Research On The Identification And Control Of Vehicle Noise Source Based On Partial Coherence Analysis

In recent years, the NVH performance of the car becomes more and more important for people to drive light truck commercial vehicle. There are some important issues in the current automotive development to improve the vehicle NVH performance, such as how to find out the car noise vibration problem quickly and accurately, and to solve it effectively.In this paper, according to the evaluation standard of automotive noise and vibration, the corresponding vehicle road test was carried out by comparing the noise and vibration data of benchmark vehicle and test vehicle in different conditions, to verify the test vehicle performance and vehicle structure design, finally some main problems of the test vehicle were discovered. As the noise level of test vehicle is very high, more research was studied in the drum anechoic room to evaluate the vehicle sealing performance, and to analyze the effects of gear and engine speed on noise source in WOT conditions, and to collect the noise and vibration data of the vehicle in uniform motion.The theoretical derivation of partial coherence function was shown in this paper, and compared with coherence function and contrast coherence function. It indicated that the partial coherence function is more effective and more accurate. Combined the multiple input/single output noise source system model and the noise vibration spectrum of the vehicle, the main noise sources were identified and sorted based on partial coherence function.According to the vehicle test and partial coherence analysis results, peak frequency noise of the main noise source, such as car dashboard, car roof radiation noise, air intake system, the rear muffler and tire-pavement noise, were studied. This research has great theoretical value and practical significance, and it provides a new efficient and accurate method to control interior noise.