Correlated Beamforming Method for Relevant Aeroacoustic Sources Identification

Beamforming technique is widely used in automotive industry to identifiy aeroacoustic sources generated by interaction of the flow with the car body. Despite its great interest, an important defect of this approach is that it gives a map of aeroacoustic sources around the vehicle from an exterior point of view, typically several meters from the side of the car. Therefore, it does not identify only the sources really heard inside the vehicle but all exterior dominant sources such as wheel house noise which can have a negligible impact on the interior noise. In this study, a beamforming treatment (called MALIS) that calculates maps from an interior point of view is presented. The basic idea is to correlate external beamforming results with signals from microphones inside the vehicle in order to estimate the energetic contribution of aeroacoustic sources to interior noise.