learn in this tutorial
- how to work with Dynamics, analyses that occur in time - how to use Symmetry conditions for 3D bodies - how to refine the Mesh or make it coarse, parameterize the mesh - how to define proper Solution output and re-define it, parameterize the output - how to duplicate and re-use analyses - how to use the parameters in defining Design Points, run multiple consecutive scenarios without interfering in Ansys Workbench
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4. Explicit Dyanmics FEA of a car body crashing
Wall-Carbody FEA
1. Open Ansys Workbench; drag Explicit Dynamics into the Project Schematic
2. Right click Geometry, Replace Geometry, Browse for carbody_wall.STEP, Open
3. Open Mechanical window, and selecting the bodies in the tree we see that only the highlighted ones are relevant for our analysis 37
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1. Right click on the highlighted unnecessary bodies and suppress them
2. Select the last surface body and insert 0.3 mm for the Thickness; tick the Thickness box to parameterize it for later usage
3. To achieve deformations past the Yield Point of the material, change it to nonlinear: Assignment, Import 38
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1. We can see that the mesh is with TET elements on the wall (as we requested before) and quadrilateral elements on the carbody; also, for Explicit Dynamics, the number of nodes and elements is too high, leading to 6-10 hours of solving time
2. Click on Mesh and make Sizing, Smoothing, Low; right click on Mesh, Update 3. Now the number of nodes and elements is 2.5 times smaller, which will lead to less than 30 min solving time
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1. Clicking on Solution Information, Solution Output , Energy Conservation will give us this windows; even though the amount of work done fluctuates, it is most important for the Energy Error not to increase (the default is set to 10%=0.1), or else will lead to stopping the solving
2. Clicking on Solution Information, Solution Output , Energy Summary will give us this window; it is most important for the Hourglass Energy not to increase, as seen here 40 © expertfea.com fea.com expert
1. As the solving continues, we can see that the fluctuations of Work Done subside, which is a very good sign and the value for Energy Error is constant and low
2. Also, we can see that the fluctuations of the Kinetic Energy subside, which is a very good sign and there is no sign of the Hourglass Energy 41
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1. After ~24 min of solving, the solution is done, as seen here
2. Here is the Displacement plot of the wall: ~500mm as we imposed
3. Here we see the overall Stress plot, with some high values given by the coarse mesh we used in the wall; let us scope only the carbody to see its stress plot 42
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1. To realize the second analysis, with the carbody colliding with a wedge block, right click on Explicit Dynamics, Duplicate
Carbody-Wedge FEA
2. Both analyses should look like here; rename the items as seen here, for better visualization
3. Right click Geometry, Replace Geometry, Browse for carbody_wedge.STEP, Open
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1. This is the stress plot for the carbody, with a maximum on the impact region; let us parameterize Maximum Value Over Time, Maximum
2. This is the displacement plot for the front of the carbody; the value is true, because if the carbody travels with 50 m/s, than in 0.02 s it will travel with 1 m/s; let us parameterize it by ticking on Maximum Value Over Time, Minimum 44
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Finite Element Analysis Hints and Ansys Workbench Tutorial
Static Structural FEA of a copper sheet stamping (double symmetry) 45
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CONTENT:
1. Introduction.................................................................... page 3 2. Advice and good practices for a future FEA engineer...... page 4 3. What we learn in this tutorial........................................... page 16 4. Static Structural FEA of a copper sheet stamping.......... page 17 5. The end.......................................................................... page 54
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3. What we learn in this tutorial
- how to assign non-linear materials - how to use Symmetry conditions on 2 axes for 3D bodies - how to properly assign different elements and refine the Mesh - how to edit the geometry in Ansys Workbench - how to define complex Analysis Settings and stabilize the solving - how to define proper Solution output; how to investigate the output of the Contacts (Pressure, Status, Stress etc.)
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4. Static Structural FEA of a copper sheet stamping (double symmetry)
1. This is the geometry setup in Solidworks, before it was simplified, for easier meshing and solving time
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1. We have cut half of the assembly longitudinally and transversally
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1. Open Ansys Workbench; drag Static Structural into the Project Schematic area
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2. Right click Geometry, Import Geometry, Browse for narrow_stamp.x_t, Open
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1. In Mechanical it will open the 3D model ready for pre-processing
2. Let us change the material of the plate to a nonlinear one. After we rename the parts as here, click on plate, Material, Assignment, Import 51
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1. Create also a Symmetry Region for the die faces, as seen here in green
2. After having finished defining the symmetry conditions for X axis, you can rename them, than select all 3 Symmetry Regions to check if they are properly defined, as seen here in red 52
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1. Select the plate, Apply than choose Method, Tetrahedrons
2. Let us refine the mesh on the multiple rounds of the die; right click on Mesh, Sizing, select the rounds shown green here, Element Size 0.1 mm, Apply 53
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1. Click on Model, Show All Bodies; let us refine the surface mesh of the underside of the plate seen here in green: right click on Mesh, Sizing, 1 mm, Apply
2. Because we need to round the outer edge of the plate, we will go to project Schematic window, right click on Geometry, Edit Geometry
3. In the DesignModeler window, to import the geometry, right click on Import1, Generate 54
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1. We will insert a downwards displacement on the punch: right click on Static Structural, Insert, Displacement, Apply
2. We select from the punch these 3 faces in green
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1. To find out the stress in all bodies: right click on Solution, Insert, Stress, Equivalent von-Mises
2. To find out the stress only in the plate, let us duplicate the previous one: right click on Equivalent Stress, Duplicate
3. With Body filter pressed, select the plate than Apply 56
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1. To find out how much plasticity we will have in the plate, right click on Solution, Insert, Strain, Equivalent Plastic
2. We will scope only the plate, Apply
3. To find out how the contacts behave, right click on Solution, Insert, Contact Tool, Contact Tool 57
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1. We are interested in the Contact Pressure: click on Status and change Type to Pressure
2. Before solving this analysis, let us see the Mesh: right click on it, Generate Mesh
3. The mesh should look like here; right click on Solution, Solve 58
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1. The Directional Deformation on Z axis looks like this
2. The Stress in all bodies looks like this
3. The Stress only in the plate looks like this
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Finite Element Analysis Hints and Ansys Workbench Tutorial
Static Structural FEA of rolling of a copper plate 60
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CONTENT:
1. Introduction.................................................................... page 3 2. Advice and good practices for a future FEA engineer...... page 4 3. What we learn in this tutorial........................................... page 16 4. Static Structural FEA of rolling of a copper plate............ page 17 5. The end.......................................................................... page 51
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2. Advice and good practices for a future FEA engineer a) Where do I find info and docs? b) Where do I find 3D models for FEA practice? c) Where do I find databases with materials? d) What should I know about the meshing procedures? e) How can I validate my FEA results/analyses? f) Advice for future eastern and mid-eastern FEA engineers. g) What should I do to become an FEA expert, with strong knowledge and experience?
