Abstract. This thesis investigates the in uence of uid loading on the motion of vibrat- ing structures and on the radiated sound power. For vibrating plates models incorporating structural-acoustic coupling have been implemented.For plates as well as for arbitrary geometries, formulations for the acoustic pressure and the radiated sound power are presented. To correlate simulation results for the structure with an experimental setup, a Rayleigh Ritz model for layered plates incorporating piezoelectric actuators and sensors is used. The acoustic  eld equations are derived, near- and far-  eld equations for the acoustic perturbation pressure are presented. The overall radiated sound power is then estimated using quantities local to the vibrating surface only.