PAT301, Workshop 15, October 2003 WS15-1 WORKSHOP 15 USING LISTS AND GROUPS
WS15-2 PAT301, Workshop 15, October 2003
WS15-3 PAT301, Workshop 15, October 2003 n Problem Description u In this exercise, a portion of a fairing will be constructed. Curves and surfaces will be used to define the fairing geometry. The finite element model will consist of 2-dimensional elements with 1- dimensional elements applied at various edges of the geometry. The 1-dimensional elements will represent stiffeners for the structure.
WS15-4 PAT301, Workshop 15, October 2003 n Suggested Exercise Steps 1. Create a new database called fairing.db and set the model preferences. 2. Create the model geometry. 3. Create the mesh seeds for the model. 4. IsoMesh the model using Quad4 topology. 5. Check the free edges, equivalence the model, and then check the free edges again. 6. Create a new group called FEM that contains only the finite elemental model. Then post only the FEM group. 7. Create two material properties, alum_1 and alum_2. 8. Create two fields, one for temperature and the other for thickness. 9. Create element properties. 10. Create a temperature boundary condition. 11. Create a series of lists containing elements that satisfy these following requirements: 1) the elements are made up of the alum_1 material, 2) the elements are greater than 0.98 in thickness, and 3) the elements have a temperature greater than degrees. 12. Intersect lists a and b to produce a list of elements that satisfy the first two conditions.
WS15-5 PAT301, Workshop 15, October 2003 n Suggested Exercise Steps (Cont.) 13. Create another list that satisfies the third condition. 14. Intersect the new list with the other list to produce a group of elements that satisfy all three conditions. Then, place these elements in a separate group. 15. Post the group containing the elements produced in step Create 2 new groups, each containing elements with different property sets. 17. Change the display attributes for each group. 18. Post each group separately, then post both groups together.
WS15-6 PAT301, Workshop 15, October 2003 Step 1. Create New Database Create a new database and set the model preferences. a. File : New. b. Enter fairing for the File Name. c. Click OK. d. Set the Tolerance to Default. e. Make sure that the Analysis Code and Analysis Type are set to MSC.Nastran and Structural, respectively. f. Click OK. a b c d e f
WS15-7 PAT301, Workshop 15, October 2003 Step 2. Create Model Geometry Create the points and curves that represent the outline of the fairing. a. Geometry : Create / Point / XYZ. b. Turn Auto Execute off. c. Enter [30 0 0] under Points Coordinates List and click Apply. d. Geometry : Create / Curve / XYZ. e. Turn Auto Execute off and enter and [ ] under Vector Coordinates List and Origin Coordinates List, respectively. f. Click Apply. g. Click on Show Labels icon. h. Click on Point Size icon to increase the point size. i. Geometry : Create / Curve / Point. j. Turn Auto Execute off. k. Click on Point 1 under Starting Point List and click on Point 2 for Ending Point List. l. Click Apply. a d ce f i k l gh b j
WS15-8 PAT301, Workshop 15, October 2003 Step 2. Create Model Geometry (Cont.) Illustrated here are curves that represent the basic geometry for the fairing. These curves will be revolved 360º to get the final model.
