Active Control of Sound Radiation Pressure

This paper is concerned with the problem of suppressing the acoustic radiation pressure generated by a structure vibrating in air. The approach is to control the vibration of the modes of the structure most responsible for the radiation pressure. This control is carried out by active means, i. e., by feedback control. As a numerical example, the problem of active control of the far-field radiation pressure generated by the vibration of a simply-supported rectangular elastic plate is considered. The influence on the control effectiveness of various design parameters, such as the number of controlled modes, the choice of controlled modes, the number of actuators and the location of the actuators, is investigated. The conclusion is that, depending on the magnitude of the excitation frequency, satisfactory control can be achieved by using a sufficient number of actuators and by controlling a relatively large number of modes.