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An experiment has been conducted to evaluate the use of force actuators on an aircraft fuselage model interior trim panel as the control element for active control of interior noise. These experiments were conducted on a composite model of a commuter class aircraft. A trim panel was designed specifically for this evaluation, constructed in three large sections and hard mounted to the ring frames of the primary structure. Piezoceramic actuators were bonded to the outer surface of the trim panels. Studies of the interior pressure response due to both the primary source alone and control source(s) alone were conducted as well as the control cases. Initial results provided global reductions of 5 dB for the case where the response was dominated by an acoustic resonance. In all other cases, only local reductions at the error microphones were attained.

The effect of different types of control force actuator models and geometries on the intensity flow between a cylindrical shell and the contained acoustic space has been analytically investigated. The primary source was an external monopole located adjacent to the exterior surface of the cylinder midpoint. Actuator models of normal point forces and in-plane piezoelectric patches were assumed attached to the wall of a simply-supported, elastic cylinder closed with rigid end caps. Control inputs to the actuators were determined such that the integrated square of the pressure over the interior of the vibrating cylinder was a minimum. Test cases involving a resonant acoustic response and a resonant structural response were investigated. Significant interior noise reductions were achieved for all actuator configurations. Intensity distributions for the test cases show the circuitous path of structural acoustic power flow.