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3. What we learn in this tutorial
- how to assign non-linear materials - how to edit the geometry in Ansys Workbench - how to resize the Mesh - how to define Joints - how to define complex Contacts - how to define complex Analysis Settings and stabilize the solving - how to define proper Solution output: Force and Moment Reactions, Contact Pressure, Plastic Strain etc.
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4. Static Structural FEA of rolling of a copper plate
1. Start a Static Structural analysis, right click on Geometry and Insert 2013_07_21_rolling.stp
2. Because the plate is too wide and too short, we will optimize it: Right click on Geometry, Edit Geometry in Design Modeler
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1. This is how to initial geometry looks in Design Modeler
2. With Selection filter on Faces (Ctrl+F), click on one of the lateral sides of the plate
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1. To look normally at the sketch, press Look At Face/Plane/Sketch
2. Select Sketching tab and press Rectangle
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1. Draw a free-style rectangle that will contain the plate
2. Return to Modeling tab than click Extrude
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1. To extend the plate, select its end, than click New Sketch
2. Look at Face / Plane; switch to Sketching tab, Modify
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1. Press Duplicate and select the lines of the rectangle
2. Right click, Duplicate Selection
3. Back to Modeling tab, press Extrude
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1. The new Extrude should have these details
2. Having obtained the optimized geometry, Close Design Modeler
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1. Back to Project Schematic, right click on Model, Edit
2. Mechanical window will show us this initial setup; right click on the parts, Rename, if you are more into English
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1. To assign the material to the piece, select it and go to Import
2. Select the first Bonded contact, click on Target and select both external faces of the wheel, Apply 72
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1. Select the first Bonded contact, click on Contact and select all 3 underside faces that will touch the Target, Apply
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1. Solution, Strain, Equivalent Plastic
2. To see the values only in the piece, select it, Apply
3. Solution, Stress, Equivalent (von-Mises)
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1. Solution, Probe, Force Reaction
2. Solution Output, Force Convergence will give a similar plot; some bisections can be seen because the high plasticity that appears due to increased thickness of the piece
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1. Solution Output, Time Increment will show how the solver automatically varies the time steps, in order to achieve convergence; usually, the time increments decrease after a bisection, trying to rise again
2. Right click on Directional Deformation, Clear Generated Data
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1. Select the faces on the tip of the piece, Apply
2. Right click on Directional Deformation, Evaluate All Results
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1. The result makes more sense now, showing clearly that the front of the piece advanced with ~85mm
2. The Equivalent Plastic Strain looks like this; because copper alloys generally break at 30 %, the values we obtained are for a thicker than normal plate; to avoid these high strains, in a factory, the thinning is done in multiple stages / passes
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1. Very interesting would be to find out the lateral deformation of the piece, how much its width is increased due to rolling? Solution, Directional Deformation, select both lateral faces, Orientation, Z Axis, Apply
2. Right click on Directional Deformation 2, Evaluate All Results
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1. The Directional Deformation of piece on Z axis look like here, showing clearly that each face widened with ~7.8 mm; congratulations, you have successfully finished this nice FEA tutorial!
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Finite Element Analysis Hints and Ansys Workbench Tutorial
Transient Structural FEA of heat generated between a piston and a cylinder 81
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CONTENT:
1. Introduction.................................................................... page 3 2. Advice and good practices for a future FEA engineer...... page 4 3. What we learn in this tutorial........................................... page 16 4. Transient Structural FEA of heat generated between a piston and a cylinder...................................................... page 17 5. The end.......................................................................... page 57
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3. What we learn in this tutorial
- how to simplify a complex model - how to assign a complex Contact - how to insert Joints, with the ground and between bodies - how to resize the Mesh - how to prescribe APDL commands - how to define complex Analysis Settings and stabilize the solving - how to define proper Solution output: User Defined Result (Temperature), Force Reaction, Contact Pressure, Plastic Strain, Velocity etc.
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4. Transient Structural FEA of heat generated between a piston and a cylinder
