偏相干分析在客车降噪中的应用  

Application of Partial Coherence Analysis in Interior Noise Reduction of Passenger Cars

作　　者：王茜影 谢小平[1,2] 李阳[1] 杨悦 王晨辉[1] WANG Xi-ying;XIE Xiao-ping;LI Yang;YANG Yue;WANG Chen-hui(The State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body,Hunan University, Changsha 410082, China;CZ-HNU Institute of Machinery Equipment, Changzhou 213000, Jiangsu China;Xian Silver Bus Co. Ltd., Xi’an 710089,)

机构地区：[1]湖南大学汽车车身先进设计制造国家重点实验室,长沙410082 [2]常州湖南大学机械装备研究院,江苏常州213000 [3]西安西沃客车有限公司,西安710089

出　　处：《噪声与振动控制》2017年第3期112-116,共5页Noise and Vibration Control

基　　金：国家自然科学基金重点项目资助(11232004);中国新能源汽车产品检测工况研究和开发项目-长沙资助项目

摘　　要：车内低频噪声一直是汽车NVH研究关注的重点问题,常需要找到对噪声影响较大的振动结构进行改进,但是振动对场点的贡献并不能代表对整个声场噪声的贡献量。针对多峰值多场点的车内声场问题,引入"总相干系数"和"相干系数和"的概念对现有的偏相干分析方法进行改进。对某型客车的车内噪声进行小波包分解,得到车内声场的声学特性,确定研究的频率范围。通过对各板件振动与车内测点噪声信号进行偏相干分析,确定对车内声场影响较大的结构,并在实车上实施了改进措施。结果表明,车内噪声测点声压级降低0.5 d B^2 d B,为有效降低客车车内噪声提供了指导方向。Interior low-frequency noise has been the focus of automotive NVH research.It is necessary to detect and improve the vibrating structures that have great impact on the interior noise.However,contribution of vibration to the noise of field points is unlikely to completely represent the contribution to the whole interior acoustic field.For the interior acoustic field with multiple frequency peaks and multiple field points,the“total coherence coefficient”and“coherence coefficient sum”are introduced as two new parameters to improve the existing partial coherence analysis method.Then,the interior noise of a passenger car is analyzed by wavelet packet decomposition.The acoustic characteristics of the interior acoustic field and the concerned frequency range are obtained.Through the partial coherence analysis of the vibration of panels and interior noise signals at the measurement points,the structures which have greater impact on the interior noise are identified.And the improvement measures are carried out for the car.The results of the test show that the sound pressure level of the interior noise of the field points is reduced by0.5dB-2dB.This work provides the guidance for reducing the interior noise of passenger cars.

关 键 词：声学 总相干系数 偏相干分析 低频噪声 小波包分解 

分 类 号：TB535[理学—物理]