Advanced Experimental Techniques and Their Application to Automotive Aerodynamics

Advanced experimental techniques have been developed for application in the Volkswagen automotive wind tunnels. Such procedures are: laser-Doppler anemometry (LDA) for detailed flow-field measurements; laser-light-sheet technique for flow visualization; probe positioning by a robot; and frontal-area determination by a laser-reflection system. Experiences with these advanced experimental techniques are reported in some detail. Examples of test results are shown, and the different application areas as well as the usefulness of the various methods for the advancement of automotive aerodynamics are discussed.