Engine Gasket Model Instructions

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1 SOL 600 Engine Gasket Model Instructions Demonstrated:! Set up the Model Database! 3D Model Import from a MSC.Nastran BDF! Creation of Groups from Element Properties! Complete the Material Models! Import of Loading and Unloading Curves Using Fields! Complete the Gasket Element Properties! Define the Loads and Boundary Conditions! Define the Analysis Parameters and Output Requests! Run the Analysis! Access and Process the Results

2 2 SOL 600 Set up the Model Database Before importing the block/gasket/cylinder head model, you first need to create a new MSC.Patran database and define the type of model/analysis you intend to generate. The database contains all of the modeling and analysis information for your model. Setting the new model preferences readies the database and provides you with forms tailored for a SOL 600 analysis. Defining picking preferences up front assigns the manner in which you select objects directly from the graphical viewport. To create a new MSC.Patran database: Step 1: On the File menu, click New. Step 2: In the File Name box, type gasket.db and then click OK.

3 CHAPTER Engine Gasket Model Instructions 3 Step 3: In the Analysis Code list, click MSC.Nastran. Step 4: In the Analysis Type list, click Structural, and then click OK. You now have a new database open with the analysis preferences set for a MSC.Nastran structural analysis.

4 SOL 600 To set the picking preferences: Picking preferences define how you select entities in your model directly from the graphical viewport.

4 4 SOL 600 To set the picking preferences: Picking preferences define how you select entities in your model directly from the graphical viewport. For this example, set the picking preferences so that, to select an object the entire object must be enclosed within a drawn boundary. Step 1: On the MSC.Patran Main toolbar, click Preferences and then click Picking. Step 2: From the Picking menu, select the following options: Single Picking: Select Entity. Rectangle/Polygon Picking: Select Enclose entire entity. Click Close.

CHAPTER Engine Gasket Model Instructions 5 3D Model Import from a MSC.Nastran BDF Rather than create the model geometry from scratch and mesh the geometry to define the finite element model, a MSC.

This enables you to focus on the setting up the gasket properties and contact features specifically needed for this example. To import the model nodes, elements, and properties: Step 1: On the MSC.

5 CHAPTER Engine Gasket Model Instructions 5 3D Model Import from a MSC.Nastran BDF Rather than create the model geometry from scratch and mesh the geometry to define the finite element model, a MSC.Nastran Bulk Data file (bdf) is available for this problem. To expedite the example, you will import the finite element model from the bdf along with some material and element properties. This enables you to focus on the setting up the gasket properties and contact features specifically needed for this example. To import the model nodes, elements, and properties: Step 1: On the MSC.Patran Main toolbar, click the Analysis button. Step 2: From the Action list, click Read Input File. Model Data is automatically selected in the Object list. Step 3: Click Select Input File. Step 4: Navigate to the directory containing the bolt_n_gasket.bdf file. Step 5: Click once on bolt_n_gaske.bdf and click OK. Step 6: On the Analysis form, click Apply. The model appears in your viewport.

6 6 SOL 600 Step 7: Review the Nastran Input File Import Summary, then click OK. Step 8: On the MSC.Patran toolbar, click the Fit View button, Smooth shaded button, and the Iso 3 View button. Fit View Smooth shaded Iso 3 View Step 9: Click the Analysis button again to close the Analysis form.

CHAPTER Engine Gasket Model Instructions 7 Creation of Groups from Element Properties By grouping together the elements that comprise each component in the model and defining a name for each group,

7 CHAPTER Engine Gasket Model Instructions 7 Creation of Groups from Element Properties By grouping together the elements that comprise each component in the model and defining a name for each group, you can make assignments and perform tasks on a collective group rather than have to specify individual elements. Because the element properties for each component in the model have already been defined and imported from the bdf, you can form the groups based on elements that share the same element properties. To create groups according to element properties: Step 1: On the MSC.Patran Main toolbar, click Utilities. Step 2: On the Utilities menu, point to Group, and then click Group From Properties. Note: If you receive a Disclaimer message regarding the use of this tool, review the caution notice and click OK.. Step 3: Click Apply, then click Cancel. All group names begin with the prefix prop. Step 4: On the Group menu, click Post.

