This content is not included in
your SAE MOBILUS subscription, or you are not logged in.
The Effects of Local Spring Perch Flexibility on Suspension Geometry of a Winston Cup Race Car
Annotation ability available
Sector:
Language:
English
Abstract
In order to achieve predictable handling of a race car, local mounts connecting suspension components to the chassis should be sufficiently rigid to minimize unwanted local deflection which may adversely affect suspension geometry. In this work, the effects of local chassis flexibility of the spring perch on roll stiffness, tire camber change, and steer angle change are determined from a finite element model (FEM) of a Winston Cup race car. Details such as side gussets, supporting brackets, and local curvature of the frame rail spring pocket are included in a shell model of the spring perch. The local shell model of the spring perch is integrated with the global finite element stiffness model of the chassis and suspension consisting of an assembly of beam and shell elements.
A parametric study on the effects of thickness changes for seven different areas of the spring perch has been performed. Tire camber change, steer angle change, and chassis roll stiffness are plotted as a function of thickness variation for each of the seven perch areas. Results indicate that the surface with the most adverse affects on torsional stiffness, roll stiffness, and camber changes, resulting from reduced thickness, is the principal spring support plate. Stiffness increases may be achieved by increasing the thickness of the spring plate, spring pocket, and frame rail box beam, but the greatest benefits result from otherwise fortifying the spring pocket and box beam. The frame rail box beam and spring pocket exert tremendous influence on steer angle behavior, and can increase roll stiffness and minimize camber change if properly reinforced.
Recommended Content
Technical Paper | Design of a Winston Cup Chassis for Torsional Stiffness |
Technical Paper | Finite Element Analysis of a NASCAR Winston Cup Stock Car |
Technical Paper | Vehicle Chassis/Suspension Dynamics Analysis - Finite Element Model vs. Rigid Body Model |
Authors
Citation
Thompson, L., Herrick, G., and Law, E., "The Effects of Local Spring Perch Flexibility on Suspension Geometry of a Winston Cup Race Car," SAE Technical Paper 983032, 1998, https://doi.org/10.4271/983032.Also In
References
- Integrated Design Engineering Analysis Software Master Series 5 Computer Software Structural Dynamics Research Corporation 1997
- Keiner, Henning “Static Structural Analysis of a Winston Cup Chassis under a Torsional Load” Department of Mechanical Engineering Clemson University 1995
- Crawford John “Finite Element Analysis of a NASCAR Winston Cup Stock Car” SAE Paper No. 942527 , SAE Motorsports Engineering Conference Detroit, MI December 1994
- Raju, Srikanth “Design and Analysis of a Winston Cup Stock Car Chassis for Torsional Stiffness using the Finite Element Method” Master of Science Thesis, Department of Mechanical Engineering Clemson University August 1998
- Lampert, Jon K. “Design and Analysis of a Twist Fixture to measure the Torsional Stiffness of a Winston Cup Chassis” Master of Science Thesis, Department of Mechanical Engineering Clemson University August 1998
- Milliken, Douglas L. Milliken William F. Race Car Vehicle Dynamics Pennsylvania SAE Publications Group 1995
- Day, Kent A. Doctor of Philosophy Dissertation Department of Mechanical Engineering Clemson University
- Herrick, Gregory, P. “The Effects of Spring Perch Flexibility on Front Suspension Geometry and Roll Stiffness of a Winston Cup Stock Car Using the Finite Element Method” Master of Science Thesis. Department of Mechanical Engineering Clemson University August 1998
- Soni, Pipasu H. “Effects of Chassis Flexibility on Roll Stiffness of a Winston Cup Stock Car Using the Finite Element Method” Master of Science Thesis. Department of Mechanical Engineering Clemson University May 1998