Abstract: The accuracy of overall flow simulation on original design is determined according to the comparison between calculation and wind-tunnel test results of the aerodynamic performance parameters of vehicle model under two different states (with air inlet grill opened or closed), while the accuracy of aerodynamic noise simulation with a grid size of 2mm is obtained based on the comparison between the calculation result of the sound pressure level of tested points on side window surface using DES method and test results. The flow visualization of new scheme and original design using Q-criterion shows that the flow state of wake flow region of new rear-view mirror is improved. The comparison of the turbulent pressure fluctuation on side window surface shows that the influence of shape change of rear-view mirror is trivial, while the sound pressure fluctuation obtained by Lighthill acoustic analogy method has a significant difference, the sound pressure fluctuation of new scheme in the range of 2000~8000Hz is obviously reduced. The sound source distribution and improvement effects of Beamforming test are consistent with CFD calculation predictions and have a very good correlation with the interior sound pressure level test. The above studies show that Q-criteria flow visualization can be applied to the quantitative evaluation of aerodynamic noise, and the sound pressure fluctuation is the most important evaluation measure for the aerodynamic noise simulation of rear-view mirror and should not be ignored.

Key words: rear-view mirror, aerodynamic noise, wind tunnel test, beamforming, rear-view mirror, aerodynamic noise, turbulent pressure fluctuation, sound pressure fluctuation, wind tunnel test