# OS-SL-T: 1000 Nonlinear Analysis of Rubber Ring

This tutorial demonstrates the creation of finite elements on a given CAD geometry of a rubber ring.

Before you begin, copy the file(s) used in this tutorial to your working directory.

Application of boundary conditions and a finite element analysis of the problem are explained. Post-processing tools are used to determine stress developed during crushing and sliding of a rubber ring.

The following exercises are included:
• Set up the problem in SimLab
• Apply Loads and Boundary Conditions
• Solve the job
• View the results

Launch SimLab.

## Import the Model

1. From the menu bar, click File > Import > Database.
An Import File dialog opens.
2. Select the Rubber_Ring.gda file you saved to your working directory from the Rubber_Ring.zip file.
3. Click Open.
The Rubber_Ring.gda database is loaded into SimLab. The .gda file only contains geometric data.

## Create Solution

1. From the Solutions ribbon, Physics group, click the Structural tool.
A Create Solution dialog opens.
2. In the Create Solution dialog, define the following options:
1. For Name, enter Rubber_Ring
2. For Solver, select OptiStruct.
3. For Solution type, select Non Linear Static.
4. For Select bodies, select all the bodies from the Model Browser and click OK.
In the Solutions tab of the Model Browser, an OptiStruct – Non Linear Static solution with the selected bodies is created.

## Set up the Model

### Import Material

1. In the Property tab of the Model Browser, right-click on Materials and select Import from the context menu.
2. In the Open dialog, select the Rubber_Material.xml file and click Open.
The Rubber_Material and respective data tables is added to the current materials list.
3. From the Analysis ribbon, Property group, click the Material tool.
A Material dialog opens.
4. Enter the values, as shown below and click OK.

### Create Properties

1. From the Analysis ribbon, Property group, click the Property tool.
A Analysis Property dialog opens.
2. In the Analysis Property dialog, enter the values shown below.
3. Assign property to Ring.
1. In the Assembly tab of the Model Browser, select Ring.
2. In the Analysis Property dialog, click Apply.
4. Create a property for Top and Bottom Ends.
1. Enter the values in the Analysis Property dialog, as shown below.
2. In the Assembly tab of the Model Browser, select Top & Bottom Ends.
3. In the Analysis Property dialog, click Apply.
5. Create property for RBEs.
1. Enter the values in the Analysis Property dialog, as shown below.
2. In the Assembly tab of the Model Browser, select Top RBE and End RBE.
3. In the Analysis Property dialog, click Apply.
The created Materials and Properties are listed in the Property tab of the Model Browser.

## Set Up Loads and Constraints

### Create Contacts

Contacts are created between the Ring and End Faces to simulate the Compressing and Sliding action of the ring against the Top and Bottom Ends.

1. From the Analysis ribbon, Loads and Constraints group, click the Contact tool.
A Define Contact dialog opens.
2. In the Define Contact dialog, set the parameters as shown below.

3. In the Define Contact dialog, select the line edit field for Main faces.
The line edit field is highlighted.
4. In the modeling window, select the Top End faces.
5. In the Define Contact dialog, select the line edit field for Secondary faces.
The line edit field is highlighted.
6. In the modeling window, select the Outer Ring faces.
7. In the Define Contact dialog, click Apply.
The contact will be created and added to the Solution tab in the Model Browser.
8. Create a contact between Bottom End & Ring.
1. Set the following parameters in the Define Contact dialog, as shown below.
2. In the Define Contact dialog, select the line edit field for Main faces.
The line edit field is highlighted.
3. In the modeling window, select the Bottom End faces.
4. In the Define Contact dialog, select the line edit field for Secondary faces.
The line edit field is highlighted.
5. In the modeling window, select the outer Ring faces.
6. In the Define Contact dialog, click Apply.
The created contact is listed in the Solution tab of the Model Browser.
9. Ceate a contact for the inner faces of the Ring.
1. Set the following parameters in the Define Contact dialog, as shown below.
2. In the Define Contact dialog, select the line edit field for Main faces.
The line edit field is highlighted.
3. In the modeling window, select the top semi-circular inner face of the ring.
4. In the Define Contact dialog, select the line edit field for Secondary faces.
The line edit field is highlighted.
5. In the modeling window, select the bottom semi-circular inner face of the ring.
6. In the Define Contact dialog, click OK.
The contact will be created and added to the Solution tab in the Model Browser.