WS15-9 PAT301, Workshop 15, October 2003 Step 2. Create Model Geometry (Cont.) Create the fairing by revolving curves 1 and 2 about the fairings vertical center line. a. Geometry : Create / Surface / Revolve. b. Enter Coord 0.2 for Axis c. Enter 360 for the Total Angle. d. Turn Auto Execute off. e. Shift-select curves 1 and 2. f. Click Apply. g. Viewing : Angles… h. Enter under Angle. i. Click Apply. a b c e f g h i d
WS15-10 PAT301, Workshop 15, October 2003 Step 2. Create Model Geometry (Cont.) Change the display preferences in order to get a clearer visual of the model. a. Display : Geometry… b. Enter 3 for Number of Display Lines c. Click Apply, then Cancel. a b c
WS15-11 PAT301, Workshop 15, October 2003 Step 3. Create Mesh Seeds Create a finite elemental mesh so that 4 node Quad elements are created every 10° along the circumferential edges. a. Elements : Create / Mesh Seed / Uniform. b. Select Number of Elements and enter 36 for the Number. c. Select the top circumferential edge of the fairing(Surface 1.3) and click Apply. a b c
WS15-12 PAT301, Workshop 15, October 2003 Step 3. Create Mesh Seeds (Cont.) In the vertical direction(y-direction), define a smoothly transitioning mesh density. The elements along the top of the cylinder are 2.5 times as large as those along the bottom edge (tapered end) of the fairing. a. Elements : Create / Mesh Seed / One Way Bias. b. Select L1 and L2 and enter 7 and 10 for L1 and L2, respectively. c. Turn Auto Execute off. d. Under Curve List, Select Curve 1 and click Apply. e. Elements : Create / Mesh Seed / One Way Bias. f. Select L1 and L2 and enter 4 and 7 for L1 and L2, respectively. g. Under Curve List, Select Curve 2 and click Apply. a d b e f g c
WS15-13 PAT301, Workshop 15, October 2003 Step 4. Create Model Meshes Now that the mesh seeds have been created, mesh the model using Quad4 topology. a. Elements : Create / Mesh / Surface. b. Select Quad, IsoMesh, and Quad4. c. Select the entire model by dragging a box around it. And click Apply. d. Remove the display lines by clicking the on the Display lines icon. e. Remove the labels by clicking the Hide labels icon. f. Decrease the point-size clicking on the Point Size icon. a b c edf
WS15-14 PAT301, Workshop 15, October 2003 Step 4. Create Model Meshes(Cont.) Mesh the horizontal (circumferential) edges of each surface with two- noded bar elements. a. Click on Plot/Erase icon and click on Erase under FEM. b. Click OK. c. Elements : Create / Mesh / Curve. d. Set Topology to Bar2 e. Shift select the 3 surface edges (as indicated). f. Click Apply. b c d e f a e
WS15-15 PAT301, Workshop 15, October 2003 Step 5. Observe the Free Edges Check the free edges of the model, equivalence, and then check the free edges again. a. Elements : Verify / Element / Boundaries. b. Select Free Edges under Display Type. c. Click Apply. d. Elements : Equivalence / All / Tolerance Cube. e. Click Apply. f. Repeat steps a through c. a b c d e The middle yellow line does not indicate Quad 4s with free edges, but the presence of Bar2 elements.
WS15-16 PAT301, Workshop 15, October 2003 Step 6. Create a Group Replot the FEM and create a group called FEM containing only the finite elemental model. Post only this new group to the viewport. a. Click on the Plot/Erase icon. b. Under FEM, click Plot. c. Click OK. d. Group : Create… e. Enter FEM for the New Group Name. f. Select Unpost All Other Groups. g. Change Group Contents to Add All FEM. h. Click Apply. a b c d e f g h
WS15-17 PAT301, Workshop 15, October 2003 Step 7. Create Material Properties Create the first material for the model. Material alum_1 will be applied to the top(cylindrical) portion of the fairing. a. Materials : Create / Isotropic / Manual Input. b. Enter alum_1 for the Material Name. c. Click on Input Properties… d. Select Linear Elastic and enter 1.05E7, 0.33, and 2.6E-4, for Elastic Modulus, Poisson Ratio, and Density, respectively. e. Click OK. f. Click Apply. a b c d e f
WS15-18 PAT301, Workshop 15, October 2003 Step 7. Create Material Properties (Cont.) Create the second material for the model. Material alum_2 will be applied to the bottom(tapered) portion of the fairing. a. Materials : Create / Isotropic / Manual Input. b. Enter alum_2 for the Material Name. c. Click on Input Properties… d. Select Linear Elastic and enter 1.18E7, 0.33, and 2.4E-4, for Elastic Modulus, Poisson Ratio, and Density, respectively. e. Click OK. f. Click Apply. a b c d e f
