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At high cruising speed, the car A-pillars generate turbulent air flow around the vehicle. The resulting aerodynamic pressure applied on the windows significantly contributes to the total cabin noise. In order to predict this particular noise contribution, the physic of both the flow and the cabin needs to be accurately modeled. This paper presents an efficient methodology to predict the turbulent noise transmission through the car windows. The method relies on a two-step approach: the first step is the computation of the exterior aero-dynamic field using an unsteady CFD solver (PowerFLOW); the second step consists in the computation of the acoustic propagation inside the cabin using a finite element vibro-acoustic solver (ACTRAN). The simplified car cabin of Hyundai Motor Company, studied in this paper, involves aluminum skin, windows, sealant, inner air cavity and acoustic treatment inside the passenger compartment (porous material, damping layer).

To assess the acoustic performance of modern automotive air filters, both the air-borne engine noise propagating through the interior air of the system (known as “pipe noise”) and the structure-borne noise radiated by the shell (“shell noise”) should be evaluated. In this paper, these different propagation paths are modeled using the finite element solver Actran on industrial test cases set-up by SOGEFI Air and Cooling Systems. The test-case is designed in such a way that the different propagation paths are assessed separately. First the engine acoustic pulsation that is transmitted through the filter's structure is considered. Second, the noise radiated by the shell excited by mechanical forces at the support location of the filter is evaluated. Finally, the acoustic transmission loss of the filter is predicted. The ingredients of the finite/infinite element models are reviewed in details in the paper.