The Objective Method of Evaluating Aspiration Wind Noise

The automobile industry places a major emphasis on reducing car interior noise levels to attain a more pleasant and comfortable ride. In recent years, improved superhighways, allowing higher car speeds, have created a rise in the aspiration wind noise due to high aerodynamic pressure differentials causing air to pass by the body seals. No longer is a car body sealed merely against water leaks. With the increased use of air conditioning in cars, the closed side windows have lowered the ambient interior noise, thereby exposing the broad band frequency aspiration wind noise. A need for an objective method for the quality control and development of body seals was imminent. This report analyzes the aspiration wind noise parameters and presents two objective methods of measuring aspiration wind noise. These methods, using a meter, replace the previously used method of subjective evaluation of the loudness of wind noise.