Simulation analysis of transmission loss in the vibrating end plate of an expansion chamber silencer

The boundary element method (BEM) is frequently employed to predict the transmission loss (TL) of an expansion chamber silencer with a rigid walled boundary, while the effect of the vibration of the end plates of the expansion chamber silencer is usually ignored. However, when the airflow or acoustic pressure in a duct is large and the end plate of the expansion chamber silencer is not thick enough, the effect of the vibration of the end plate should not be ignored. In this paper, based on a coupling of the BEM and the finite element method (FEM), the numerical results illustrate the existence of the effect on the TL of the vibrating end plates. Furthermore, numerical experiments also show that for an expansion chamber of constant size, the thicker the end plate, the less influence the vibration of the end plate has on the TL. And this may be helpful for the design of silencer. Hirzel Verlag EAA.