Operational Transfer Path Analysis for the Investigation of Structure-Borne Noise Paths of a Vehicle

Dealing with vehicle interior noise, structure-borne noise is the main disturbance up to 500 Hz. The noise levels are mostly associated with the tyre dynamics and the tyre/road interaction. Specifically, the road irregularity generates tyre vibrations that propagate through vehicle components and generate cabin noise. For tyre manufacturers, a deep knowledge of the transfer paths represents then a crucial step towards the modelling of structure-borne noise. In order to quantify these paths, Operational Transfer Path Analysis is a powerful tool that provides insights into how tyre design affects the noise generated. In this paper, an approach to determine the most critical paths to structure-borne interior noise of a specific vehicle is presented. To this end, a dedicated experimental campaign was set up to characterize a specific vehicle. The vehicle was tested considering various set of tyres and test tracks. The vehicle was instrumented with accelerometers installed on the four wheel hubs, and microphones were positioned inside the cabin. Different representations of the contribution paths are proposed, demonstrating the capability of the approach to analyse the most critical contributors to structure-borne noise.