Evaluation of Methods for Developing Active Vibration Control in Aircraft Trim Panels

One of the contributions to noise level inside aircraft cabin is due to the vibration of trim panels. Trim panels are mounted on the fuselage, and thus are subject to the vibration caused by aerodynamic boundary layer, engines, propellers and, in the case of rotorcraft, rotor dynamics and aerodynamic noise. Addressing each single vibration and noise source with passive systems is complicated and furthermore limited by the weight restriction every system has to face on an aircraft. On the other hand, the introduction of active mounts can increase the noise abatement capability of the trim panels and can lead to significant reduction of SPL inside the cabin while minimizing modification on structural design of fuselage and saving weight.

Currently trim panels are isolated by mean of rubber mountings, which, as all passive system, have efficiency limitations and are unable of adapting to different disturbances. In the present paper the design and the numerical simulation results of a system based on active mounts is presented. The proposed system use an accelerometers to detect vibration on specific sections of the fuselage, and process this signal to drive the active mounts actuators in order to minimize noise radiated inside the cabin.