Contribution Analysis Of Vehicle Pass-by Noise Based On Transfer Path Analysis

Transfer path analysis method has been widely applied in many fields of sound and vibration control engineering because of its advantages of simple measuring,fast calculation and so on.At present,the application of transfer path analysis method in the automotive field is mostly seen in interior noise contribution analysis,but its research on the contribution analysis of pass-by noise is rarely reported.This paper conducts a comprehensive research and discussion on the application of transfer path analysis in contribution analysis of pass-by noise and applies this method successfully to a pass-by noise test of a passenger car,further,quantifies and sorts the main sources that make a greater contribution to the pass-by noise.First of all,based on the assumption of linear time-invariant system,the theory of transfer path analysis has been proposed in detail,and expounded the basic model of contribution analysis briefly.And then,a brief simulation analysis was carried out.The results show that,the transfer path analysis method can obtain the contribution analysis result accurately.However,at the same time,because of the unavoidable errors in the test process,the frequency response function becomes diseased,and further,when there is a little noise present in the test signal,there will be a large error in the calculation result,which affects the reliability of the result badly.In light of this,to overcome the influence of noise,and obtain more accurate and reliable contribution analysis results,a new adaptive truncated singular value decomposition method was given based on the conventional truncated singular value decomposition in this paper.Moreover,the simulation analysis results show that the calculated results are in good agreement with the theoretical values after regularization.In addition,compared with the conventional truncated singular value decomposition,the results obtained by the adaptive truncated singular value decomposition are more accurate.Furthermore,combined the truncated singular value decomposition,the transfer path analysis method was applied in indoor pass-by noise test.The test results show that the transfer path analysis method quantifies and sorts the main sources that make a greater contribution to the pass-by noise successfully,and is of important guiding significance for further development of effective noise control measures.In the end,to further verify the reliability of the analysis results of the contribution from each source to the pass-by noise,a new verification method by adding an additional sound source was proposed,and deduced its basic theory in detail.Moreover,the test results show that transfer path analysis based contribution analysis method for pass-by noise can get an accurate and reliable result,suitable for engineering test.