Investigation of the sound absorption of piezoelectric composite absorber submerged in water

In this paper , we investigated the sound absorption of underwater piezoelectric composite absorber, which are composed of an piezoelectric layer and several rubber layers. Using the transfer matrix of sound pressure and particle velocity of piezoelectric layer and rubber layer and the continuity condition at the interface between two layers, the total transfer matrix of the piezoelectric composite absorber was calculated by using recursive method. Then, the sound absorption coefficient and the control voltage of the composite absorbers were deduced. By numerical calculation, we analyze the variation of the sound absorption coefficient and the control voltage of the composite absorbers when the boundary conditions of the absorbers and the parameters of rubber layer are changed.