Comparision of the base setup simulation results and different kinematic condition simulation results using Hypermesh Hypercrash and Radioss

Objective:

To generate mesh for the bumper system with mesh size=6mm and also compare the base setup simulation results and different kinematic condition simulation results for given crush tube files.

Case set up and Execution:

Bumper System:

1. Open the Bumper_system.hm file.
2. Create mesh with size=6mm, one face at a time.
3. Check for the element quality.

Crush Tube:

Case 1:

1. Open the Crush_tube_0000.rad file in Hypercrash
2. No changes are made and the model is run as it is.
3. After the run we obtain the .h3d file which is opened in Hyperview and we plot the graphs using .T01 file in Hypergraph.

Case 2:

For this, we change the value of Inacti=6.

1. Open the Crush_tube_0000.rad file in Hypercrash.
2. In contact interface surface section, in Type 7 contact change the Inacti value to 6
3. Export the file and run to obtain the .h3d and .T01 file for animation in Hyperview and plotting graphs in Hypergraph respectively.

Case 3:

Now we create Type 11 contact.

1. Open the Crush_tube_0000.rad file in Hypercrash.

2. Now the recommended values mentioned in the video are used for Type 7 contact.

3. As explained in video we create the Type 11 contact.

4. Now, export the file and run to obtain the .h3d and .T01 file for animation in Hyperview and plotting graphs in Hypergraph respectively.

Case 4:

Both notches and boundary conditions on the node are removed.

1. Open the Crush_tube_0000.rad file in Hypercrash.

2. Remove the notches using the Align Node option.

3. The Type 7 and Type 11 contacts are used similar to case 3.

4. Boundary conditions are removed.

5. Export the file and run to obtain the .h3d and .T01 file for animation in Hyperview and plotting graphs in Hypergraph respectively.

Case 5:

Create a notch in the middle.

1. Open the Crush_tube_0000.rad file in Hypercrash.

2. Create a notch in the middle of the model using Align Nodes option.

3. Remove all the notches present in previous case 4.

4. The Type 7 & 11 contacts are not changed and boundary conditions are also deleted as in case 4.

5. Export the file and run to obtain the .h3d and .T01 file for animation in Hyperview and plotting graphs in Hypergraph respectively.

Case 6:

Now all the previous notches are removed and 2 new notches on opposing faces are created.

1. Open the Crush_tube_0000.rad file in Hypercrash.

2. Create 2 new notches on opposing faces using Align Nodes option.

3. Remove all the notches present in the previous case 5.

4. The Type 7 & 11 contacts are not changed and boundary conditions are also deleted as in case 5.

5. Export the file and run to obtain the .h3d and .T01 file for animation in Hyperview and plotting graphs in Hypergraph respectively.

Result and Conclusion:

The following table shows the results that were obtained:

1. In case 2, changing Inacti value to 6 had no change in the result when compared with case 1.
2. By changing the Type 7 values and adding Type 11 contact interface the contact force and Rwall forces increased.
3. In all the cases, the crush tube deformation started at the notch.
4. In case 4 when all the notches were removed along with boundary conditions there was a decrease in contact, internal energy, and normal Rwall forces.
5. By re-adding the notch there was an increase in contact and tangent Rwall forces.
6.  By having only 2 notches on opposing faces we can see that there is an increase in contact, internal energy, and normal Rwall forces.

Thus, all the points mentioned in the objective are successfully carried out using Hypermesh, Hypercrash, and Radioss.