Exercise 2: Weld Using a Master Connectors File and Duplicate and Reflect Connectors

In this step, you will retrieve and view the model file in HyperMesh.

1. Start HyperMesh Desktop.
2. In the User Profile dialog, set the user profile to LsDyna.
3. Open a model file by completing one of the following options:
   • Click File > Open > Model from the menu bar.
   • Click on the Standard toolbar.
4. In the Open Model dialog, open the frame_assembly_2.hm file.
5. Observe the model using various visual options available in HyperMesh (rotation, zooming, and so on).

   
   
   Figure 3.

In this step, you will create connectors to connect the right rails to each other and to the front trusses by importing a master connectors file.

1. From the menu bar, click File > Import > Connectors.
2. Set File type to Connectors.
3. In the File field, open the rails_frt_truss.mwf file.
4. Click Import.

HyperMesh imports the connectors from the file, and organizes them into a new component, CE_Locations.

Figure 4.

In this step, you will realize the connectors in the component, CE_Locations, into LS-DYNA 100 Mat100 (beam) welds.

1. In the Model Browser, Component folder, right-click on CE_Locations and select Make Current from the context menu.
2. Open the realize subpanel within the connector Spot panel by clicking Connectors > Realize > Spots from the menu bar.
3. Click location: connectors > by collector.
4. Select the CE_Locations component.

   
   
   Figure 5.

5. Click select.
6. In the tolerance = field, enter 5.
7. Set the mesh independent/mesh dependent toggle to mesh independent.
8. Click type = and select mat100.

   
   
   Figure 6.

9. Click realize.
   Note: The naming convention for these components is C_^_[id of comp 1]_[id of comp 2].
   HyperMesh realizes the selected connectors into LS-DYNA 100 Mat100 (beam) welds and organizes them into the following new component collectors:

   • C_^_1_7_BEAM_100
   • C_^_6_7_BEAM_100
   • C_^_2_7_BEAM_100
   • C_^_1_6_BEAM_100

   
   
   Figure 7.

10. Click return.

In this step, you will verify materials were automatically created when the LS-DYNA 100 Mat100 (beam) welds were created.

1. In the Model Browser, expand the Material folder.
2. Review the materials with IDs 2 through 5, that were created when the LS-DYNA 100 Mat100 (beam) welds were created.
   Note: The naming convention for the materials is M_^_[id of comp 1]_[id of comp 2]. One material is created for every two components that are connected.
3. Select one of the materials with IDs 2 through 5.
   Note: The solver keyword is set to *MAT_SPOTWELD, and the values are automatically specified for the density, Young’s Modulus, and Poisson’s Ratio parameters.
   The Entity Editor opens and displays the material's card details.

In this step, you will verify that properties were automatically created when the LS-DYNA 100 Mat100 (beam) welds were created.

1. In the Model Browser, expand the Property folder.
2. Review the properties with IDs 1 through 6, that were created when the LS-DYNA 100 Mat100 (beam) welds were created.
   Note: The naming convention for the properties is P_^_[id of comp 1]_[id of comp 2]. One property is created for every two components that are connected
3. Select one of the properties with IDs 1 through 6. The Entity Editor opens and displays the property's card details.
   Note: The solver keyword is set to *SECTION_BEAM, and the default values are specified for the property’s parameters.
   The Entity Editor opens and displays the property's card details.

In this step, you will verify that a contact was automatically created when the LS-DYNA 100 Mat100 (beam) welds were created.

1. In the Model Browser, Group folder, click C_Contact_Spotweld_1.
   Note: The solver keyword is set to *CONTACT_SPOTWELD_ID.
   The Entity Editor opens and displays the group's card details.
2. Open the Interfaces panel by clicking BCs > Assign > Interface Entities from the menu bar.
3. In the panel area, click name= and select C_Contact_Spotweld_1.
4. Click review to review the contacts.
   The contact’s master elements temporarily display blue and its slave elements temporarily display red.

