The Vibration Of Each Wall Panel Of The Car On The Indoor Acoustic Noise Contribution Analysis Research

Noise pollution has a growing trend with the improvement of industrialization, Especially the low frequency noise has significant adverse effects on the human body. For vehicle interior noise, the frequency and the source of the noise is very complex, and the vibration of the wall panels is mutually coupled for the body panels, so it is very important to find a correct and efficient technology of the vibration source identification to find out the most noise contribution of the wall panels on the ear. In the article, we find out a recognition method of the most noise contribution of the wall panels on the ear which plays a key role on reducing the noise and improving the riding comfort. The article used a certain SUV car for test and the method of the test and theory combining the simulation. It obtains the vibration and noise signals of each measuring point through the experiment to ensure the theory has plenty of practice basis. Using the method of the test and theory combining the simulation to analyze the contribution on the vehicle indoor though the vibration of the wall panels. The following is the main research work of this article:First of all, we get the vibration of the engine and the wall panels and the noise of the driver’s ear, though the method of wavelet analysis, it is concluded that the noise of the driver’s ear within 0~250Hz accounting for the large proportion and take advantage of the feature vector signal to obtain the source of the wall panel’s vibration.Secondly, we can find out the largest noise contribution of the wall panels on the ear though the analysis of the vibration of the wall panels and the noise of the driver’s ear by using partial coherence method.Then, using Catia to establish the simplified model of the body of the experimental SUV,using LMS Virtual.Lab Acoustics to analyse the structure of the modal analysis and modal analysis the Car modal structure and room acoustic modes, getting the modal frequency and modal shape In the range of 20 ~ 250 Hz.Using the modal information to analysis the reason why there is much noise in certain frequency of the test.Finally, import the divided grid of the finite element model into the LMS Virtual.Lab, solve the acoustic contribution of the wall panels on the driver’s ear, find out the largest noise contribution of the wall panels. It is concluded that it is able to identify the acoustic contribution of the wall panels by partial coherence method, but it is required the body structure modes and car cavity acoustic modes to optimize and modify the vehicle body structure.