Abstract: A method and system are provided for reducing flow-induced resonance in a cavity of a structure. At least one pair of diaphragms are mounted in a housing and separated from one another such that a chamber is formed therebetween within the housing. A first diaphragm of the pair of diaphragms is oscillated in accordance with a time-varying function. A second diaphragm of the pair of diaphragms is oscillated inversely to the first diaphragm so that pressure in the chamber formed therebetween changes in correspondence with the time-varying function. The chamber is vented at a position flush with the surface of the structure along the leading edge of the cavity. As a result of such venting, the pressure in the chamber that changes in correspondence with the time-varying function introduces a corresponding time-varying disturbance into the shear layer along the leading edge of the cavity.

Abstract: A method and system are provided for reducing flow-induced resonance in a structure's cavity. A time-varying disturbance is introduced into the flow along a leading edge of the cavity. The time-varying disturbance can be periodic and can have the same or different frequency of the natural resonant frequency of the cavity. In one embodiment of the system, flaps are mounted flush with the surface of the structure along the cavity's leading edge. A piezoelectric actuator is coupled to each flap and causes a portion of each flap to oscillate into and out of the flow in accordance with the time-varying function. Resonance reduction can be achieved with both open-loop and closed-loop configurations of the system.