8 8 SOL 600 Step 5: Highlight the groups shown in the figure below: Step 6: Click Apply. A caution appears alerting you that prop_cylinder_head will be the new current group. Step 7: Click OK.

9 CHAPTER Engine Gasket Model Instructions 9 To display the model using group colors: Step 1: On the Display menu, click Entity Color/Label/Render. Step 2: From the Entity Color/Label/Render menu, select the following options: Entity Coloring and Labeling: Click Group. Target Group(s): Highlight the six group names that begin with prop. Render Style: Select Shaded/Smooth. Click Apply All. Click Cancel. Step 3: On the Utilities menu, point to Group, and then click Group Color.

Click Apply and then click Cancel. On the Display menu, click Light Sources.

10 10 SOL 600 Step 4: From the Group Color menu, select the following options: Assign Colors: Click Automatic. Group Selection: Click Select. Groups to Process: list select the six groups that begin with prop. Click Apply and then click Cancel. On the Display menu, click Light Sources. This will bring up the Light Sources menu. Step 5: Post/Unpost Light Sources: Highlight directional_1, directional_2, and directional_3 as shown below:

11 CHAPTER Engine Gasket Model Instructions 11 Step 6: Click Apply and then click Cancel.

12 SOL 600 Complete the Material Models Basic material property definitions for all the components in the model have already been imported into the database from the MSC.Nastran bdf.

For the gasket, the loading/unloading curves that relate pressure and gap closure will be read into the database using the Fields application in MSC.Patran.

12 12 SOL 600 Complete the Material Models Basic material property definitions for all the components in the model have already been imported into the database from the MSC.Nastran bdf. In this section you can review the property sets for each material already imported. For the gasket, the loading/unloading curves that relate pressure and gap closure will be read into the database using the Fields application in MSC.Patran. To check the material property models: Because these properties are already in the database, this task is optional and provided so that you can follow how material properties are assigned to different structures in MSC.Patran. If you do not want to review these existing properties, skip to the section Import of Loading and Unloading Curves Using Fields, pg. 15. Step 1: On the MSC.Patran Main toolbar, click the Materials button. Step 2: From the Materials menu select the following options: Action: Select Modify. Object: Select Isotropic. Existing Materials: Select steel.

13 CHAPTER Engine Gasket Model Instructions 13 Step 3: The engine block, cylinder head, and two connecting bolts are made of steel. Review the properties on the Input Options form, then click Cancel to return to the Materials form. Step 4: In the Existing Materials area, click gasket_body_membrane.

14 SOL 600 Step 5: The gasket body is represented by a linear elastic material model. After reviewing the material properties on the Input Options form, click Cancel to return to the Materials form.

14 14 SOL 600 Step 5: The gasket body is represented by a linear elastic material model. After reviewing the material properties on the Input Options form, click Cancel to return to the Materials form. Step 6: In the Existing Materials area, click gasket_ring_membrane. Step 7: The gasket ring is also represented by a linear elastic material model. After reviewing the material properties on the Input Options form, click Cancel to return to the Materials form. Step 8: On the MSC.Patran Main toolbar, click on the Materials button to close the Materials form.

Step 2: From the Fields menu, select the following options: Action: Select Create.

15 CHAPTER Engine Gasket Model Instructions 15 Import of Loading and Unloading Curves Using Fields To read in the gasket loading and unloading data: Step 1: On the MSC.Patran Main toolbar, click the Fields button. Step 2: From the Fields menu, select the following options: Action: Select Create. Object: Select Non Spatial Method: Select Tabular Input. Field Name: Enter body_loading. Table Definition: Select Displacement (u). Click Input Data.

Step 4: From the Import/Export Field Data menu, navigate to the directory

16 16 SOL 600 Step 3: From the Non Spatial Scalar Table Data menu, click Import/Export. Step 4: From the Import/Export Field Data menu, navigate to the directory containing the body_loading.csv file. Click on the file body_loading.csv. Click Apply. This returns you to the Non Spatial Scalar Table Data menu. Click OK.

17 CHAPTER Engine Gasket Model Instructions 17 This returns you to the Fields menu. Click Apply. A field named body_loading is created. Step 5: Repeat Steps 3-10 to create fields for ring_loading, body_unloading, and ring_unloading. Step 6: On the MSC.Patran Main toolbar, click the Fields button to close the Fields form.

