Abstract
Reducing the aerodynamics noise is one of the major technical issues on the development of practical industrial products. Particularly, automotive engineers have to solve many problems of aerodynamic noise. In evaluation for those aerodynamic noise, both sound and flow field characteristics are fundamental information. However, these sound and flow fields are usually measured and evaluated independently. In the present work, a simultaneous measuring technique for sound and flow fields is introduced. The technique is combination of the Spatial Transformation of Sound Fields (STSF) System and the PIV system. Combining those measuring systems, the relation between turbulence structure and origin of noise will be clarified with measuring both sound and flow field simultaneously. The results of the test measurement show that the present measurement method should be a useful tool for analyzing and evaluating the mechanism of generation of aerodynamic noise in the flow.