doorseal_instructions.pdf

Loading ...
Global Do...
News & Politics
The 2005 New Template
 
Rubber Door Seal Modeling 
Instructions
Demonstrated:
! Set up the Model Database     2
! Create the Rubber Seal Model     4
! Define the Door and Door Closing Motion     20
! Run the Analysis and Review Results     29

SOL 600
  
2
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 Rubber_seal.db and then click OK.

3
CHAPTER
Rubber Door Seal Modeling Instructions
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.

SOL 600
  
4
Create the Rubber Seal Model
To run the MSC.Patran session file:
A MSC.Patran session file is a recording of the keystrokes and menu selections from a prior MSC.Patran 
session. The session file can be used to recreate a model and complete the simulation tasks just as they 
had been complete in the prior session. In this problem you will use a session file to import some basic 
geometric entities.
Step 1: On the File menu, click Session, then click Play.
Step 2: Navigate to the directory containing the rubber-seal.ses file.
Step 3: Click once on rubber-seal.ses and click Apply.

5
CHAPTER
Rubber Door Seal Modeling Instructions
To create a single curve for a rigid body:
Step 1: On the MSC.Patran Main toolbar, click 
the Geometry button.
Step 2: From the Geometry menu, select the 
following options:
• Action: Select Create.
• Object: Select Curve.
• Method: Select Chain.
• Curve ID List: Pick curves 2, 3, and 4 
(To select multiple curves, hold down 
the Shift Key when selecting the 
curves.)
• Click Apply.
• When asked “Do you wish to delete the constituent curve?” select Yes.

SOL 600
  
6
To mesh the seal:
Complete the following steps to mesh only the top part of the model.
Step 1: On the MSC.Patran Main toolbar, click the 
Elements button. 
Step 2: From the Finite Elements menu, select the 
following options:
• Action: Select Create.
• Object: Select Mesh.
• Type: Select Surface.
• Select the Surface or Face icon.
• Pick the three surfaces, Surface 1:3.
• Uncheck the Automatic Calculation 
box.
• Value: Enter 0.015.
• Click Apply.

7
CHAPTER
Rubber Door Seal Modeling Instructions


SOL 600
  
8
To mesh the bottom part of the model, use Paver as the Mesher.
Step 1: From the Finite Elements menu, select 
the following options:
• Mesher: Select Paver.
• Select the Surface or Face icon.
• Pick Surface 4.
• Uncheck the Automatic Calculation 
box.
• Value: Enter 0.015.
• Click Apply.

9
CHAPTER
Rubber Door Seal Modeling Instructions
To Equivalence any duplicate nodes created during meshing:
Equivalence any duplicate nodes created during meshing. This process will delete all the overlapped 
nodes (where the pink circles are), and have only one node left. 
Step 1: From the Finite Elements menu, select the following options:
• Action: Select Equivalence.
• Object: Select All.
• Method: Select Tolerance Cube.
• Equivalencing Tolerance: Enter 0.005.
• Click Apply. 
Equivalence any duplicate nodes created 
during meshing. This process will delete all 
the overlapped nodes (where the pink circles 
are), and have only one node left. 

SOL 600
  
10
To verify the elements’ normals:
Since this is a 2D solid model, all element normals must point in the positive Z direction. Verify the 
elements’ normals, and correct those whose normals point the wrong direction.
Step 1: From the Finite Elements menu, select the following options:
• Action: Select Verify.
• Object: Select Element.
• Test: Select Normals.
• Display Control: Click Draw Normal 
Vectors.
• Click Apply.
• Click the Iso 1 View button.
• Test Control: Click Reverse 
Elements.
• Guiding Element: Enter Elm 314.
• Click Apply.

11
CHAPTER
Rubber Door Seal Modeling Instructions
To create a node for future reference:
Step 1: From the Finite Elements menu, select 
the following options:
• Action: Select Create.
• Object: Select Node.
• Method: Select Edit.
• Node ID List: Enter 9999.
• Uncheck the Auto Execute box.
• Node Location List: Enter [0  0  0].
• Select the Front View icon.
• Click Apply.
Note:  
To turn off the labels on your model, 
click on the Cycle Show labels icon.

SOL 600
  
12
Location of the Node 9999.

13
CHAPTER
Rubber Door Seal Modeling Instructions
To define the rubber material:
The rubber material of the seal is modeled using the 
Mooney-Rivlin hyperelastic material model.
Step 1: On the MSC.Patran Main toolbar, click 
the Materials button. 
Step 2: From the Materials menu, select the 
following options:
• Action: Select Create.
• Object: Select Isotropic.
• Method: Select Manual Input.
• Material Name: Enter rubber.
• Click Input Properties... This will 
bring up the Input Options menu.

