Race Car Aerodynamics MER033 Lab 6

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Race Car AerodynamicsMER033- Lab 6
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• Purpose
• Characterize the aerodynamic performance of radio
  controlled vehicles
• Methods
• Surface Pressure Distribution Measurement
• Lift/Drag Force Measurements
• PIV (Particle Image Velocimetry)

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The Impact of Aerodynamics on Vehicle Shape

• Compare two race cars
• Both were designed for the Indy 500

• Why are they so different?
• Streamlining
• Aerodynamic Down Force

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The Three Components of Aerodynamic Force
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Lift - Dr. Jekyll

• Down force (Negative Lift)

• Down force increases a tires capability to
  produce cornering force
• Down force stabilizes vehicles at high speed
• Improves braking performance

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Drag - Mr. Hyde

• Reduces top speed
• Helps chasing cars to draft and catch up
• Reduces effective power of engine

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Aerodynamic Down Force and Vehicle Performance
Source Race Car Aerodynamics, J. Katz, 1995
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Radio Controlled Racing

• Perfect size for the Union wind tunnel
• Can outfit with many body styles
• Fast enough that aerodynamics affect handling

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The Vehicles
(a) Ford Taurus NASCAR racer (c)
baja Beetle
(b) 1969 Dodge Charger (General Lee) (d) a
Mini Cooper
(e) Nissan P-35 LeMans Style
prototype racer
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The Instrumentation

• Two models required for each body type
• PIV, Lift/Drag Test Model
• Surface Pressure Model

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Tools

• Wind Tunnel

Force Balance
Particle Image Velocimetry
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The Experiments

• Week 1 Surface Pressure Measurements
• Week 2 Lift and Drag Measurements
• Week 3 Particle Image Velocimetry Tests
• Week 4 Oral Presentations and Web Pages

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Questions?

• References
• Katz, J., Race Car Aerodynamics, Robert Bentley
  Publishing, 1995
• Jeremy Losaw, ME Class of 2002

Funded by the National Science Foundation
(CCLI-9950521)