Assessment of Structure-borne Road Noise for Battery Electric Vehicle: Prediction and Improvement

In the absence of engine noise, road-induced noise has become a major concern specifically for Battery Electric Vehicles (BEVs), impacting Sound Pressure Level (SPL) for both drivers and passengers. Under the influence of random road load inputs, structural vibrations which transfer from road and tire to suspension to vehicle body, the cabin interior noise, particularly at lower frequencies, is significantly affected. To improve the road-induced low-frequency structure-borne noise behaviour, which frequently perceptible as ‘booming noises’, a study was carried out to assess predominant noise sources present in vehicle and to suggest refinements in reducing noise levels. By considering random excitations of road profile through tyre patch using CD-Tire model, vehicle interior noise was computed. Subsequently, to get insight of dynamic behaviour of vehicle, various diagnostic assessments to understand the influence from structure and paths were deployed. Major contributors from body structure panels were identified and thereafter structural enablers were employed to attenuate the booming phenomenon. The approach shown here has the potential to identify and optimize BEV noise in a more comprehensive and effective way.