Direct Numerical Prediction of Aerodynamic Noise Emitted from a Generic Automobile Rear-View Mirror

摘要

We numerically simulated the aerodynamic noise generated from the unsteady flow around a generic model of automobile rear-view mirrors in this study. This generic model is made by cutting a hemispherical cylinder into half lengthwise, and placed on a flat plate. The governing equations employed in the present numerical simulation are the compressible Navier-Stokes equations, where no additional models of sound generation and propagation are used. Results show that acoustic pressure waves are generated from the disturbed wake of the mirror model and propagate into the far field. In addition, the spatial distribution of the sound pressure level (SPL) in the far field has a similar tendency to that of the experimental data. These results show that useful data on aerodynamic noise can be obtained by the simple computational method presented in this study, and utilized to make a preliminary design to reduce the aerodynamic noise.