1. Start a Transient Structural analysis, right click on Geometry, Import Geometry, Browse: piston2_tutorial7.x_t
2. Right click on Model, Refresh, than Edit...
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1. When Mechanical window opens, this is how the imported model looks like; we will simplify it for faster solving time
2. Select with Ctrl pressed the shown parts, right click, Suppress Body
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1. With the unnecessary parts removed, we should see this from under the cylinder 2. Go to Connections, Contacts and observe that the contacts for the suppressed parts automatically became suppressed; select the only valid contact, right click on it than Rename Based on Definition
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1. Select the hole on the crank, seen here in green, than go to Reference, Scope, Apply
2. Select the corresponding hole on the connecting rod, seen here in green, than go to Mobile, Scope, Apply 87
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1. With the selection filter on Body, select the piston, Apply, Orientation, Y Axis
2. Solution, Deformation, Directional Velocity
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1. Again, we select only the piston, as we did before: select the piston, Apply, Orientation, Y Axis
2. Solution, Stress, Equivalent (von Mises)
3. Solution, Contact Tool 89
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1. For Contact Tool, because the default is Status, change Type to Pressure
2. Solution, Probe, Joint
3. Boundary Condition, Revolute - ConnectingRod; To PistonHead;
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1. This is the vertical displacement of the piston, with a sinusoidal shape, as we would expect it
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1. This is the Temperature plot inside the cylinder
2. This is the Temperature plot outside the piston
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Finite Element Analysis Hints and Ansys Workbench Tutorial
Modal analysis and random vibrations using PSD on a PCB
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CONTENT:
1. Introduction.................................................................... page 3 2. Advice and good practices for a future FEA engineer...... page 4 3. What we learn in this tutorial........................................... page 16 4. Modal analysis and random vibrations using PSD on a PCB........................................................ page 17 5. The end.......................................................................... page 63
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3. What we learn in this tutorial
- how to assign new materials - how to edit the Contacts - how to define a Modal analysis and ask for natural frequencies - how to understand an interpret Random vibration analyses - how to define Random vibrations analyses on all 3 axes - how to check the strength of parts using Equivalent Stress and Response PSD results etc.
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4. Modal analysis and random vibrations using PSD on a PCB
1. Drag a Modal analysis in Project Schematic window, right click on Geometry, Import Geometry, Browse: 2013_07_26_PCB.step
2. Double click on Model and the Mechanical window will open showing the imported geometry; we can see some support bushings underneath the PCB 96
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1. We will remove these bushings: select with Ctrl pressed all 4 bushings, right click, Suppress Body
2. Because it's not default in Ansys library, we will create the material for the PCB, which is a layered epoxy composite called FR4; select the last part, Material, New material 97
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1. Having the materials that we need, click Refresh Project, Return to Project
2. Back to mechanical window, select with Shift pressed, from the tree all the parts, green intense here, except the last one (the PCB), Material, Assignment, Aluminum Alloy
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1. No interference now
2. This is the 2nd mode
3. This is the 3rd mode
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1. This is the 4th mode
2. This is the 5th mode
3. This is the 10th mode
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As a reminder, we will quote the basics of Random analysis from: http://www.sharcnet.ca/Software/Fluent13/help/wb_sim/ds_spectral_analysis_type.html
Random Vibration Analysis Introduction This analysis enables you to determine the response of structures to vibration loads that are random in nature. An example would be the response of a sensitive electronic component mounted in a car subjected to the vibration from the engine, pavement roughness, and acoustic pressure. Loads such as the acceleration caused by the pavement roughness are not deterministic, that is, the time history of the load is unique every time the car runs over the same stretch of road. Hence it is not possible to predict precisely the value of the load at a point in its time history. Such load histories, however, can be characterized statistically (mean, root mean square, standard deviation). Also random loads are non-periodic and contain a multitude of frequencies. The frequency content of the time history (spectrum) is captured along with the statistics and used as the load in the random vibration analysis. This spectrum, for historical reasons, is called Power Spectral Density or PSD. In a random vibration analysis since the input excitations are statistical in nature, so are the output responses such as displacements, stresses, and so on. Typical applications include aerospace and electronic packaging components subject to engine vibration, turbulence and acoustic pressures, tall buildings under wind load, structures subject to earthquakes, and ocean wave loading on offshore structures.
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1. In Project Schematic, drag Random Vibration to the Solution of our Modal analysis, than drop 2. The result should look like this
3. Opening the Mechanical window we see that Ansys "forgets" the Modal solution, so we need to Solve it again
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1. Right click, Clear Generated Data
2. Having active the Body selection filter, click the capacitors, green here, Apply
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1. Because we let 1 Sigma for the Scale Factor, in 68.269% of the time, the stress will be under this value shown here; nevertheless, the stress values exceeds the Ultimate Tensile Stress for Aluminum alloys, meaning that these legs will break under the imposed PSD for X axis
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1. The Response PSD plot looks like here; close Mechanical window
2. Drag Random Vibration on Modal Solution; name it Random Vibration Z axis 105
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1. To obtain plots for Y axis with Response PSD vs. PSD G Acceleration, select them both with Ctrl pressed and click New Chart and Table; Rename to Chart Z axis
2. This is the resulting chart, with overimposed values for both curves; notice that we obtain peaks in Response PSD at the first and second natural frequencies, which are 228.3 and 500.98 Hz (see Total Deformations in Modal analysis)
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Finite Element Analysis Hints and Ansys Workbench Tutorial
Static Structural FEA of a roller bearing under load 107
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CONTENT:
1. Introduction.................................................................... page 3 2. Advice and good practices for a future FEA engineer...... page 4 3. What we learn in this tutorial........................................... page 16 4. Static Structural FEA of a roller bearing under load......... page 17 5. The end.......................................................................... page 41
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3. What we learn in this tutorial
- to define complex multiple Contacts - to define multiple Joints - to modify the Mesh to suit analysis' needs - to define proper Analysis Settings and stabilize the solving - to define proper output for forces, moments, rotations, contact behavior etc.
