带有环球影像镜头后视镜对汽车气动噪声的影响研究

摘要

To explore the influence of the rearview mirror with the global image lens on the aerodynamic noise,the Lighthill-Curle acoustic analogy method is used to analyze the camera rearview mirrors airflow and the side window of car aerodynamic noise.Vehicles in high-speed driving conditions,the camera mirrors tail gas stream with respect to the original plan changed greatly.By the sound pressure spectrum available,fiequency in the medium-high frequency band,aerodynamic noise of the camera relative to the original proposal SPL (sound pressure level) increased.Finally,the road test results show,the lens program relative the original proposal SPL higherand language clarity decreased,the correctness of the numerical method is verified,and the feasible method of research which controls the rearview mirror aerodynamic noise is proposed.%为探究带环球影像镜头后视镜对汽车气动噪声的影响,运用Lighthill-Curle声类比方法,对带环球影像镜头后视镜尾部气流的流动以及汽车前侧窗处声场进行研究分析.分析表明:车辆在高速行驶条件下,带有镜头方案的后视镜尾部气流相对于原方案发生较大变化,同时通过计算得到声压频谱图可知,频率在中高频段时,带有镜头方案的前侧窗区域的气动噪声相对于原方案的声压级有所增大.最后,为探究带有镜头后视镜对驾驶舱内气动噪声的影响,对带镜头方案和原方案分别进行噪声风洞试验.试验结果表明:带有镜头方案舱内声压级高于原方案,同时测得舱内语言清晰度也有所下降.试验结果与数值分析一致,验证了数值分析的正确性,为汽车后视镜气动噪声地控制提出了理论依据,有利改善司乘人员乘坐的舒适性.