Aerodynamic study of Jeff Gordon’s NASCAR 2000
Christina Koehly Michael Schneider
Indiana University - Purdue University Indianapolis, USA
Internship Students from Germany
Berufsakademie (University of Cooperative Education) Karlsruhe, Mannheim, Germany
Faculty Advisor: Professor H. U. Akay Department of Mechanical Engineering, IUPUI March 2001
Jeff Gordon’s NASCAR
(BRICKYARD 400, AUGUST 5th 2000)
Indianapolis Motor Speedway
Home of Brickyard 400
Project Objective
• Use Finite Element code ANSYS/FLOTRAN and Finite Volume code StarCD
– Examination of aerodynamic behavior – Comparison of Velocity Magnitude and Static Pressure
• Decision of which program give better results
THE PROJECT TEAM AT WORK!
Theory: Assumptions
• Steady State • Newtonian Fluid • Turbulent Model
Property
Density Dynamic Viscosity Car Length 1.205 1.81E-5 5.195843
• Incompressible Fluid • Adiabatic Conditions
Value Units
kg/m3 Ns/m2 m
Reynolds Number
1. Free Stream Velocity
2. Free Stream Velocity 3. Free Stream Velocity
35
70 100
m/s
m/s m/s
12.17E+06
24.21E+06 34.59E+06
ANSYS/FLOTRAN and StarCD Procedure
• • • • • • • Define the problem Define Keypoints Make Areas from Keypoints Create the Finite Element Mesh Set Boundary Conditions Set Solver Parameters Get the results
Areas
Meshes
Boundary Conditions
• All Boundary Conditions were applied to lines • Velocity applied to surface of the car • Velocity of 35 m/s, 70 m/s and 100 m/s applied in x-direction to “inlet” and lower free stream surface • Relative Pressure of 0 Pa applied to “outlet”
Parameters
• Steady-state with turbulent solver • Fluid properties set to air in standard SI • Solver set to perform more than 500 iterations
RESULTS
Velocity Magnitude 35 m/s
StarCD: Velocity by 35 m/s
ANSYS: Velocity by 35 m/s
Velocity Magnitude 70 m/s
StarCD: Velocity by 70 m/s
ANSYS: Velocity by 70 m/s
Velocity Magnitude 100 m/s
StarCD: Velocity by 100 m/s
ANSYS: Velocity by 100 m/s
Static Pressure 35 m/s
StarCD: Pressure by 35 m/s
ANSYS: Pressure by 35 m/s
Static Pressure 70 m/s
StarCD: Pressure by 70 m/s
ANSYS: Pressure by 70 m/s
Static Pressure 100 m/s
StarCD: Pressure by 100 m/s ANSYS: Pressure by 100 m/s
Conclusion
• Both programs are good to solve these problems • For easy geometries ANSYS/FLOTRAN should be used to get fast results • For complex geometries StarCD gives more reasonable results, but it takes more time to define the boundary conditions
THE END!