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4. Static Structural FEA of a roller bearing under load
1. Drag a Static Structural analysis in Project Schematic window, right click on Geometry, Import Geometry, Browse: 2013_08_01_roller_bearing1.x_t
2. After import, right click Model, Edit...
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1. To ignore the roller cage, in Mechanical window, right click on cage;CirPattern1, Suppress Body
2. Right click on Contacts, Delete
3. Right click on Contacts, Insert, manual Contact Region 111
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1. Right click on Contacts, Insert, Joint
2. Connection Type, Body-Ground
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1. Select the outer face of the bearing, green, here, Mobile, Scope, Apply
2. From Connections toolbar, select BodyGround, Revolute
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1. Select the inner face of the bearing, green here, Mobile, Scope, Apply
2. Drag a window as shown here, to include all bodies
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1. Method, Tetrahedrons
2. Right click on Mesh, Insert, Sizing
3. Select the inner and outer faces of the bearing, green here, Apply, Element Size = 35 mm 115
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1. This is the Stress plot
2. This is the Contact Status plot
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1. This is the Joint Probe showing Total Moment
2. This is the Joint Probe showing the Relative Rotation; feel free to modify the friction coefficient, the rotational velocity and the bearing load and compare the results; congratulations, you have successfully finished this nice FEA
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Finite Element Analysis Hints and Ansys Workbench Tutorial
EXPLICIT DYNAMICS FEA OF MACHINING WITH A PLANER 118
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CONTENT:
1. Introduction.................................................................... page 3 2. Advice and good practices for a future FEA engineer...... page 4 3. What we learn in this tutorial........................................... page 16 4. Explicit Dynamics FEA of machining with a planer........... page 17 5. The end........................................................................... page 30
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3. What we learn in this tutorial
- to assign Explicit Materials - to define various body loads - to mesh in a simplified manner, for faster solving time - to define proper Analysis Settings for split second event - to define proper output for velocity, stress, strain etc. - to interpret the behavior of the solver
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To take into account our new materials, exit by clicking Refresh project, than Return to Project
Back to project Schematic, right click on Geometry, Import Geometry, Browse for 2013_09_11_machining3.x_t
As an easier reminder, you can rename the Geometry: right click, Rename to 2013_09_11_machining3.x_t
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Let us define the preprocessing conditions: right click on Model, Edit...
In Mechanical window, right click on first body from the tree, Rename it to "piece"
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After Apply, select Type, Number of Divisions, 10
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Go to Analysis Settings and insert End Time, 0.00075 From Environment toolbar select Velocity
To define the needed output, select Solution, Deformation, Directional
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Solution, Total Velocity
Solution, Stress, Equivalent (von-Mises)
Solution, Strain, Equivalent Plastic
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Select only the piece, green here, Apply
Preparing of the model is done, let us proceed to the solving stage: right click on Solution, Solve
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If you click immediately on Solution Information you will see how a log with a presolver setup, as shown here
If you click on Solver Output you will see that, initially, Ansys Workbench predicts that the analysis will be done in 9.9 minutes; but this is done prior having the collision and the large deformations
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Click on Solution Output, Time Increment, we see that it fluctuated initially, but it's stabilized afterwards
As we said, the solver was wrong to assume 9.9 minutes of solving and, after collision is established, we see that it takes almost double
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This is the Total Velocity plot
This is the Stress plot
This is the Strain plot only in piece. Congratulations, you have successfully finished this simple Explicit Dynamics analysis!
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Finite Element Analysis Hints and Ansys Workbench Tutorial
STATIC STRUCTURAL FEA OF A THREADED BOLTBOLT-WASHERWASHER-NUT CONNECTION 130
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CONTENT:
1. Introduction.................................................................... page 3 2. Advice and good practices for a future FEA engineer...... page 4 3. What we learn in this tutorial........................................... page 16 4. Static Structural FEA of a threaded bolt-washer-nut connection......................................................................... page 17 5. The end........................................................................... page 54
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3. What we learn in this tutorial
- to assign solvable Contacts, and Joints that mimic the real load - to mesh in a simplified manner, for faster solving time - to define proper Analysis Settings and stabilize the solving - to define proper output for deformation, stress, strain, reactions etc. - to customize the solver's response - to create full and section views for better handling and result probing
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4. Static Structural FEA of a threaded bolt-washer-nut connection
Drag and drop Static Structural from left column called Analysis Systems; right click on Geometry, Import Geometry, Browse: 2013_09_30_bolt_washer4.x_t
After the import is done, right click on Model, Edit...
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This is the 3D model; for easier handling, right click on each part from the Model tree, Rename: washer (than nut, than bolt) as seen here
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With Ctrl key pressed, click Scope, Target, 4 Faces and deselect the top and the bottom of the thread
The result should look like this; Apply
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From tree click on Solution, than go to the upper toolbar, Deformation, Total Deformation, Directional
With selection filter on Body, click the bolt, Apply
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Solution, Stress, Equivalent (von-Mises)
Scope only the washer, Apply
Right click on the previously created Equivalent Stress, Duplicate
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Scope only the bolt, Apply
Solution, Strain, Equivalent (von-Mises)
Scope only the nut, Apply
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To proceed to the solving part, right click on Solution, Solve
Firstly, the mesh is created and this is how it looks like
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Clicking Solver Output gives this solver log
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To obtain an easier readable graphical representation of this log, select Solution Output, Force Convergence
This is how the Force Convergence plot looks like; observe that the analysis performs well, the bisections being expected due to the high contact forces
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As the solving continues, the spikes may get pretty crowded, as seen here
This is the Directional Deformation plot in bolt and washer
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This is the Stress plot in washer; the extremely high values appear because we exaggerated with the pressing of the bolt and the materials we used do not suffer plasticity; assign non-linear materials to all parts, re-solve and see the difference
This is the contact Pressure for the Frictional contact
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Finite Element Analysis Hints and Ansys Workbench Tutorial
EXPLICIT DYNAMICS FEA OF THE IMPACT BETWEEN A BOWLING BALL AND ITS PINS 144
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CONTENT:
1. Introduction.................................................................... page 3 2. Advice and good practices for a future FEA engineer...... page 4 3. What we learn in this tutorial........................................... page 16 4. Explicit Dynamics FEA of the impact between a bowling ball and its pins............................................................................... page 17 5. The end........................................................................... page 53
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3. What we learn in this tutorial
- to edit the 3D model to obtain shell elements - to mesh in a simplified manner, for faster solving time - to define proper Analysis Settings correlated with the nodes and elements number - to define proper output for deformation, stress, velocity etc. - to properly observe the solver's response - to parameterize the input data for automatic solving of multiple FEA scenarios in the same file
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4. Explicit Dynamics FEA of the impact between a bowling ball and its pins
Drag and drop Explicit Dynamics from left column called Analysis Systems; right click on Geometry, Import Geometry, Browse: 2013_10_01_bowling1.x_t
Right click on Geometry, Edit Geometry in DesignModeler
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In DesignModeler window, right click on Import1, Generate
This is the result of the import: the walls are solid and we will make them thin, to have shell elements
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In the main window, right click Model, Edit...
