WS15a-1 WORKSHOP 15A MODAL ANALYSIS OF A TUNING FORK USING FINE MESH WITH TET10 ELEMENTS NAS122, Workshop 15a, August 2005 Copyright 2005 MSC.Software Corporation

WS15a-2 NAS122, Workshop 15a, August 2005 Copyright 2005 MSC.Software Corporation

WS15a-3 NAS122, Workshop 15a, August 2005 Copyright 2005 MSC.Software Corporation MODAL ANALYSIS OF A TUNING FORK n Problem Description u The user will import a tuning fork model and mesh it with Tet10 elements to create a finite element model. The model will be submit the MSC.Nastran for a normal modes analysis and the user will use MSC.Patran to observe the resulting eigenvalues and modes shapes.

WS15a-4 NAS122, Workshop 15a, August 2005 Copyright 2005 MSC.Software Corporation MODAL ANALYSIS OF A TUNING FORK n Suggested Exercise Steps 1. Import the geometry representation of the tuning fork using the tuning fork.xmt_txt file. 2. Mesh the model with TET10 elements and allow Patran to automatically calculate the Global Edge Length. 3. Create a material set to represent the properties of steel. 4. Assign the material properties to the tuning fork model. 5. Submit the model to Nastran for a Normal Modes analysis. 6. Attach the XDB result file after the analysis is completed. 7. Use the Quick Plot feature in the Result Menu to visualize the Eigenvector of the model.

WS15a-5 NAS122, Workshop 15a, August 2005 Copyright 2005 MSC.Software Corporation CREATE NEW DATABASE Create a new database called tuning fork.db. a.File / New. b.Enter tuning fork as the file name. c.Click OK. d.Choose Default Tolerance. e.Select MSC.Nastran as the Analysis Code. f.Select Structural as the Analysis Type. g.Click OK. a b c d e f g

WS15a-6 NAS122, Workshop 15a, August 2005 Copyright 2005 MSC.Software Corporation Step 1. File / Import Import the geometry model of the tuning fork. a.File / Import. b.Select Parasolid xmt as the Source. c.Select tuning fork.xmt_txt. d.Click Apply. e.Click OK when the Parasolid Transmit File Import Summary appears. a b c d e e

WS15a-7 NAS122, Workshop 15a, August 2005 Copyright 2005 MSC.Software Corporation Step 2. Elements: Create / Mesh / Solid Create the finite element mesh for the model. a.Switch to the Iso 3 View. b.Elements: Create / Mesh / Solid. c.Use Tet for Elem Shape. d.Select Tet10 for the Topology. e.Pick the solid model from the screen for the Input List. f.Make sure the Automatic Calculation is checked. g.Click Apply. a b c d e f g

WS15a-8 NAS122, Workshop 15a, August 2005 Copyright 2005 MSC.Software Corporation Step 3. Material: Create / Isotropic / Manual Input Create the material properties. a.Materials: Create / Isotropic / Manual Input. b.Enter steel for the Material Name. c.Click on Input Properties. d.Enter 26.77E6 for Elastic Modulus and 0.3 for Poisson Ratio. e.Enter for the Density. f.Click OK. g.Click Apply. a b c d e f g

WS15a-9 NAS122, Workshop 15a, August 2005 Copyright 2005 MSC.Software Corporation Step 4. Properties: Create / 3D / Solid Assign the Element Properties to the tuning fork model. a.Properties: Create / 3D / Solid. b.Enter tuning_fork for the Property Set Name. c.Click on Input Properties button. d.Click in the Material Prop Name icon, and select steel from the Material Property Sets. e.Click OK. f.Select the solid model from the screen for the Application Region. g.Click Add. h.Click Apply. a b c d e f g h d

WS15a-10 NAS122, Workshop 15a, August 2005 Copyright 2005 MSC.Software Corporation Step 5. Analysis: Analyze / Entire Model / Full Run Submit the tuning fork for normal modes analysis. a.Analysis: Analyze / Entire Model / Full Run. b.Click on Solution Type. c.Select NORMAL MODES. d.Click on Solution Parameters. e.Change the Wt-Mass Conversion to f.Click OK on both sub-forms. g.Click Apply to submit the model for analysis. a b c d e f f g

WS15a-11 NAS122, Workshop 15a, August 2005 Copyright 2005 MSC.Software Corporation Step 6. 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.xdb. d.Click OK. e.Click Apply. a b c d e

WS15a-12 NAS122, Workshop 15a, August 2005 Copyright 2005 MSC.Software Corporation Step 7. Results: Create / Quick Plot Create a Quick Plot of the models Mode Shape. a.Results: Create / Quick Plot b.Select the A1: Mode 7. c.Select Eigenvector, Translational in both Result boxes. d.Click Apply. b c a c d

WS15a-13 NAS122, Workshop 15a, August 2005 Copyright 2005 MSC.Software Corporation Summary Summary of Frequencies and Modes for project _______________ ModeFreq (Hz) Description

WS15a-14 NAS122, Workshop 15a, August 2005 Copyright 2005 MSC.Software Corporation