EXPERIMENTAL STUDY OF SMART SEGMENTED TRIM PANELS FOR AIRCRAFT INTERIOR NOISE CONTROL

A smart trim panel used as a secondary source for active noise control in aircraft is developed and tested. The smart trim panel is a rectangular segment of aircraft trim panel which is suspended by a flexible support. This support converts the stiff trim panel into flexibly mounted pistons which can be driven by light-weight and low-profile force actuators. The smart trim panel has many advantages as an acoustic source over traditional loudspeakers: it is of lower profile, lower mass, and requires only a simple modification of materials already installed on aircraft. The static and dynamic properties of a smart trim panel are studied, verifying that when subjected to low-frequency (<500 Hz) excitation, it vibrates in the efficiently radiating piston mode. Real-time active noise control experiments are conducted in a laboratory-scale fuselage model using the smart trim panels as secondary sources. Global attenuation of sound pressure levels of up to 15 dB is realized.