18 SOL 600 Complete the Gasket Element Properties With the gasket loading and unloading curves read into the database, you can assign special element properties to the gasket elements that

You also have the option of reviewing the element properties for the engine block, cylinder head, and connecting bolts that were imported from the MSC.Nastran bdf.

18 18 SOL 600 Complete the Gasket Element Properties With the gasket loading and unloading curves read into the database, you can assign special element properties to the gasket elements that incorporate the loading and unloading paths as well as additional nonlinear material parameters into the model. You also have the option of reviewing the element properties for the engine block, cylinder head, and connecting bolts that were imported from the MSC.Nastran bdf. To define the element properties for the gasket: Step 1: On the MSC.Patran Main toolbar, click the Properties button. Step 2: From the Element Properties menu, select the following options: Action: Select Modify. Object: Select 3D. Type: Select Solid. Prop. Sets by Name: Select gasket_body. Options: Select Gasket. Click Modify Properties.

Step 4: From the Select Existing Materials menu, click gasket_body_membrane.

19 CHAPTER Engine Gasket Model Instructions 19 Step 3: From the Input Properties menu, click on the Mat Prop Name icon. Step 4: From the Select Existing Materials menu, click gasket_body_membrane. This returns you to the Input Properties menu. Step 5: On the Input Properties menu, click the Loading Path icon.

20 SOL 600 Step 6: From the Select Field menu, in the Scalar Nonspatial Field list, click body_loading. This returns you to the Input Properties menu.

20 20 SOL 600 Step 6: From the Select Field menu, in the Scalar Nonspatial Field list, click body_loading. This returns you to the Input Properties menu. Step 7: On the Input Properties menu, click in the Yield Pressure field and enter In the Tensile Modulus field, enter In the Transverse Shear Modulus field, enter In the Initial Gap field, enter Click the Unloading Path 1 icon. Step 8: From the Select Field menu, in the Select Scalar Nonspatial Field list, click body_unloading. This returns you to the Input Properties form. Step 9: On the Input Properties menu, click OK. Step 10: On the Properties menu, click Apply.

21 CHAPTER Engine Gasket Model Instructions 21 Step 11: Repeat Steps 3-15 for the gasket ring and use the values listed in the following table: Field Value Material gasket_ring_membrane Loading Path ring_loading Yield Pressure 42.0 Tensile Modulus 64.0 Transverse Shear Modulus 35.0 Initial Gap 0.0 Unloading Path ring_unloading To check the element properties for the engine block and cylinder head: If you do not want to review the remaining element properties, skip to Define the Loads and Boundary Conditions, pg. 22. Step 1: In the Prop. Sets by Name area, click cylinder_head. Click Modify Properties. Click on the Mat Prop Name icon. From the Select Existing Materials list, click steel. Click OK. Click Apply. Step 2: Repeat Steps 1-4 for the left_bolt, lower_part (block), and right_bolt.

22 22 SOL 600 Define the Loads and Boundary Conditions Two sets of boundary conditions need to be applied to the model before you are ready to run the analysis. These boundary conditions define the symmetry conditions in the model and constrain the model along the bottom surface of the engine block. You also need to apply the bolt preload to the model. The load is assigned in the form of an imposed initial displacement on a cross-section of grids through each connecting bolt. This loading simulates the torquing of the bolts during the assembly process. Finally, you define the contact bodies for the analysis. To define a constraint on the bottom of the engine block: Step 1: From the Group menu, select the following options: Action: Select Post. Select Groups to Post field: Highlight prop_left_bolf, prop_lower_part, and prop_right_bolt. Click Apply. Click OK to acknowledge the caution regarding the unposting of the current group. On the MSC.Patran Main toolbar, click the Bottom view icon.

23 CHAPTER Engine Gasket Model Instructions 23 Step 2: On the MSC.Patran Main toolbar, click the Loads/BCs button. Step 3: From the Load/Boundary Conditions menu, select the following options: Action: Select Create. Object: Select Displacement. Type: Select Nodal. New Set Name: Enter FixBottom. Click Input Data... This brings up the Input Data menu.

24 SOL 600 Step 4: From the Input Data menu, select the following options: Translations <T1 T2 T3>: Enter <0,0,0> Click OK. This returns you to the Loads/Boundary Conditions menu.