This is how the geometry looks like; because we have question mark in front of Geometry, we need to define the thickness of the surfaces/shells we crated in DesignModeler
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Select the last 2 parts and assign them 5mm thickness (the lateral walls were united into one surface)
With the Face filter active, click the ball, Apply
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For the ball to run into the pins, select X Component, Tabular
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This is the Energy Conservation plot before any collision
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For easier reading, insert 100 Display Points (instead of 0) and we will obtain a better resolution
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This is the Total Deformation plot in all bodies; ~8 meters is the height that a pin reached because it fell off the "bowling alley" and is headed to the abyss
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This is the Directional Velocity plot on X axis for the ball; its fluctuation can be seen in the bottom graph
If, for instance, you need the investigate the trajectory of any Deformation plot 155 pin, you can create a Directional © expertfea.com expertfea.com (vertical here), select the pin, Apply
Right click on the newly created Directional Deformation, Evaluate All Results
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The needed variation in time, of the pin's height, looks like here
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Let us parameterize the extreme values for later solving; check the boxes in front, as seen here marked with blue P letters
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To find out if we will have other parts that will eventually fall into the abyss, let us parameterize the maximum displacement, as seen here
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Finite Element Analysis Hints and Ansys Workbench Tutorial
STATIC STRUCTURAL FEA OF STAMPING WITH HALF SYMMETRY 160
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CONTENT:
1. Introduction.................................................................... page 3 2. Advice and good practices for a future FEA engineer...... page 4 3. What we learn in this tutorial........................................... page 16 4. Static Structural FEA of stamping with half symmetry..... page 17 5. The end........................................................................... page 52
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3. What we learn in this tutorial
- to assign non-linear materials - to simplify the 3D model and apply symmetries - to assign complex contacts suitable to large strains - to define proper Analysis Settings to ensure smooth solving - to define proper output for stress, strain, tools, probes etc. - to properly observe the solver's response - to re-evaluate the output data according to most important steps
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4. Static Structural FEA of stamping with half symmetry First, make sure that you have a proper geometry, like the one we provide, shown here
Drag and drop Static Structural from left column called Analysis Systems; to insert the material for the copper plate, right click 163 © expertfea.com expertfea.com on Engineering Data, Edit...
Once the model is imported, select XYPlane, than press New Sketch button, as seen here
To normally look at the sketch, press Look at Face/Plane/Sketch button
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If at first the zoom level doesn't reveal the entire model, use Box zoom and drag several windows with it in the center of the coordinate system we see
Box zoom several times in the center, as seen here
Then the model starts to appear; repeat the zooming
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When we have this magnitude of zoom, we can stop zooming
Select the cut surface of the die (green here, Apply)
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Observe that our symmetries are as default, about X axis which is normal to the cut surfaces, red axis here
Right click on Connections, Contacts, Rename based on Definition
Select with Ctrl pressed both contacts, Flip Contact/Target
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With Ctrl pressed, click the lateral surface to unselect it (blue here), than click the spherical surface, (green here); Apply
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This is how the Target part of the first contact should look like (green here); right click anywhere, Show All Bodies
Select the touching surfaces, Apply, Element Size = 1
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This is the result
Environment, Fixed Support
Select the outer faces of the die (green here), Apply 170
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With selection filter on Body, select the piece (green here, Apply)
Solution, Tools, Contact Tool
Uncheck the second contact, to have this result
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Select Status and replace with Pressure, as seen here
It's very useful to hit Interrupt Solution after some solving was done, to check if the analysis performs as desired; notice the Pause symbol near Solution, which means that the analysis can be continued 172
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This is the max. pressure plot in first Contact Tool
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For Contact Tool 2, retrieve also the value from second 6
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The Reaction Force plot gives us the value required to stamp the sheetmetal; max. value at second 6, where we have the max. depth of the punch; congratulations, you have successfully finished this nice FEA!
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Finite Element Analysis Hints and Ansys Workbench Tutorial
Seismic Random Vibration analysis using PSD on a real size skyscraper 176
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CONTENT:
1. Introduction.................................................................... page 3 2. Advice and good practices for a future FEA engineer...... page 4 3. What we learn in this tutorial........................................... page 16 4. Seismic Random Vibration analysis using PSD on a real size skyscraper......................................................................... page 17 5. The end.......................................................................... page 68
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3. What we learn in this tutorial
- how to assign new materials - how to manage only important parts - how to define a Modal analysis and ask for natural frequencies - how to understand and interpret Random Vibration analyses - how to define Random Vibrations analyses on all 3 axes - how to check the strength of parts using Equivalent Stress and Response PSD results etc.
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4. Seismic Random Vibration analysis using PSD on a real size skyscraper
Drag a Modal analysis in Project Schematic window, right click on Engineering Data, Edit...