WS15-19 PAT301, Workshop 15, October 2003 Step 8. Create a Field Define fields that represent the varying thickness and temperature distribution. a. Fields : Create / Spatial / PCL Function. b. Enter thickness for the Field Name. c. Enter 1.5-Y/160 for the Scalar Function and click Apply. d. Fields : Create / Spatial / PCL Function. e. Enter temperature for the Field Name. f. Enter (150.0/160.0)*X for the Scalar Function and click Apply. a b c d e f
WS15-20 PAT301, Workshop 15, October 2003 Step 9. Create Element Properties Create two element properties which include the material definitions and varying thickness. a. Click on the Front view icon. b. Properties : Create / 2D / Shell. c. Enter prop_1 for the Property Set Name. d. Click on Input Properties. e. Click on Material Property Name icon and select alum_1 from Select Existing Material. a b c d e
WS15-21 PAT301, Workshop 15, October 2003 Step 9. Create Element Properties (Cont.) Finish creating the first property set. a. Click on Thickness icon and select thickness under Select Existing Field. b. Click OK. c. Preferences : Picking and set Rectangle/Polygon Picking to Enclose entire entity d. Click on Select Members and click on the Shell element icon. Select the top(cylindrical) portion of the fairing by dragging a box around the desired section(as indicated on next page). e. Click Add, then Apply. a b d e c d
WS15-22 PAT301, Workshop 15, October 2003 Step 9. Create Element Properties (Cont.) Illustrated here is the desired application region for the first property set.
WS15-23 PAT301, Workshop 15, October 2003 Step 9. Create Element Properties (Cont.) Create the second property set. a. Properties : Create / 2D / Shell. b. Enter prop_2 for the Property Set Name. c. Click on Input Properties… d. Click on Material Property Name icon and select alum_2 from Select Existing Material. e. Click on Thickness icon and select thickness from Select Scalar Spatial Field. f. Click OK. g. Click on Select Members and select the bottom(tapered) portion of the fairing by dragging a box around it(as indicated on next page). h. Click Add, then Apply. a b c d e f g h
WS15-24 PAT301, Workshop 15, October 2003 Step 9. Create Element Properties (Cont.) Shown here are the elements for the desired application region of the second property set.
WS15-25 PAT301, Workshop 15, October 2003 Step 10. Create Temperature Boundary Conditions Define the models varying temperature distribution. a. Loads/BCs : Create / Temperature / Nodal. b. Enter temp for the New Set Name. c. Click on Input Data… d. Click on Temperature and select temperature from the Spatial Fields. e. Click OK. f. Click on Select Application Region. g. Under Geometry Filter, select FEM. h. Click on Application Region and select the entire model(All nodes). i. Click Add, then, OK j. Click Apply. a b c d e f g h i j
WS15-26 PAT301, Workshop 15, October 2003 Step 10. Create Temperature Boundary Conditions (Cont.) Turn off the temperature labels in order to get a better visualization of the model. a. Display : Load/BC/Elem. Props… b. Under Loads/BCs remove check for Temperature. c. Click Apply, then Cancel. a b c
WS15-27 PAT301, Workshop 15, October 2003 Step 11. Create Lists Use Lists and groups to filter then group the quad elements that have the following attributes: Material : alum_1 Thickness : > 0.98 Temperature : >230.0 a. Tools : List / Create… b. FEM / Element / Attribute c. Under Attribute select Material. d. Under Existing Materials select alum_1. e. Set the Target List to A and click Apply. a b c d e List A consists of those elements whose properties are specified by alum_1.
WS15-28 PAT301, Workshop 15, October 2003 Step 11. Create Lists (Cont.) Define List B to include only the Quad elements that have a thickness greater than a. Properties : Show. b. Under Existing Properties, select Thickness. c. Set Display Method to Scalar Plot. d. Select Current Viewport, select FEM and click Apply. a b c d Shown above is a fringe plot corresponding to the model thickness. The elements that are thicker than 0.98 will be included in the next list.
WS15-29 PAT301, Workshop 15, October 2003 Step 11. Create Lists (Cont.) After defining the list parameters, add the elements with thickness greater than 0.98, to list B. a. Tools : List / Create… b. FEM / Element / Attribute. c. Under Attribute select Fringe Value. d. Under Fringe Tools select default_Fringe. e. Change F to > and enter f. Select B for the Target List. g. Click on Apply. a b c d e f g The contents of List B include all elements thicker than 0.98.