24 24 SOL 600 Step 4: From the Input Data menu, select the following options: Translations <T1 T2 T3>: Enter <0,0,0> Click OK. This returns you to the Loads/Boundary Conditions menu. Step 5: From the Loads/Boundary Conditions menu, Click Select Application Region. Geometry Filter: Select FEM. Application Region: Click in the Select Nodes Field. In the viewport: Click and drag a box around the bottom nodes of the block.

To define boundary conditions along the plane of symmetry: Step 1: From the Group menu, select the following

25 CHAPTER Engine Gasket Model Instructions 25 Click Add to add these nodes to the application region Click OK. This returns you to the Loads/Boundary Conditions menu. Click Apply. To define boundary conditions along the plane of symmetry: Step 1: From the Group menu, select the following options: Action: Select Post. Select Groups to Post: Highlight all groups except default_group. Click Apply. On the MSC.Patran Main toolbar, click the Front view icon.

Action: Select Create. Object: Select Displacement. Type: Select Nodal.

26 26 SOL 600 Step 2: On the MSC.Patran Main toolbar, click the Loads/BCs button. Step 3: From the Load/Boundary Conditions menu, select the following options: Action: Select Create. Object: Select Displacement. Type: Select Nodal. New Set Name: Enter Symmetry Click Input Data... This will take you to the Input Data menu.

CHAPTER Engine Gasket Model Instructions 27 Step 4: From the Input Data menu:

This returns you to the Loads/Boundary Conditions menu.

Step 6: From the Select Application Region menu, select the following

27 CHAPTER Engine Gasket Model Instructions 27 Step 4: From the Input Data menu: Translations<T1 T2 T3> field: Enter <,0, >. Click OK. This returns you to the Loads/Boundary Conditions menu. Step 5: Click Select Application Region. Step 6: From the Select Application Region menu, select the following options: Geometry Filter: Select FEM. Application Region: click in the Select Nodes field, then in the viewport click and drag a box around the nodes in the XZ plane.

To create the bolt preload: Step 1: On the Group menu select the following options: Action: Select Post.

28 28 SOL 600 Click Add to add these nodes to the application region. Click OK. This returns you to the Loads/Boundary Conditions menu. Click Apply and then click the Loads/BCs button to close the Loads and Boundary Conditions menu. To create the bolt preload: Step 1: On the Group menu select the following options: Action: Select Post. Select Groups to Post: Highlight prop_left_bolt and prop_right_bolt. Click Apply. Click OK to acknowledge the caution regarding the unposting of the current group. Click Cancel to close the Group menu. On the MSC.Patran Main toolbar, click the Bottom view icon. Step 2: On the Utilities menu, point to Loads/BCs. Step 3: Click Bolt Preload.

Axial Bolt Load: Enter 0.175. 3D Element Faces: Click in the field.

29 CHAPTER Engine Gasket Model Instructions 29 Step 4: From the Bolt Load Creation v1.0 menu, select the following options: Target Elem Type: Select 3D. Loading Option: Select Displacement. Axial Bolt Load: Enter D Element Faces: Click in the field. Then in the viewport click and drag a box around a layer of element faces in the middle of the left bolt. Click Apply. Repeat Steps 9 and 10 for the right bolt. Click Cancel to close the Bolt Load Creation menu.

30 30 SOL 600 To define the contact bodies: In this section you define the contact bodies for the block, head, gasket, and bolts. Step 1: From the Group menu, select the following options: Action: Select Post. Select Groups to Post: Highlight prop_lower_part. Click Apply. Click Cancel to close the Group menu.

31 CHAPTER Engine Gasket Model Instructions 31 Step 2: On the MSC.Patran Main toolbar, click the Loads/BCs button. Step 3: From the Load/Boundary Conditions menu, select the following options: Action: Select Create. Object: Select Contact. Option: Select Deformable Body. Click Select Application Region...

