Effect on Passenger Car Wind Noise Sources of Different A-Post Configurations

Abstract

Driving comfort of today's middle and upper class passenger cars is an essential competition criterion. One important of such criteria pertains to interior noise. Experimental work revealed the A-post/side- window junction as an area of primary significance. Here flow separations are likely to occur causing severe fluctuating pressures on the side-window with ensuing accoustic radiation into the car interior. Moreover local flow properties are particularly sensitive towards inclined inflow typically occuring under realistic side-wind conditions. Since there is a direct proportionality between exterior surface pressures and interior noise the former may be used to judge the quality of different car-contour configurational changes. Therefore an experimental program was initated to systematically investigate the effects of different configurational parameters on the surface pressure characteristics in the side-window area for different inflow-angles (yaw-angles).