SOL 600
  
14
Step 3: From the Input Options menu, select the following options:
• Constitutive 
Model: Select 
Hyperelastic.
• Compressibility: 
Select Nearly 
Incompressible.
• Data Type: 
Select 
Coefficients.
• Strain Energy 
Potential: Select 
Mooney-Rivlin 
MATHP.
• Order of 
Polynomial: 
Enter 1.
• Distortional 
Def. 
Coef. A10 =: 
Enter 80.
• Distortional 
Def. 
Coef. A01 =: 
Enter 20.
• Click OK.
• Click Apply. 

15
CHAPTER
Rubber Door Seal Modeling Instructions
To define the element properties:
In this step, you define the properties for the rubber seal elements. 2D solid plane strain elements are 
used with a hyperelastic element formulation. The rubber material defined in the previous step is 
assigned to these elements.
Step 1: On the MSC.Patran Main toolbar, click the Properties button. 

SOL 600
  
16
Step 2: From the Element Properties menu, select 
the following options:
• Action: Select Create.
• Object: Select 2D. 
• Type: Select 2D Solid.
• Property Set Name, Enter seal.
• Options: Select Plane Strain, and 
Hyperelastic Formulation.
• Click Input Properties.... This will 
bring up the Input Properties menu.

17
CHAPTER
Rubber Door Seal Modeling Instructions
Step 3: From the Input Properties menu, select the Mat Prop Name. This will bring up the Select 
Material menu.
Step 4: From the Select Material menu, select rubber. Your selection, rubber, is automatically 
placed in the Material Name field in the Input Properties menu as shown below: 
Step 5: Click OK.

SOL 600
  
18
To define the elements in the rubber seal:
In this exercise, you will be defining the element 
properties for the rubber seal.The seal will be 
modeled using a 2D Solid (Plane Strain) 
Hyperelastic element formulation. The rubber 
material will be assigned to this property. 
Step 1: Click in the Select Members box, under 
the Application Region.
Step 2: Select the Surface or Face icon. 
Step 3: Select all four surfaces of your model.
Step 4: Click Add. This adds the four surfaces to 
the Application Region.
Step 5: Click Apply.

19
CHAPTER
Rubber Door Seal Modeling Instructions


SOL 600
  
20
Define the Door and Door Closing Motion
To create the rigid contact object:
In this step you will model the door as a rigid body 
and assign a displacement vector to the door to 
simulate the door closing against the rubber seal. 
Step 1: On the MSC.Patran Main toolbar, click the 
Loads/BCs button. 
Step 1: From the Load/Boundary Conditions 
menu, select the following options:
• Action: Select Create.
• Object: Select Contact.
• Type: Select Element Uniform.
• Option: Select Rigid Body.
• New Set Name: Enter DOOR.
• Target Element Type: Select 1D. 
• Click Input Data... This will bring up 
the Input Data menu.

21
CHAPTER
Rubber Door Seal Modeling Instructions
Step 2: From the Input Data menu, select the 
following options:
• Motion Control: Select Position.
• Displacement (vector): Enter
<-0.1, -0.7, 0.>. 
• Rotation Reference Point: Enter 
Node 9999.
See next page for location of this node. 
• Click OK. This will bring you back to 
the Load/Boundary Conditions 
menu.
Step 3: Click Select Application Region.... 
This will bring up the Select Application Region menu.
Note:  
You do not need to enter a node if no 
rotation of the rigid surface is to be 
used. You are entering a node so you 
are able to later experiment with 
forcing a rotation of the rigid surface; 
therefore, if you wish, ignore this 
instruction for now.

SOL 600
  
22
Step 4: From the Select Application Region menu, select the following options:
• Geometry Fitter Select Geometry.
• Select Curve 5 on your model.
• Click Add.
• Click OK.
• Click Apply.
 5
Curve 5

23
CHAPTER
Rubber Door Seal Modeling Instructions
The Apply action actually saves the rigid contact body in 
the MSC.Patran database.You should then see the contact 
(pink) markers in the viewport and the name of the object, 
DOOR, in the Existing Sets panel.
The rigid contact markers point in the direction toward the inside of the rigid body - think of them as 
tickmarks representing a wall. 
Note:  
If the rigid contact markers (pink tickmarks) appear on the wrong side of the line, Click 
Undo and Select Flip Contact Side in the Input Data menu and Click OK.

SOL 600
  
24
To see the motion of the rigid body:
Step 1: From the Load/Boundary Conditions menu, 
Click Preview Motion... This will bring up the 
Rigid Body Motion Preview menu.
Step 2: From the Existing Sets panel: Select DOOR.
Step 3: Click Preview Motion...

25
CHAPTER
Rubber Door Seal Modeling Instructions
To create the deformable contact object:
Step 1: From the Load/Boundary Conditions menu, 
select the following options:
• Action: Select Create.
• Object: Select Contact.
• Type: Select Element Uniform.
• Option: Select Deformable Body.
• New Set Name: Enter rubber.
• Target Element Type: Select 2D. 
• Click Select Application Region....
Step 2: From the Select Application Region menu 
select the following options:
• Geometry Fitter: Choose Geometry.
• Application Region: Click in the Select 
Surfaces box. Holding down the Shift key, 
Select all four surfaces on the model.
• Click Add.
• Click OK.

