Decomposition and visualization of vehicle noise sources with transfer path acoustical holography

Decomposition of noise sources is an essential step to reduce the vehicle pass-by noise. Dynamic transfer path analysis has been used to describe the relation between the noise sources of the vehicle and the response point in the pass-by test. A transfer path acoustical holography method is introduced to decompose and visualize the vehicle pass-by noise sources, and the method is illustrated with a simulation of four moving point sources. The decomposition results for the four sources using transfer path acoustical holography are compared with that using acoustical holography method. It shows that the transfer path acoustical holography method has a better decomposition result. Finally, the proposed method is used to decompose the contributions of the sources in a commercial truck. The results show that the transfer path acoustical holography can be used to decompose and visualize the vehicle's noise sources in the pass-by test.