Ws07_parasolid.ppt

1、WORKSHOP 7PARASOLID SOLID EXAMPLE,PAT301, Workshop 7, May 2002,WS7-1,Problem Description Create a parasolid solid model of a tension fitting. This is done using some of the parasolid tools in MSC.Patran, e.g. boolean. Create a tet10 solid element mesh model, including the needed load and constraint,

2、 material and element properties, and analysis input. Run the finite element analysis using MSC.Nastran. Then, display the deformation and stress results in Patran.,Suggested Exercise Steps Create a new database for the tension fitting model. Create all the necessary 2D Geometry. Extrude the surface

3、 to begin creating the solid model. Create a solid shell by removing part of the solid. Create fillets for all inside edges of the solid. Create holes for the model by creating solid cylinders that pass through it, and then use boolean to subtract the cylinders. Create cylinders to imprint the model

4、. Imprint the solid using the cylinders. Delete the cylinders used for imprinting. TetMesh the completed solid Create loads and constraints on the model that will be used in the analysis. Create material properties for the model. Create the 3D element properties. Check to see that the load case Defa

5、ult has the load and constraint. Run the analysis by sending the model to MSC.Nastran. Access the results by attaching the XDB file. Post-process the results from MSC Nastran.,Step 1. Create New Database for Tension Fitting,Create a new database called tension_fitting.db. a. File / New. b. Enter ten

6、sion_fitting as the file name. c. Click OK.,Step 2. Create Surface,Create the Geometry for the tension fitting. a. Geometry : Create / Surface / XYZ. b. Enter for Vector Coordinates List. c. Enter 0 0 0 for Origin Coordinates List. d. Click Apply.,Step 2. Create Surface (Cont.),Copy points at opposi

7、te corners. a. Click increase Point Size icon to show all points enlarged. b. Geometry : Transform / Point / Translate. c. Enter for Translation Vector. d. Select top-left corner and click Apply. e. Enter for Translation Vector. f. Select bottom-right corner and click Apply.,Step 2. Create Surface (

8、Cont.),Create a curve by connecting the two translated points and break the surface with the curve. a. Geometry : Create / Curve / Point. b. Click on one of the two points from translation as the starting point and the other as the ending point. c. Click Apply.,Step 2. Create Surface (Cont.),Break t

9、he surface and delete the upper portion of the original surface. a. Geometry : Edit / Surface / Break. b. Select the rectangular surface for the Surface List and the sloped curve for the Break Curve List. c. Click Apply and Yes when message box appears. d. Click the Refresh Graphics icon.,Step 2. Cr

10、eate Surface (Cont.),Delete the upper surface (above the break curve). a. Geometry : Delete / Surface. b. Click on the triangular surface for the Surface List. c. Click Apply.,Create a parasolid solid by extruding the surface in the z-direction. a. Geometry : Create / Solid / Extrude. b. Make sure T

11、etMeshable solid icon is selected. c. Enter for the Translation Vector. d. Click Apply. e. Click Iso1 view. f. Click the Smooth- shaded icon.,Step 3. Extrude the Surface to Create Solid,Step 4. Create a solid shell,Edit the solid using the shell method to create a shelled solid. a. Geometry : Edit /

12、 Solid / Shell b. Enter 0.25 for Thickness. Turn off Auto Execute. c. Click on Solid Face List and hold down the shift button and select the top, sloped, and front faces of the solid. d. Click Apply.,Step 5. Create Fillets,Create the fillets on the inner edges of the solid. a. Geometry : Edit / Soli

13、d / Edge Blend. b. Make sure that the constant radius icon is selected. c. Enter 0.25 for Constant Radius. d. Make sure Edges of Solid icon is selected. e. Click on Solid Edge List and use the shift-click technique and select the 3 edges on the inside of the solid. f. Click Apply.,It may be necessar

14、y to rotate the object in order to see then inner edges more easily. This can be done by holding the middle mouse button and moving the mouse.,Step 6. Create Holes for the Tension Fitting,Create the holes for the tension fitting by creating primitive solids that pass through the solid, then subtract

15、ing them. a. Geometry : Create / Solid / Primitive. b. Select the cylinder icon c. Enter 2.0 for the Height and 0.25 for the radius. d. Enter -1 1.25 1 for the Base Center Point List and Coord 0.1 for the Axis List. e. Click Apply. f. Geometry : Edit / Solid / Boolean. g. Select Subtract icon. h. Se

16、lect the tension fitting for the Target Solid. i. Select the cylinder for the Subtracting Solid List. j. Click Apply.,Step 6. Create Holes for the Tension Fitting (Cont.),Create the points where the three bottom holes will be placed by translating an existing point and, then translating again. a. Cl

17、ick wireframe icon. b. Geometry : Transform / Point / Translate. c. Enter for Translation Vector. d. Select point at base edge of fillet and click Apply. e. Enter for Translation Vector. f. Select translated point and click Apply. g. Enter for Translation Vector. h. Enter 2 for repeat count. i. Sele

18、ct translated point and click Apply.,Step 6. Create Holes for the Tension Fitting (Cont.),Create cylinders using points as base centers and then create holes by subtracting them from the solid. a. Click Smooth shaded icon. b. Geometry : Create / Solid / Primitive. c. Select cylinder icon. d. Enter -

19、1.0 for Height List and 0.125 for Radius List. e. Use the shift-click technique to select the three translated points for Base Center Point List. f. Enter Coord 0.2 for axis list and click Apply. g. Geometry : Edit / Solid / Boolean. h. Select subtract icon i. Select tension fitting as Target Solid.

