Modeling of sound transmitted, into a cavity through a composite plate using coupled FE/BE method and control of acoustic pressure using piezoelectric actuators

A coupled finite element/boundary element method is developed for the fully coupled structural/acoustic/piezoelectric system. This approach uses the dual reciprocity boundary element method to describe time dependent acoustic field and the finite element to structures and piezoelectric materials. A time-domain formulation of the coupled method is obtained. Based on the coupled time domain formulation, a linear quadratic regulator and a feedforward controller are applied to reduce the acoustic pressure transmitted into a cavity through a composite plate using embedded piezoelectric actuators. The controls of interior acoustic fields due to excitations at different frequencies are investigated, transmission losses and deflection of the plates of the controlled and uncontrolled systems are presented.