32 32 SOL 600 Step 4: From the Select Application Region menu, select the following options: Geometry Filter, Select FEM. Application Region: Click in the Select 3D Elements field, then in the viewport click and drag a box around the entire block. Click Add. Click OK. Click Apply. Step 5: Create the deformable bodies for the gasket by repeating Steps 1 through 9 using the groups prop_gasket_body and prop_gasket_ring. Step 6: Create the deformable bodies for the cylinder head by repeating Steps 1 through 9 using the group prop_cylinder_head. Step 7: Create the deformable bodies for the bolts by repeating Steps 1 through 9 using the groups prop_left_bolt and prop_right_bolt. Step 8: Click the Loads/BCs button to close the Loads and Boundary Conditions form.

CHAPTER Engine Gasket Model Instructions 33 Define the Analysis Parameters and Output Requests At

parameters for the analysis, and request the type of output you want produced.

Step 2: From the Analysis Menu, select the following options: Action: Select Analyze.

33 CHAPTER Engine Gasket Model Instructions 33 Define the Analysis Parameters and Output Requests At this point the modeling tasks are complete and you need to define the type of analysis, the parameters for the analysis, and request the type of output you want produced. To set up the analysis: Step 1: On the MSC.Patran Main toolbar, click the Analysis button. Step 2: From the Analysis Menu, select the following options: Action: Select Analyze. Object: Select Entire Model. Method: Select Analysis Deck. Click Solution Type..., then from the Solution Type list, click Implicit Nonlinear.

.. Step 5: From the Contact Control Parameters menu, select the following

34 34 SOL 600 Step 3: Click Solution Parameters... Step 4: Click Contact Parameters... Step 5: From the Contact Control Parameters menu, select the following options: Deformable-Deformable Method: Select Double-Sided. Optimize Constraint Equations: Select check box. Click OK. Click OK. Click OK again.

CHAPTER Engine Gasket Model Instructions 35 Step 1: On

Step 2: On the Analysis menu, click Subcases.

35 CHAPTER Engine Gasket Model Instructions 35 Step 1: On the MSC.Patran Main toolbar, click the Analysis button. Step 2: On the Analysis menu, click Subcases. Step 3: From the Subcases menu, select the following options: Action: Select Create. Available Subcases: Select Default. Click Subcase Parameters... Step 4: Click Contact Table...

36 36 SOL 600. Step 5: In the Contact Matrix area, set the glue (G)/touch(T)/deactivate(blank) parameters as shown above. Clicking multiple times in each box cycles through the three possible selections. This specifies that the gasket is glued to the cylinder head and block, but not to the bolts. Click OK, click OK, then click Apply.

37 CHAPTER Engine Gasket Model Instructions 37 To define output requests and finish subcase definition: Step 1: On the Subcase menu, click Output Requests... Click Select Nodal Results... Step 2: On the Select Nodal Results menu, select the following options: Available Result Types: Select CONTACT STATUS (38) Click OK.

38 SOL 600 Step 3: Click Select Element Results... Available Result Types: Select GASKET, PRESSURE (241) and GASKET, CLOSURE (242). Click OK. Click OK. Click Apply.

38 38 SOL 600 Step 3: Click Select Element Results... Available Result Types: Select GASKET, PRESSURE (241) and GASKET, CLOSURE (242). Click OK. Click OK. Click Apply. Step 4: Click Cancel to close the Subcase menu. Step 5: Click Apply on the Analysis menu. MSC.Patran generates an updated Bulk Data file, gasket.bdf, that you will use to run the nonlinear analysis. Check in your default directly to see that gasket.bdf has been generated. Step 6: Minimize or close MSC.Patran.

CHAPTER Engine Gasket Model Instructions 39 Run the Analysis You are now ready to run the SOL 600 analysis. There are multiple ways to launch the MSC.

Nastran by double clicking on a desktop icon. To submit the analysis: Step 1: Double-click on nastranw.exe or start MSC.Nastran from a desktop icon.

39 CHAPTER Engine Gasket Model Instructions 39 Run the Analysis You are now ready to run the SOL 600 analysis. There are multiple ways to launch the MSC.Nastran analysis depending on how MSC.Nastran is installed and the availability of MSC.Patran and Analysis Manager. This section illustrates running MSC.Nastran by double clicking on a desktop icon. To submit the analysis: Step 1: Double-click on nastranw.exe or start MSC.Nastran from a desktop icon. Step 2: Select the MSC.Nastran Bulk Data file, gasket.bdf, generated from MSC.Patran, then click Open. Step 3: On the MSC.Nastran Command Information form, click Run. MSC.Nastran starts running.