20、 j. Shift-click all three cylinders for Subtracting Solid List. k. Click Apply.,It may be necessary to rotate the object several times in order to select the cylinders with ease,Step 7. Create Cylinders to Imprint Tension Fitting,Create a point in the center of the big hole in order to create the cy

21、linder to imprint onto the solid. Then create all four cylinders that will be used for Imprinting. a. Click wireframe icon. b. Geometry : Create / Point / ArcCenter. c. Select the larger hole edge. d. Geometry : Create / Solid / Primitive. e. Select cylinder icon f. Enter 1.0 for Height and 0.371 fo

22、r Radius. g. Click on point in the center of the big hole. h. Enter Coord 0.1 for Axis List. i. Click Apply. j. Select Smooth Shaded icon.,Step 7. Create Cylinders to Imprint Tension Fitting (Cont.),Now, create the three cylinders that will be used to imprint the base of the tension fitting. a. Clic

23、k wireframe icon. b. Geometry : Create / Solid / Primitive. c. Select cylinder icon d. Enter 0.5 for Height and 0.298 for Radius. e. Shift-click on point in the center of each of the base holes. f. Enter Coord 0.2 for Axis List. g. Click Apply. h. Select Smooth Shaded icon.,Step 8. Imprint the Solid

24、,Use the cylinders to imprint the solid and then delete the cylinders, resulting in the finished solid. a. Geometry : Edit / Solid / Imprint. b. Shift-click all four cylinders under Imprinting Solid List. c. Select the tension fitting for the Imprinted Solid List. d. Click Apply.,The solid may seem

25、unchanged, but the imprints on the solid will not be visible until the all the cylinders have been deleted.,Step 9. Delete the Cylinders,Delete the cylinders and make sure imprint method was completed. a. Geometry : Delete / Solid b. Shift-click all four cylinders for Solid List. c. Click Apply.,The

26、 imprints created from the previous step are now visible. Imprinting is used to show where washers on an object will be placed. It allows for application of a total load over the imprinted area, which will be performed later,Step 10. TetMesh the Completed Solid,Create the TetMesh for the tension fit

27、ting. a. Elements : Create / Mesh / Solid. b. Make sure Tet, TetMesh, and Tet10 are all selected. c. Click on Input List and select all solid. d. Remove check for Automatic Calculation and enter 0.25 for Global Edge Length. e. Click Apply.,Step 11. Create Loads and Constraints,Create the loads and c

28、onstraints for the model. Click Smooth Shaded icon Loads/BCs : Create / Total Load / Element Uniform. Enter Force as the New Set Name. Click Input Data Enter for the Load and click OK. Click Select Application Region Select the vertical solid face created by imprinting at the larger hole, then click

29、 Add. Click OK Click Apply.,Illustrated here is the desired application region.,Step 11. Create Loads and Constraints (Cont.),Step 11. Create Loads and Constraints (Cont.),Create the constraints on the base holes. a. Loads/BCs : Create / Displacement / Nodal. b. Enter Fixed as New Set Name. c. Click

30、 Input Data d. Enter for Translation only, and click OK. e. Click Select Application Region. f. Click on Select Geometry Entities. g. Select Surface or Face icon h. Shift-click the surface(inside) of the three holes on the base, and Click Add. i. Click OK. j. Click Apply.,Illustrated here is the des

31、ired application region for one of the three holes.,Step 11. Create Loads and Constraints (Cont.),Step 12. Create Material Properties,Create the material properties for the model. a. Materials : Create / Isotropic / Manual Input b. Enter Aluminum for Material Name. c. Click Input Properties d. Enter

32、 10E6 for Elastic Modulus and 0.3 for the Poisson Ratio. e. Click OK f. Click Apply.,Step 13. Create 3D Element Properties,Create the 3D element properties for the tension fitting. a. Properties : Create / 3D / Solid. b. Enter 3D_tets for Property Set Name. c. Click Input Properties d. Select Alumin

33、um from Material Property Sets for Material Name. e. Click OK f. For Application Region, select entire solid by dragging a box around it and click Add. g. Click Apply.,Step 14. Check the Load Case,Check the load case Default to make sure that the load and constraint are selected. a. Load Cases : Mod

34、ify b. Click on the load case name Default. c. Check to see that both the load and constraints are assigned. d. Click Cancel.,Step 15. Run the Analysis,Run the Analysis with MSC.Nastran. a. Analysis : Analyze / Entire Model / Full Run. b. Click Translation Parameters. c. Make sure XDB and Print is s

35、elected. d. Click OK. e. Click Solution Type f. Make sure LINEAR STATIC is selected. g. Click OK. h. Click Apply.,Step 16. Access the Results,Attach the XDB file and access the results. a. Analysis : Attach XDB / Result Entities / Local. b. Click Select Results File c. Select tension_fitting.xdb and click OK. d. Click Apply.,S