2. Meshing and Stress Analysis of a “Droop” Limiter By: Geoffrey L. Ostermeyer Final Project For: ME 450 Professor: Dr. Craig Weeks December 14, 2000

3. Problem Statement Model, mesh, and analyze “Droop” Limiter using Ansys for IUPUI Electric Race Car Team. Analysis should include determination of stress concentrations and damper design.

4. Background Designed by Senior Design Team Used on the Electric Race Car Limits Rear End Lift to 3/16”

5. The Droop Limiter

6. Parts – Defined Steel Washer Rubber Washer -- Damper Upper Bracket Tie-Rod Connector A-Frame Mounting Bolt

7. Geometry Generation  Import IGES files from Pro-E  Create Volumes in Ansys  Simplified Geometries

8. Pro-E Imports

9. Ansys Volumes

10. Simplified Geometries From To

11. Combining Parts  Volume Adding  Surface Coupling  Contact Surfaces

12. Adding Volumes

13. Coupling Surfaces

14. Contact Surfaces

15. Assembled Geometries

16. Meshing Mapped versus Free

17. Completed Mesh

18. Stress Analysis – Tie-Rod Connector

19. Stress Analysis – Upper Bracket

20. Stress Analysis – Washer/Tie-Rod Weld

21. Damper Design

22. Conclusions  Stress Concentration on Tie-Rod Connector is not expected to be a problem.  Upper bracket and washer/tie-rod weld stress concentrations are potential hazards.  At current dimensions, the damper would require a Young’s Modulus of approximately 30,000 psi (Polyester Elastomer).  A more conventional rubber may be used with a smaller washer thickness.