汽车后视镜与雨刮的风噪优化

An Optimization of Vehicle Rear-view Mirror and Wiper Wind Noise

为得到某SUV的车内噪声,分别采用计算流体力学法和统计能量法对该车型进行外部流场和乘坐舱内噪声计算,获得驾驶员头部区域的声压级曲线。在原车仿真结果基础上,对后视镜和雨刮进行改进,并采用数值仿真和道路试验对原车和改进后的噪声进行评估和对比。仿真和试验得到的声压级曲线整体趋势一致,表明仿真结果的有效性;后视镜和雨刮改进后,仿真结果显示两种改进方案的噪声,在全频段均有改善,其中声压级最大降幅达5. 6dB(A),两种方案的总声压级分别降低1. 5和1. 8dB(A);路试结果显示在干扰噪声较小的高频段,改进后的声压级有较明显的降低,部分高频段最大降幅达5. 1dB(A),两种方案的总声压级分别降低0. 2和0. 7dB(A),表明了改进的有效性和研究方法的可行性。

The external flow field and the interior noise of the passenger compartment of a SUV are calculated by computational fluid dynamics and statistical energy method respectively,and the sound pressure level( SPL)curve at driver’s head region is obtained. Based on the simulation results of original vehicle model,rear view mirror and wiper are modified,and the noise evaluation and comparison between before and after modifications are carried out by numerical simulation and road test. The SPL curves obtained by simulation and road test have the same overall tendency,showing the effectiveness of simulation results. The results of simulation indicate that both rear-view mirror and wiper modification schemes have noise reduction effects in full frequency range,in which the maximum reduction amplitude in SPL reaches 5. 6dB( A) and the total SPL with both schemes reduce by 1. 5 and 1. 8dB( A)respectively. The results of road test show that in high frequency segment with relatively low noise,the SPL after modification has apparent fall,with the maximum reduction amplitude reaching 5. 1dB( A) in some high-frequency band. And the total SPL with both modification schemes reduce by 0. 2 and 0. 7dB( A) respectively,demonstrating the effectiveness of modifications and the feasibility of study method.