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This paper reviews an integrated testing approach for investigating the effects of fluid dynamics phenomena on racecar performance. The approach is based upon a combination of advanced optical diagnostic techniques with computational fluid dynamics (CFD) models to provide a comprehensive understanding of the aerodynamic response of the car. Advanced optical diagnostic techniques available include pressure sensitive paint (PSP, surface flow visualization, aerodynamic loads), temperature sensitive paint (TSP, temperature map and heat transfer), particle image velocimetry (PIV, air velocity and streamlines), and stereovideogrammetry (model movement under loading). The current state of development of these techniques allows a complete integrated systems approach to testing including: hardware, acquisition-analysis software, and a comprehensive comparison with CFD predictions. All of these techniques have a unique hardware platform (Figure 1).

This paper explores the apparent dichotomy between the performance benefits of supercharging and fuel economy. Following an investigation of the tools available for fuel savings, especially drivetrain and engine alternatives, the desirable characteristics and optimum configuration of a supercharger are examined. Engine dynamometer data for a 1.7-liter gasoline engine equipped with a Bendix Supercharger and performance and test data from Bendix-supercharged test vehicles confirm that supercharging provides a means to achieve fuel economy, performance, driveability, and acceptable emissions.

Traction on winter surfaces was measured using three test vehicles, each designed to measure traction for a different purpose: vehicle mobility research (CRREL instrumented vehicle), commercial tire testing (Uniroyal-Goodrich traction tester) and airport runway safety (SAAB friction tester). The traction measured with each method is comparable, but there are systematic differences due to the effects of the surface materials and test and analysis techniques. This comparison serves as the basis for collaboration between the various traction and data analyses for traction testing and evaluation.