   
   
   Figure 8.

5. Click return.

In this step, you will display the components Left_Rail_1 and Left_Rail_2 for elements.

In this step, you will duplicate and reflect the connectors created from the master connectors file.

1. In the Model Browser, right-click and select Create > Component from the context menu.
   A new component opens in the Entity Editor.
2. For Name, enter CE_Locations_Dup.
   Note: You do not need to assign any materials or properties.
3. Open the Reflect panel by clicking Connectors > Reflect > Connectors from the menu bar.
4. Click connectors > by collector.
5. Select the CE_Locations component.
6. Click select.
7. Click connectors > duplicate > current comp.
   HyperMesh duplicates the displayed connectors, are organizes them into the current component, CE_Locations_Dup.
8. Set the orientation selector to x-axis.
   Note: This is the axis normal to the plane of interest.
9. Reflect about the base node by clicking .
10. Click x =.
    HyperMesh activates the x =, y =, and z = fields. By default their values are 0.000, which is the base point you want to reflect about.

    
    
    Figure 9.

11. Click return.
12. Click reflect.
    HyperMesh reflects the connectors.
13. Click return.

    
    
    Figure 10.

In this step, you will update the connectors for the left rails to link them to the left rail components.

1. Open the Connector Browser by clicking View > Browsers > HyperMesh > Connector from the menu bar.
2. In the Connector Entity Browser, expand the mat 100 folder, which contains the connectors in the model with material mat100.
   Note: The reflected connectors are displayed in yellow, which indicates that they are unrealized.
3. Select all of the unrealized connectors in the list.

   
   
   Figure 11.

4. In the Entities column, right-click on the selected connectors and select Update Link from the context menu.

   
   
   Figure 12.

   The Update window opens.
5. In the Search column, set the Link Type to comps.

   
   
   Figure 13.

6. In the Search column, click the Link Select field.
7. In the panel area, click component.
8. Select the Right_Rail_1 component.
9. Click proceed.
   The Link Select field displays Right_Rail_1.
10. In the Replace column, set the Link Type to comps.
11. In the Replace column, click the Link Select field.
12. In the panel area, click component.
13. Select the Left_Rail_1 component.
14. Click proceed.
    The Link Select field displays Left_Rail_1.
15. Click Update.
    HyperMesh updates the connector's links.
16. Repeat 9 through 15, except search for the Right_Rail_2 component and replace it with the Left_Rail_2 component.
17. Ensure none of the connectors in the list of unrealized connectors are linked to the right rail components.
18. Close the Update window by clicking X next to Update.
19. Right-click on the selected connectors and select Rerealize from the context menu.
    HyperMesh realizes the connectors.

    
    
    Figure 14.

In this step, you will verify that all connectors are realized and identify the pairs of adjacent connectors.

1. Zoom in on one of the two areas where the front trusses are connected to the rail components.
   Note: In these two areas, pairs of adjacent connectors exist.
2. On the Visualization toolbar, click .
3. In the Visualization tab, click .
4. Under Color by, select Layer.
   Note: This option indicates that each of these connectors link two components. Because each pair of connectors creates a series of two weld elements, you can combine each pair into a single connector, which links the three components together.
   HyperMesh changes the connectors color to purple because under Layers, 2t (two thickness) is defined by the color purple.

In this step, you will isolate the pairs of adjacent, 2t connectors.

1. In the Model Browser, turn off the geometry display for all of the components.
2. In the Connector Browser, Link Entity Browser, while pressing Ctrl, select Front_Truss_1, Front_Truss_2, Right_Rail_1, and Left_Rail_1.
3. Right-click and select Find Between from the context menu.

   
   
   Figure 15.

   HyperMesh finds and displays the connectors between the four components you selected.

In this step, you will unrealize the selected connectors.

In the Connector Entity Browser, right-click on the selected connectors and select Unrealize from the context menu.

Figure 16.

In this step, you will save your work in HyperMesh.