Click the button Engineering Data Sources to reveal all material libraries
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From General Materials tab, choose Concrete by clicking the yellow plus sign
For the new material to be taken into account by Ansys, click Refresh Project, Return to Project
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Right click on Mesh, Insert, Sizing
With selection filter on Body, click the 6 columns (green here), Geometry, Apply
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Assign them Element Size, 1000 mm
To see the mesh, right click on it, Generate Mesh
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After the solving is finished, here is the Total Deformation plot for the 1st vibration mode; the magnitude of the deformation is not realistic in any modal analysis, only the tendency of the deformation is; most important here are the natural frequencies found by FEA
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This is the Total Deformation plot for the 5th vibration mode
Because we have finished with the Modal analysis, which is the basis of every vibration simulation, Let us leave this window; File, Close Mechanical
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Back to project Schematic, drag and drop Random Vibration from the left toolbox onto the Solution of the Modal analysis
Right click on Equivalent Stress, Duplicate
Select only the concrete part, Apply
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Solution, Probe, Response PSD
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Once the analysis is solved, let us change the orientation to Y Axis, which is the vertical one
Right click on Directional Deformation, Evaluate All Results
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Finite Element Analysis Hints and Ansys Workbench Tutorial
STATIC STRUCTURAL FEA OF A TOGGLE CLAMP WITH PLASTICITY
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CONTENT:
1. Introduction.................................................................... page 3 2. Advice and good practices for a future FEA engineer...... page 4 3. What we learn in this tutorial........................................... page 16 4. Static Structural FEA of toggle clamp with plasticity....... page 17 5. The end........................................................................... page 47
3. What we learn in this tutorial 189 © expertfea.com expertfea.com
- to assign non-linear materials, that allow plasticity - to properly mesh the contacts - to assign many types of Joints - to define proper Analysis Settings to stabilize the solving - to define proper output for stress, strain, tools, probes etc.
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4. Static Structural FEA of toggle clamp with plasticity
Firstly, make sure that you have a proper geometry, like the one we provide, shown here
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Select Contacts, right click, Rename Based on Definition; select each contact and look at the mating parts; we will suppress the contacrts that are not of interest in this FEA
Select the shown contacts with Ctrl pressed, right click, Suppress
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Select 4th contact, which is very important; observe that it is incomplete, because it does not contain all the surfaces that will later touch the handle, red here
Click Contact, 3 Faces and, with Ctrl pressed add these 3 surfaces, green here, to obtain 6 faces for the Contact, Apply 193 © expertfea.com expertfea.com
Select both bolt holes, Scope, Apply
Connections, Body-Ground, Fixed, select the underside of the base plate, Scope, Apply 194
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Connections, Body-Body, Revolute
Select the outer surface, green here, Reference Scope, Apply
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Selecting Static Structural will activate the Environment upper toolbar; Loads, Joint
Select the first Revolute joint
Insert these Details; observe that the arrow shows a proper rotation
Insert these values in the table 196
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Select Directional Deformation, than click on the surface of the washer that touches the spring, green here, Apply
Select the Coordinate System we just created
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Solution, Strain, Equivalent Total
With selection filter on Body, select this green part, Apply
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If at Solution Output you choose Force Convergence you will see this window
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After 10-15 minutes, the analysis is solved; this is the Total Deformation plot
This is the Directional Deformation plot, where we see the washer (hence this side of the spring), which is displaced with ~34 mm
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This is the Equivalent Total Strain plot
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Finite Element Analysis Hints and Ansys Workbench Tutorial
TRANSIENT STRUCTURAL FEA OF BENDING A LAMELLA WITH PLASTICITY AND SPRING BACK EFFECT
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CONTENT:
1. Introduction.................................................................... page 3 2. Advice and good practices for a future FEA engineer...... page 4 3. What we learn in this tutorial........................................... page 16 4. Transient Structural FEA of bending a lamella with plasticity and spring back effect....................................................... page 17 5. The end........................................................................... page 48
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3. What we learn in this tutorial
- to assign non-linear materials, that allow plasticity and spring back - to properly mesh the contacts - to assign many types of restraints, to achieve convergence - to define proper Analysis Settings to stabilize the solving - to define proper output for stress, strain, tools, probes and results depending on time
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4. Transient Structural FEA of bending a lamella with plasticity and spring back effect
Firstly, make sure that you have a proper geometry, like the one we provide, shown here
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Drag Transient Structural from Toolbox. To allow plasticity in the parts, let us define the non-linear material: right click Engineering Data, Edit... Back to Project Schematic, right click on Geometry, Import Geometry, Browse... "2013_11_13_bending_lamella1.x_t"
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Right click on Model, Edit...
This is the 3D model; if you like English names, let us change the default ones; right click each part, Rename and assign different names
Rename the parts as here
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The mesh looks like here, with an optimum number of nodes and elements, to ensure short solving time
Analysis Settings, Number of Steps = 30
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Select the external faces of the die, green here, Apply
Right click Transient (A5), Insert, Displacement
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Select all lateral faces, green here, Apply; Z Component = 0 mm
Solution, Deformation, Directional
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With selection filter on Body, click the punch and the lamella, Apply; orientation, Y Axis
With selection filter on Face, click the top face of the lamella, Apply; orientation, Y Axis
Solution, Stress, Equivalent (von-Mises)
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With selection filter on Body, click the lamella, Apply
Solution, Strain, Equivalent Total; with selection filter on Body, click the lamella, Apply
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Making Display Points = 35 will give you a rarified plot, with last 35 substeps/increments
After ~1 hour solving time, the analysis is done; this is the Total Deformation plot in all parts
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This is the Directional Deformation plot on Y axis, vertically; observe a remanent deformation of 0.626 mm, due to the spring back effect
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This is the Directional Deformation plot on Y axis, vertically, on the upper face of the lamella; the spring back effect is seen more clear on both green and red line, in the lower Graph tab
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Finite Element Analysis Hints and Ansys Workbench Tutorial
TRANSIENT STRUCTURAL FEA OF A GRIPPER WITH GEARS AND JAWS
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CONTENT:
1. Introduction.................................................................... page 3 2. Advice and good practices for a future FEA engineer...... page 4 3. What we learn in this tutorial........................................... page 16 4. Transient Structural FEA of a gripper with gears and jaws.................................................................................... page 17 5. The end........................................................................... page 50
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3. What we learn in this tutorial
- to take advantage of rigid bodies - to properly set-up the contacts in moving gears - to assign many types of joints (12 different ones) - to define proper Analysis Settings to stabilize the solving - to define proper output for stress, strain, tools, lots of probes and results depending on time
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4. Transient Structural FEA of a gripper with gears and jaws
Firstly, make sure that you have a proper geometry, like the one we provide, shown here
Double click Transient Structural from Toolbox. Right click Geometry, Import Geometry, Browse... "2013_12_08_claw_gears1.x_t"
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Right click Model, Edit...
