Analysis of Transmission Loss for Pneumatic Valve-used Mufflers Based on Plane Wave Multi-sound-Sources

Traditionally, the transmission loss of valve-used mufflers is calculated by means of the four-parameters based on the single plane wave sound source, which can not reflect the de-noise performance of muffler in case of distribution sound sources. The method for computing transmission loss by resolving muffler based on the plane wave multi-sound-sources is proposed. And then the simulation is performed in MATLAB environment. The calculation results show that the proposed method, as is opposite to the method for computing transmission loss using the single sound source, can represent the de-noise effect of muffler on the distribution sound sources and approximate the reducing noise performance of the actual muffler. The maximum relative error between the analytical result in the proposed method and those in the single sound source method and the calculation in lecture [6] is 20%.