Ji Z.

The perforated tube elements are widely used in silencers to regulate the flow in order to reduce the back pressure and to increase the noise attenuation. Studies on the silencers demonstrated that a multidimensional approach is required for the accurate prediction of acoustic attenuation performance at higher frequencies, while the simple one-dimensional theory is sufficient at lower frequencies. The one-dimensional analytical approaches and the three-dimensional numerical methods have been applied to predict the acoustic attenuation performance of the straight through perforated tube silencers. However, the works have chosen not to elaborate on the effects of mean flow and geometry with respect to the acoustic attenuation of this configuration. The objective of present work is (1) to extend the substructure boundary element method (BEM) to predict the acoustic attenuation performance of the straight through perforated tube silencers with mean flow, and (2) to examine the effects of mean flow and geometry on the acoustic attenuation performance of the straight through perforated tube silencers.