With Shift or Ctrl pressed, select all the parts named "ClawBolt1", right click, Suppress
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For easier handling, right click on the active parts and Rename them as seen here
Select first 3 parts, green here, and make their Stiffness Behavior, Rigid
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Right click on Contacts, Rename Based on Definition
With Shift pressed select all contacts, than with Ctrl unselect the ones marked with green check (as seen here), right click on the inactive selected contacts, Suppress
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Properly suppressed, the unnecessary contacts receive an X sign in front
As an exercise, do a similar Revolute Joint for the other gear, transparent here
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For Reference, Scope, select this cylindrical surface of the Housing plate, green here, Apply
For Mobile, Scope, select the corresponding surface of the Link, green here, Apply
Connections, Body-Body, Revolute
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For Reference, Scope, select this cylindrical surface of the Jaw, green here, Apply
For Mobile, Scope, select the corresponding surface of the Link, green here, Apply
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This is the resulting Spring joint
For verification, select with Shift pressed all 12 joints and they should look like here
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Solution, Deformation, Directional
Right click anywhere, Show All Bodies; Orientation, Z Axis, select with Ctrl pressed these green surfaces, Apply
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Solution, Tools, Contact Tool
Right click Status, Duplicate
Change Status 2's Type to Pressure
Solution, Probe, Force Reaction
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Insert these details
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Click on Solution Information to see what the solver is doing
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For a graphical representation of the solver's activity, change Solver Output to Force Convergence; for a rarified plot, make Display Points = 35
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After ~25 min, the solve is finished; this is the Total Deformation plot
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This is the Strain plot
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This is the Stress plot
This is the Directional Deformation plot showing the displacement/ the stroke of the jaws
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Finite Element Analysis Hints and Ansys Workbench Tutorial
TRANSIENT STRUCTURAL FEA OF A MISALIGNED 4-CYLINDER ENGINE
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CONTENT:
1. Introduction.................................................................... page 3 2. Advice and good practices for a future FEA engineer...... page 4 3. What we learn in this tutorial........................................... page 16 4. Transient Structural FEA of a misaligned 4-cylinder engine................................................................................ page 17 5. The end........................................................................... page 56
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3. What we learn in this tutorial
- to properly set-up the contacts in moving parts - to pre-investigate the contact behavior, for a proper definition - to assign many types of joints (14 different ones) - to define proper Analysis Settings to stabilize the solving - to define proper output for stress, strain, tools, lots of probes and results depending on time
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4. Transient Structural FEA of a misaligned 4-cylinder engine
Firstly, make sure that you have a proper geometry, like the one we provide, shown here
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Double click Transient Structural from Toolbox. Right click Geometry, Import Geometry, Browse... " 2013_12_09_engine1.x_t"
Right click Model, Edit...
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In Mechanical window, expand Connections and right click on Contacts, Rename Based on Definition
To check for interferences in contact areas, right click on Contact Tool, Insert, Penetration
Right click, Generate Initial Contact Results
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Initial Information shows, in orange, 2 contacts that are to worry
The max. penetration value helps us define the Pinball Radius, for the contact to work without interference; this is why we used 0.05 mm, bigger than the max. penetration 241
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For an easier view on the piston, select any face of the block, right click, Hide Body
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For Mobile, Scope, select the 4 outer faces of the corresponding piston (green here), Apply
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Right click any where, Show All Bodies; for verification, this is how the Translational joint looks like, when it's finished
Solution, Stress, Equivalent (von-Mises)
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Select all the pistons, Apply
Select the crankshaft, Apply
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Solution, Probe, Force Reaction
Location Method, Contact Region, select the last contact from the drop down list
Duplicate the Force Reaction
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Change the Contact Region, as seen here
Solution, Tools, Contact Tool
Uncheck the last 4 contacts, to have only the first ones active, as seen here
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Right click Status, Duplicate
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Selecting Solution, Information, this is the log of the solver, called Solver Output
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Change Solver Output to Force Convergence to obtain a graphical representation of the Choosingsolver's Force Convergence activity; we instead of Solver that Output will observe theyou analysis obtain such a plot that shows a converges nicely nice convergence trend
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After ~1 hour of solving time, this is the Total Deformation plot
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This is the Directional Deformation plot in pistons
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Finite Element Analysis Hints and Ansys Workbench Tutorial
STATIC STRUCTURAL DETAILED FEA OF VERIFICATION OF M10 SCREWS USING BOLT PRETENSION
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CONTENT:
1. Introduction.................................................................... page 3 2. Advice and good practices for a future FEA engineer...... page 4 3. What we learn in this tutorial........................................... page 16 4. Static Structural detailed FEA of verification of M10 screws using Bolt Pretension................................................................... page 17 5. The end........................................................................... page 54
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3. What we learn in this tutorial
- to properly set-up the Contacts , Named Selections, Object Generator - to investigate the validity of the results with Structural Error tool - to optimize the geometry and the mesh where needed - to define proper output for stress, strain, tools etc. - to re-run the FEA with non-linear materials
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4. Static Structural FEA of verification of M10 screws using Bolt Pretension
Firstly, make sure that you have a proper geometry, like the one we provide, shown here
Double click Static Structural from Toolbox. Right click Geometry, Import Geometry, Browse... " 2013_12_20_flanges_bolts1.x_t"
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For last 4 features, let us change the measurement unit to MPa, as seen here
For the very common bolt steel with 8.8 grade, insert these values 257
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Refresh Project, Return to Project
Right click Model, Edit...