1. In the Model Browser, click the Solutions tab.
2. In the Solutions tab, right-click Rubber Ring and select Define using Load case from the context menu.
A Non Linear Static loadcase type is created.
The Loads and Constraints pertaining to simulate the Compressing action on the Ring will be added in the Ring_Compression loadcase.
2. Right-click on LoadCase2, select Rename from the context menu, and enter Ring_Sliding.
3. Verify Type is set to Non Linear Static.

### Define Constraints

1. From the Solutions tab of the Model Browser, right-click on the Ring_Compression loadcase and select Set Current from the context menu.
2. From the Assembly tab of the Model Browser, select Ring.
The Ring body is highlighted in the modeling window.
3. Right-click in the modeling window and select Isolate from the context menu.
The Ring body is isolated in the modeling window.
4. Right-click in the modeling window and change the selection filter to Face.
5. From the Analysis ribbon, Loads and Constraints group, click the Constraints tool.
6. From the secondary tool set, select the Fixed tool.
The Fixed Constraint dialog opens.
7. In the Fixed Constraint dialog, set the Axes as shown below.
8. In the modeling window, select all four faces of the Ring body and click Apply in the Fixed Constraint dialog.
9. Right-click in the modeling window and change the selection filter to Node.
10. In the modeling window, select the Nodes on the front and back sides of the Ring body, as shown below.
11. In the Fixed Constraint dialog, set the Axes as shown below and click Apply.
12. Right-click in the modeling window and select Redisplay Model from the context menu.
All bodies display in the modeling window.
13. Right-click in the modeling window and change the selection filter to RBE Node.
14. In the modeling window, select the RBE Main Node of the End RBE, as shown below.
15. In the Fixed Constraint dialog, set the Axes as shown below and click OK.

### Apply Enforced Displacement

1. From the Analysis ribbon, Loads and Constraints group, click the Constraints tool.
2. From the secondary tool set, select the Enforced tool.
The Enforced Constraint dialog opens.
3. Right-click in the modeling window and change the selection filter to RBE Node.
4. In the modeling window, select the RBE Main Node of the Top RBE, as shown below.
5. In the Enforced Constraint dialog, define the parameters as shown below and click OK.
1. In the Solutions tab of the Model Browser, right-click on the Ring_Sliding loadcase and select Set Current from the context menu.
2. Right-click the Ring_Z constraint under Ring_Compression, and select Add to current Loadcase from the context menu.
3. Right-click the Bottom_End constraint under Ring_Compression, and select Add to current Loadcase from the context menu.
7. Repeat steps 1 through 3.
8. In the Enforced Constraint dialog, define the parameters as shown below.
9. In the modeling window, select the RBE Main Node of the Top RBE, as shown below.
10. In the Enforced Constraint dialog, click OK.
The Enforced Displacement for generating the sliding force is added to the current loadcase.

1. In the Solutions tab of the Model Browser, right-click the Ring_Compression loadcase and select Loadcase Parameters from the context menu.
2. In the Loadcase Parameters dialog, set the values as shown below and click OK.
1. In the Solutions tab of the Model Browser, right-click the Ring_Sliding loadcase and select Loadcase Parameters from the context menu.
2. In the Loadcase Parameters dialog, set the values as shown below and click OK.
The Loadcase Parameters are added in the Solutions tab of the Model Browser.

### Create Solution Parameters and Output Requests

1. In the Solutions tab of the Model Browser, right-click on the Rubber_Ring solution and select Solution Parameters from the context menu.
The Solution Parameters dialog opens.
2. In the Solution Parameters dialog, set the values as shown below and click OK.
3. In the Solutions tab of the Model Browser, right-click on the Rubber_Ring solution and select Result Request from the context menu.
The Result Request dialog opens.
4. In the Result Request dialog, set the values as shown below and click OK.
The Solution Parameters and Output Requests are added to the Rubber_Ring solution.

## Solve and View Results

### Solve the Solution

1. In the Solutions tab of the Model Browser, right-click on Results and click Update.
The solution begins to solve. After solving, the results are automatically loaded back into the database. After the solving is completed, the results are loaded into SimLab and the results for the final loadcase are displayed by default.
2. In the Solutions tab of the Model Browser, right-click on Results under the Ring_Compression loadcase and click Display.
The results for the Ring_Compression loadcase are displayed.
3. Optional: Change the Results components using the Results panel at the top of the modeling window and animate the results using the Animation panel at the bottom of the modeling window.
4. In the Solutions tab of the Model Browser, right-click on Results under the Ring_Sliding loadcase and click Display.
The results for the Ring_Sliding loadcase are displayed.