Passenger Car Aerodynamic Noise Optimization Based on Sensitivity Analysis

A computational fluid dynamics model was established to extract the pulsation pressure of the windows by taking the passenger car aerodynamic noise as the research object. The pulsation pressure was applied as excitation to the vehicle acoustic cavity model to simulate the noises at the driver's ears, and the simulation results were in good agreement with the experimental data. The intensity of Curle noise sources on car surface was taken as the optimization objective, and the sensitivity was identified by discrete adjoint method, then the rearview mirror, A-pillar section and hood were selected as the optimization areas. The Hamersley test design method was used to construct the sample space, and the free mesh deformation technique was used to parameterize the sample point model and the corresponding sound power value was calculated. The Kriging interpolation method was used to create the proxy model, and the multi-island genetic algorithm was used for global optimization. The optimization results show that the maximum sound power level of the window surfaces decrease by 2 dB, and the sound pressure level near the driver's ears drops by 0.7 dB(A). © 2022, China Mechanical Engineering Magazine Office. All right reserved.