汽车后视镜气动噪声仿真与实验研究

doi:10.19562/j.chinasae.qcgc.2018.012.015

摘要/Abstract

摘要： 根据计算进气格栅开、闭两种状态的整车模型的空气动力学性能参数对比风洞实验结果,确定了原设计的整体流动仿真的精度;而基于该模型运用DES法计算的侧窗表面测点的声压级与实验结果对比,确定了2mm网格气动噪声仿真的精度。对新方案和原设计运用Q准则的流态显示,表明新方案后视镜尾流区的流动状态得到改善;侧窗表面的湍流压力脉动的对比表明,后视镜外形的改动对湍流压力脉动影响很小;而通过Lighthill声类比法获得的声压脉动却有显著差异,新方案在2 000~8 000Hz范围内的声压脉动明显减小。Beamforming测试的声源分布和改进效果,与CFD计算预测一致,且与车内的声压级测试有很好的相关性。以上研究表明:Q准则的流态显示可用于气动噪声的定性评估;声压脉动是后视镜气动噪声仿真最主要的评价依据,不可忽略。

关键词: 后视镜, 气动噪声, 风洞测试, Beamforming, 后视镜, 气动噪声, 湍流压力脉动, 声压脉动, 风洞测试

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

王俊, 陈如意, 杨健国, 龚旭, 李林. 汽车后视镜气动噪声仿真与实验研究[J]. 汽车工程, 2018, 40(12): 1480-1487.

Wang Jun, Cheng Ruyi, Yang Jianguo, Gong Xu, Li Lin. Simulation and Experimental Study on Aerodynamic Noise of Automotive Rear-view Mirror[J]. , 2018, 40(12): 1480-1487.

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