Right click Component2, Rename to: "nut M10"; right click Component1, Rename to: "bolt M10"
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To set the mesh size for the rest of the parts, right click on Body Sizing, Duplicate
Click Geometry, 8 Bodies, zoom with middle mouse to properly select the flanges and the spacer between them, Apply, Element Size = 4 mm
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Make sure you have checked Named Selections toolbar from View menu
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With selection filter on Face, select with Ctrl pressed the 4 cylinders of the bolts (green here), than press Create Named Selection button
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Uncheck the contact from the ring and the bonded ones, as seen here
Right click Status, Duplicate
Change Type of Status 2 to Pressure
Right click Pressure, Duplicate
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Change Type of Pressure to Penetration
Right click Solution Information, Solve
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This is how Solver Output shows the activity of the solver
Change Solver Output to Force Convergence for a graphical representation of the solver's activity
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This is the force Convergence plot where we will see when the solver converges
After the successful finish of the solving, make sure that the results scale is 1 and check the axial Directional Deformation
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This is the stress only in the bolts; click on the upper Probe button than on different points to find out the stress where needed; compared to the Yield Stress of 640 MPa, we are exactly fine
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After we have adjusted the legend to visible, this is the Safety Factor plot in the M10 screws, related to Yield Stress
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To illustrate the Contact Tool, use 4 viewports pressing the respective button in the upper toolbar
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Finite Element Analysis Hints and Ansys Workbench Tutorial
STATIC STRUCTURAL FEA OF A PIN LARGELY DEFORMING A RUBBER SEALING 269
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CONTENT:
1. Introduction.................................................................... page 3 2. Advice and good practices for a future FEA engineer...... page 4 3. What we learn in this tutorial........................................... page 16 4. Static structural FEA of a pin largely deforming a rubber sealing................................................................... page 17 5. The end........................................................................... page 35
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3. What we learn in this tutorial
- to assign hyperelastic and plastic materials - to set-up a proper mesh with dropped midside nodes - to correctly assign contacts between distinct parts and between features of the same part - to set-up a multi-step Static Structural FEA - to define proper output for stress, strain, tools etc.
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4. Static structural FEA of a pin largely deforming a rubber sealing
Firstly, make sure that you have a proper geometry, like the one we provide, shown here
Drag Static Structural from Toolbox to Project Schematic. Right click Geometry, Import Geometry, Browse... " 2014_01_29_sealing_1lip4.x_t " 272
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On the Environment toolbar, choose Supports, Displacement
Select the outer face of the pin, Apply. X and Z Component = 0 mm and for Y Component choose Tabular Data.
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Insert these values in Y column.
On the Environment toolbar, choose Supports, Fixed Support.
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Click the green face, than propagate the selection with Extend to Limits, Apply.
On the Solution toolbar, choose Deformation, Total.
Solution toolbar, Deformation, Directional.
Orientation = Y Axis
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Solution, Stress, Equivalent (von-Mises). Solution, Strain, Equivalent (von-Mises).
Select the sealing, Apply.
Solution, Tools, Contact Tool.
We are not interested of what happens between the polyethylene reinforcement and the surrounding rubber, so uncheck the Bonded contact, as seen here
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Right click Contact Tool, Insert, Pressure
Solution, Probe, Force Reaction.
Location Method = Contact Region. Contact Region = Frictionless - pin To sealing.
Right click Solution (A6), Solve.
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During solving, if you select Solution Information = Force Convergence, you will get a similar plot, very helpful on judging the tendency of the solution computation.
Scope only for the reinforcement, Apply.
Right click Equivalent Stress, Evaluate All Results.
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This is the Stress plot only in the reinforcement.
This is the Status of the Contact Tool.
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Finite Element Analysis Hints and Ansys Workbench Tutorial
TRANSIENT STRUCTURAL FEA OF A SMALL SKID STEER LOADER
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CONTENT:
1. Introduction.................................................................... page 3 2. Advice and good practices for a future FEA engineer...... page 4 3. What we learn in this tutorial........................................... page 16 4. Transient structural FEA of a small skid steer loader....... page 17 5. The end........................................................................... page 49
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3. What we learn in this tutorial
- to work with both rigid and flexible bodies - to correctly assign many different joints (23) - to set-up a multi-step Transient Structural FEA - to define proper output for stress, deformation, velocity, probes etc.
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4. Transient structural FEA of a small skid steer loader
Firstly, make sure that you have a proper geometry, like the one we provide, shown here.
Drag Transient Structural from Toolbox to Project Schematic. Right click Geometry, Import Geometry, Browse... " 2013_10_18_loader_asm.x_t ". 283 © expertfea.com expertfea.com
Right click Model, Edit...
Select first 9 components (green here), with Shift pressed and make Stiffness Behavior, Rigid.
Right click Contacts, Delete. 284
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From the upper Connections toolbar, choose Body-Ground, Fixed.
Let us fix the loader body: select the underside, green here, Apply.
From the Connections toolbar, choose Body-Ground, Revolute.
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Select the green surface from Component10, Apply. Repeat the Revolute Joint for the Component15 on the other side.
Selecting with Shift pressed all 23 joints, they should look like here. 11 pairs of mirrored joints and 1 joint fixes the excavator body. 286
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Click Analysis Settings and make Number of Steps = 10. Select with Shift pressed all 10 steps from the lower right Graph tab and insert these values for Initial, Minimum and Maximum Time Step
To simulate a load in the hoe, right click Transient (A5), Insert, Pressure
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Click inside of the hoe, Apply. Magnitude = 0.07 MPa
Choose from Solution toolbar, Stress, Equivalent (von-Mises)
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With selection filter on Body, click the 5 parts, green here, Apply Choose from Solution toolbar, Deformation, Directional
Select only the hoe, Apply. Orientation, Y Axis. 289
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To see how the FEA evolves, make Solution Output, Force Convergence. Display Points, 35
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This is the Stress in pistons.
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