Reactive silencer modeling by transfer matrix method and experimental study

This paper investigates the acoustic performance of a reactive silencer for two special cases using numerical and experimental techniques. The plane wave based models such as the transfer matrix method (TMM) can offer fast initial prototype solutions for silencer designers. In this paper, the principles of TMM for predicting the transmission loss (TL) of a silencer are briefly presented. The method is applied for each silencer configuration and the numerical predictions are compared with the results obtained by means of an experimental set up. Only stationary, non-dissipative silencers are considered. The acoustic performances of the experimental set up are analyzed as compared with the theoretical results of the plane wave method approach. Comparison takes into account the low frequency range where the firing engine frequency and its first order harmonics are the main sources of noise.