WS15c-1 WORKSHOP 15C MODAL ANALYSIS OF TUNING FORK USING FINE MESH WITH TET4 ELEMENTS NAS122, Workshop 15c, August 2005 Copyright 2005 MSC.Software Corporation

WS15c-2 NAS122, Workshop 15c, August 2005 Copyright 2005 MSC.Software Corporation

WS15c-3 NAS122, Workshop 15c, August 2005 Copyright 2005 MSC.Software Corporation MODAL ANALYSIS OF A TUNING FORK n Problem Description u In this workshop, the user will compare the results based on different type of Tet mesh. The user will continue using the database from Workshop 15a, and mesh the tuning fork model using Tet4 elements. The purpose is to see if the Eigenvalue and the Mode shapes changed due to the different type of Tet elements used.

WS15c-4 NAS122, Workshop 15c, August 2005 Copyright 2005 MSC.Software Corporation MODAL ANALYSIS OF A TUNING FORK n Suggested Exercise Steps 1. Open the database created in Workshop 15a. 2. Delete the finite elements that are on the model. 3. Mesh the model with TET4 elements and allow Patran to automatically calculate the Global Edge Length. 4. Submit the model to Nastran for a Normal Modes analysis. 5. Attach the XDB result file after the analysis is completed. 6. Use the Deformation feature in the Result Menu to visualize the Eigenvector of the model.

WS15c-5 NAS122, Workshop 15c, August 2005 Copyright 2005 MSC.Software Corporation Step 1. File / Open Open the database created in Workshop 15a. a.File / Open. b.Select tuning fork.db as the file name. c.Click OK. a b c

WS15c-6 NAS122, Workshop 15c, August 2005 Copyright 2005 MSC.Software Corporation Step 2. Elements: Delete / Any Delete the finite elements generated before. a.Elements: Delete / Any. b.Use the rectangular picking option to pick all the elements. c.Click Apply. a b c

WS15c-7 NAS122, Workshop 15c, August 2005 Copyright 2005 MSC.Software Corporation Step 3. Elements: Create / Mesh / Solid Create the finite element mesh for the model. a.Elements: Create / Mesh / Solid. b.Use Tet for Elem Shape. c.Select Tet4 for the Topology. d.Pick the solid model from the screen for the Input List. e.Check the Automatic Calculation box. f.Click Apply. a b c d e f

WS15c-8 NAS122, Workshop 15c, August 2005 Copyright 2005 MSC.Software Corporation Step 4. Analysis: Analyze / Entire Model / Full Run Submit the tuning fork for normal modes analysis. a.Analysis: Analyze / Entire Model / Full Run. b.Enter tuning_fork_tet4 for the Job Name. c.Click on Solution Type. d.Select NORMAL MODES. e.Click on Solution Parameters. f.Change the Wt-Mass Conversion to g.Click OK on both sub-forms. h.Click Apply to submit the model for analysis. a b d e f g g h c

WS15c-9 NAS122, Workshop 15c, August 2005 Copyright 2005 MSC.Software Corporation Step 5. Analysis: Access Results / Attach XDB / Result Entities Attach the XDB result file. a.Analysis: Access Results / Attach XDB / Result Entities. b.Click on Select Results File… c.Select tuning_fork_tet4.xdb. d.Click OK. e.Click Apply. a b c d e

WS15c-10 NAS122, Workshop 15c, August 2005 Copyright 2005 MSC.Software Corporation Step 6. Results: Create / Deformation Create a Deformation Plot of the models Mode Shape. a.Results: Create / Deformation b.Select the A3: Mode 7. c.Select Eigenvector, Translational for the Deformation Result. d.Click Apply. b a c d

WS15c-11 NAS122, Workshop 15c, August 2005 Copyright 2005 MSC.Software Corporation Summary Summary of Frequencies and Modes for project _______________ ModeFreq (Hz) Description

WS15c-12 NAS122, Workshop 15c, August 2005 Copyright 2005 MSC.Software Corporation