WS15-30 PAT301, Workshop 15, October 2003 Step 12. Intersect Lists Intersect Lists A and B and replace the contents of List A with the elements found in the intersection. a. Tools : List / Boolean… b. Click on the Intersect icon. c. Click on Replace A. d. Click Cancel. The new List A is composed of elements that satisfy both requirements: they are in set alum_1 and thicker than a b c d
WS15-31 PAT301, Workshop 15, October 2003 Step 13. Create More Lists Perform a final classification of the elements. Isolate those elements that satisfy the third condition of the applied temperature load > a. Loads/BCs : Plot Contours / Temperature. b. Select temp from the Existing Sets. c. Select Temperature under Select Data Variable. d. Select the FEM group and click Apply. Illustrated here is the temperature fringe plot for the model. a b c d
WS15-32 PAT301, Workshop 15, October 2003 Step 13. Create More Lists (Cont.) Clear the contents of List B and add the values obtained from the final classification. a. Tools : List / Create. b. FEM / Element / Attribute. c. Select Fringe Value and default_Fringe for Attribute and Fringe Tools, respectively. d. Change F to > and enter e. Select B for the Target List. f. Click on Clear on the List B form g. Click Apply on the List Create form. a b c d e f g
WS15-33 PAT301, Workshop 15, October 2003 Step 14. Intersect Lists Again Lists A and B will be intersected again to create a List C. This list will contain the elements that satisfy all three conditions. The contents of List C will then be placed into a new group called common_quads. a. Tools : List / Boolean… b. Click Clear. c. Click on the Intersect icon. d. Click on Add To Group… e. Enter common_quads for the Group Name. f. Click Apply, then Cancel. a b c d e f
WS15-34 PAT301, Workshop 15, October 2003 Step 15. Post Group Post the common_quad group. This is the group of elements that satisfy all three of the conditions defined earlier. a. Group : Post… b. Select the common_quads group under Select Groups to Post. c. Click Apply, then Cancel. d. Click on the Iso 1 view icon. a b c d
WS15-35 PAT301, Workshop 15, October 2003 Step 15. Post Group (Cont.) This is the Iso 1 view of the elements in the common_quads group. These are all the elements that satisfied all three conditions.
WS15-36 PAT301, Workshop 15, October 2003 Step 16. Create Two New Groups Create two new groups, prop1_group and prop2_group. Then, change the display attributes for each group. a. Click on the Reset Graphics icon. b. Group : Create… c. Create / Property Set. d. Enter prop1_group for the Group Name. e. Select prop_1 under Property Sets and click Apply. f. Repeat steps b through e entering prop2_group for the Group Name and selecting prop_2 under Property Sets. a b c d e f
WS15-37 PAT301, Workshop 15, October 2003 Step 17. Change the Display Attributes Set the entity coloring and labeling to Group mode and then change the display attributes for each of the two new groups. a. Display : Entity Color / Label / Render… b. Select Group under Entity Coloring and Labeling. c. Select the prop1_group under the Target Group(s). d. Select Wireframe for the Render Style and select yellow for the Shade Color. e. Click Apply. f. Select the prop2_group for the Target Group(s). g. Select Hidden Line for the Render Style and select dark blue for the Shade Color. h. Click Apply, then, Cancel. a b c d e f g h
WS15-38 PAT301, Workshop 15, October 2003 Step 18. Post Groups Change views and post the prop1_group. a. Click on the Iso 3 view icon. b. Group : Post… c. Under Select Groups to Post, select prop1_group. d. Click Apply. a b c d
WS15-39 PAT301, Workshop 15, October 2003 Step 18. Post Groups (Cont.) Post only the prop2_group. a. Group : Post… b. Under Select Groups to Post, select prop2_group. c. Click Apply. a b c
WS15-40 PAT301, Workshop 15, October 2003 Step 18. Post Groups (Cont.) Post both the prop1_group and the prop2_group. a. Group : Post… b. Under Select Groups to Post, select both prop1_group and prop2_group. c. Click Apply. a b c