Meshing and Stress Analysis of a Droop Limiter

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Meshing and Stress Analysisof a Droop Limiter

• By Geoffrey L. Ostermeyer
• Final Project
• For ME 450
• Professor Dr. Craig Weeks
• December 14, 2000

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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.

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Background

• Designed by Senior Design Team
• Used on the Electric Race Car
• Limits Rear End Lift to 3/16

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The Droop Limiter
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Parts Defined
Upper Bracket
Steel Washer
Rubber Washer -- Damper
Tie-Rod
Mounting Bolt
Tie-Rod Connector
A-Frame
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Geometry Generation

• Import IGES files from Pro-E
• Create Volumes in Ansys
• Simplified Geometries

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Pro-E Imports
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Ansys Volumes
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Simplified Geometries
From
To
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Combining Parts

• Volume Adding
• Surface Coupling
• Contact Surfaces

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Adding Volumes
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Coupling Surfaces
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Contact Surfaces
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Assembled Geometries
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Meshing

• Mapped versus Free

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Completed Mesh
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Stress Analysis Tie-Rod Connector
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Stress Analysis Upper Bracket
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Stress Analysis Washer/Tie-Rod Weld
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Damper Design
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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 Youngs Modulus of approximately 30,000
  psi (Polyester Elastomer).
• A more conventional rubber may be used with a
  smaller washer thickness.