SOL 600
  
26
• Click Apply. You should now see the contact markers (pink circles) in viewport.

27
CHAPTER
Rubber Door Seal Modeling Instructions
To create the Boundary Condition fixing bottom of rubber seal:
Step 1: From the Load/Boundary Conditions 
menu, select the following options:
• Action: Select Create.
• Object: Select Displacement.
• Type: Select Nodal.
• New Set Name: Enter Base fix.
• Click Input Data....
Step 2: From the Input Data menu, select the 
following options:
• Translations: Enter <0,0, >.
• Rotations: Enter < , , >.
• Click OK.

SOL 600
  
28
• Click on Select Application Region.... 
• On the Select Application Region menu 
select Geometry Fitter: Select 
Geometry.
• Application Region: Click in the Select 
Geometry Entities: Select the bottom 
edge of the surface using the Curve or 
Edge icon.
• Click Add.
• Click OK.
• Click Apply.

29
CHAPTER
Rubber Door Seal Modeling Instructions
Run the Analysis and Review Results
To set up and launch the analysis:
Step 1: On the MSC.Patran Main toolbar, click the 
Analysis button. 
Step 1: From the Load/Boundary Conditions menu, 
select the following options:
• Analysis: Select Analyze.
• Object: Select Entire Model.
• Method: Select Full Run.
• Job Name: Enter rubber_job1.
• New Set Name: Enter door.
• Click Solution Type.... This will bring up 
the Solution Type menu.

SOL 600
  
30
Step 2: Solution Type: Select Implicit Nonlinear. 
Step 3: Click OK. This will bring up the Analysis 
menu.
Step 4: Click Subcases… This will bring up the Subcases menu.

31
CHAPTER
Rubber Door Seal Modeling Instructions
Step 5: Subcase Name: Enter close_door.
Step 6: Click Subcase Parameters... This will 
bring up the Static Solution 
Parameters menu.
• Linearity: Select Nonlinear.
• Nonlinear Geometric Effects: 
Select Large Displacement/ Large 
Strains.
Note:  
Click Contact Table to take a look at this table. No changes will be made here. 
Note that the rubber seal can make contact with itself and the rigid body. The rigid body 
on the other hand, cannot contact itself. 
Click OK to close this table.

SOL 600
  
32
• Click OK to close the Static Solution Parameters menu.

33
CHAPTER
Rubber Door Seal Modeling Instructions
Step 7: On the Subcases menu, Click Output Requests...
Step 8: On the Output Requests menu, 
Click Select Element Results...
Step 9: On the Select Element Results menu, in the Available Results Types field: Select the post 
codes STRAIN, TOTAL COMPONENTS (301) and STRESS, COMPONENTS 311. 
Unselect any other post codes in the Selected Result Types field by clicking on them.
• Click OK twice, one on the Selected Element Results menu and the other on the Output 
Request menu.
• Click Apply.
• Click Cancel.

SOL 600
  
34
Step 10: From the Analysis menu, Click on Subcase 
Select... This will bring up the Subcase Select 
menu where you will select the following 
options:
• Subcases For Solution Sequence: 600: 
Select close_door.
• Subcases Selected: Select Default.
• Click OK.
Step 11: From the Analysis menu, Click Apply.

35
CHAPTER
Rubber Door Seal Modeling Instructions
To read (Attach) results:
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 Results Entities.
• Available Jobs: Select rubber_job1.
• Click Apply. This will automatically attach 
rubber_job1.marc.t16.
Note:  If you need to select a different T16 file, you need 
to click the Select Results File... This will bring 
up the Select Results menu where you can 
navigate and select the file.

SOL 600
  
36
To create the Postprocess results:
Step 1: On the MSC.Patran Main toolbar, click the 
Results button. 
Step 2: From the Results menu, select the following 
options:
• Action: Select Create.
• Object: Select Quick Plot.
• Select Result Cases: Select the last case.
• Select Fringe Result: Select Strain, Total.
• Quantity: Select von Mises.
• Select Deformation Result. Select 
Displacement, Translation.
• Click Apply.

37
CHAPTER
Rubber Door Seal Modeling Instructions


SOL 600
  
38
To visualize the results:
Step 1: From the Results menu, select the 
following options:
• Action: Select Create.
• Object: Select Quick Plot.
• Click Select Result icon.
•
In the Select Case(s) window, 
click the first result and drag to 
the last result to select all 
available results cases.
• Select Fringe Result: Select 
Strain, Total.
• Quantity: Select von Mises.
• Select Deformation Result: 
Select Displacement, 
Translation.
• Click Apply to see a “pseudo-
animation” of the results as they 
are displayed. 
• Click Apply again to repeat the 
animation.

39
CHAPTER
Rubber Door Seal Modeling Instructions


SOL 600
  
40