Active control of noise radiation from vibrating plate excited by a harmonic line moment is analytically investigated. This study model of simple supported rectangular plate with a line moment excitation is used to simulate the vibration of ship hull or fuselage from the flutter of ship deck or aircraft wing respectively. The control is achieved by various configurations of piezoelectric actuators. The strategy of radiated power minimization is used to obtain the optimal control input unit voltage. The numerical results show that the significant attenuation of noise radiated power for volumetric modes in the low frequency range can be achieved with one control actuator located at the center of plate, irrespective of whether the excitation is on or off resonance. The efficiency of the active control is dependent on the location of the line moment and the actuators. It is also shown that the modal suppression and modal restructuring are two physical mechanisms of radiated power attenuation.
