Improving the acoustic comfort of vehicle structures by padding rubber layer on interfaces

This paper deals with the noise reduction of coupled fluid-structure system in low frequency band. Rubber layer is introduced to junction between substructures and acts as passive control to reduce noise in the cavity and vibration in the system. The modification of the junction (geometry parameters) results in a local modification of the global system stiffness. Thus the noise and the vibration in the system can be modified if appropriate parameters are chosen. A hybrid modal synthesis method is proposed to investigate the forced responses of fluid-structure system, which allows studying the system behavior with few degrees of freedom. An optimization procedure following an interpolation process is provided to reduce noise level in the cavity. The optimal design configuration is then analyzed from a modal overview. The efficiency of this noise reduction strategy is demonstrated by a numerical example.