40 40 SOL 600 To verify the successful completion of the analysis: Step 1: Open the MSC.Nastran output file, gasket.f06, using a text editor. Step 2: Scroll to the bottom of the file and look for the Nastran SOL 600 completion statements. *** ISHELL PROGRAM 'c:\msc.software\msc.nastran\msc20051\marc\\tools\run_marc.bat' COMPLETED *** Nastran SOL 600 completed Step 3: Close the gasket.f06 file. Step 4: Open the SOL 600 output file, gasket.marc.out, using a text editor.

41 CHAPTER Engine Gasket Model Instructions 41 Step 5: Scroll to the bottom of the file and review the run summary information. memory usage: mbyte words % of total within general memory (sizing): element storage: element stiffness matrices: solver: first part overallocation in sizing: other: allocated separately: incremental backup: solver nodal vectors: contact: tyings: transformations: kinematic boundary conditions: tables: element storage: executable and common blocks: miscellaneous total: general memory (sizing) allocated general memory (sizing) used: peak memory usage: timing information: wall time cpu time total time for input: total time for stiffness assembly: total time for stress recovery: total time for matrix solution: total time for contact: total time for output: total time for miscellaneous: total time: ************************************************************************** This is a successful completion to an MSC.Marc analysis, indicating that no additional incremental data was found and that the analysis is complete.

42 SOL 600 Access and Process the Results With the analysis complete, you will want to open the results file inside MSC.

This is accomplished in two steps, first access the results file, and then generate the results plots.

Patran Main toolbar, click the Analysis button.

42 42 SOL 600 Access and Process the Results With the analysis complete, you will want to open the results file inside MSC.Patran so that you can generate visual displays of the simulated gasket pressures and gap closure. This is accomplished in two steps, first access the results file, and then generate the results plots. To attach the results file: Open or restore MSC.Patran and the Gasket database. Step 1: On the MSC.Patran Main toolbar, click the Analysis button. Step 2: From the Analysis menu, select the following options: Action: Select Access Results. Object: Select Attach T16/T19 Method: Select Result Entities. Click Select Results File... then select the gasket.marc.t16 file generated from the MSC.Nastran analysis. Click OK, then click Apply. Click the Analysis icon to close the Analysis menu.

43 CHAPTER Engine Gasket Model Instructions 43 Step 3: On the Group menu, select the following options: Action: Select Post. Select Groups to Post: Highlight prop_gasket_body and prop_gasket_ring. Click Apply. Click Cancel to close the Group menu.

Step 2: From the Results menu, select the following options: Action: Select Create. Object: Select Fringe.

44 44 SOL 600 To create fringe plots: Step 1: On the MSC.Patran Main toolbar, click Reset Graphics icon, then click Results icon. Step 2: From the Results menu, select the following options: Action: Select Create. Object: Select Fringe. Select Result Cases: Highlight all the results cases. Select Fringe Result: Select Closure, Gasket. Animate: Select check box. Click Apply. Note: To change the range for the fringe plot, see

45 CHAPTER Engine Gasket Model Instructions 45 To create a Fringe Plot of Gasket Pressure: The Result Application menu should still be open with the Action set to Create, and the Object set to Fringe. If not, click the Results button on the MSC.Patran Main toolbar and make the Action/Object selections. Step 1: In the Select Fringe Result area, click Pressure, Gasket, then click Apply.

Step 1: From the Results menu, select the following options: Click the

46 46 SOL 600 To change the fringe plot ranges: If you wish to change the ranges for your fringe plots, follow the steps outlined below. Step 1: From the Results menu, select the following options: Click the Display Attributes icon. Click Range... Click Set Range. Click Define Range...

47 CHAPTER Engine Gasket Model Instructions 47 Step 2: From the Ranges menu, select the following options: New Range Name: Enter pressure_default_fringe. Start Value: Enter End Value: Enter Click Calculate. Click Apply. Click OK. Click Apply.

48 48 SOL 600

Linear Static Analysis of a Simply-Supported Truss

LESSON 8 Linear Static Analysis of a Simply-Supported Truss Objectives: Create a finite element model by explicitly defining node locations and element connectivities. Define a MSC/NASTRAN analysis model