Goal

Review past simulation files used to pass VDR (primarily MS14, but could look at MS12) and compare them to the current simulation.

If time permits, insert geometry of current chassis into past simulation file/setup to see if results stay the same.

Folder Path: D:\Users\Roo\Documents\GrabCAD\MSXIV sims\MS-CHASSIS

File Names:

1. 2019-11-30_FINAL.wbpj - finalized project file with the structural BP.

2. 2020-03-31.wbpj - project file with the BP being considered less structural (catamaran tubes added).

3. August25_Rev5.1.wbpj - Current iterative solution with reinforcements and non-structural BP

Outline of Settings:

• Project Workbench

• Engineering data

• Geometry (Spaceclaim)

• Model

• ACP Pre

• Static Structural (Specific Case Models: B-pillar, Side 60, Top 30)

Comparison of Simulation Settings

Conclusions

Project Workbench - naming convention varies, but the set-up remains similar (other than the fact that File 1 has ACP Post for each case)

Engineering Data - This info either uses default values from Ansys or is copied over from previous simulation files (i.e. are the same). (Focusing on 4130 steel and structural steel for now)

*Geometry - This is the main area in which our current set-up differs from previous files.

• removal of BP and addition of reinforcements

• removal of rear passengers mass

• currently seeing 97 beam profiles rather than 6 (likely due to duplicates, but should sort this out)

* Model - Settings are similar except for the following:

• Connections (currently have about half the number of contacts compared to previous files)

ACP Pre - Files appear to have similar settings. (wasn’t looked at too closely)

Static structural - These settings (acceleration and fixed support) are the same as in previous files.

Additional Investigation of Stress Results

Originally, a good check to see if the simulation settings were appropriate was to insert the current chassis geometry into a previous simulation file.

This is deemed to take too much time because you would have to re-insert and re-edit a geometry, and re-create the contacts.

Instead, the old project file is used and the bottom panel (BP) is suppressed.
Consequently, this also turns of the Battery Box (100 kg) and 4 passengers (80 kg) mass points each.
So, keep this in mind when you view the results.

Procedures used: Suppress BP → Click Solve. Solutions were checked for reasonable deformation.

Open

Past Simulation Project Used: 2020-03-31.wbpj

Folder Path: D:\Users\Roo\Documents\GrabCAD\MSXIV sims\MS-CHASSIS

Previous to suppressing the BP, this project file had all stresses below 435 MPa. Maximum combined stress was about 280 MPa which suits the criteria of FS of 1.5 from yield strength of 4130 chromoly steel (the chassis tube material).

Latest Simulation Project: August 25_Rev 5.1.wbpj

Folder Path: D:\Users\Roo\Documents\GrabCAD\MSXIV sims\MS-CHASSIS\Spring 2021 Reinforcement Sims

Keep in mind, this latest iteration has the 2 rear passenger masses turned off.
It also has multiple reinforcements.

Iterative Solution Documentation - Mechanical - Confluence (atlassian.net)

Conclusion

Turning off the BP drastically increased stresses in previous simulations.
This means that it can be concluded that the results we see in the newer simulations (where the BP is removed and reinforcements are added) are realistic and are not due to deviation of simulation setup procedures.

This evidence supports that:

• the results we are seeing are accurate

• the current simulations are not largely deviating from the MIDSUN simulation procedures