CONTROL OF AIRCRAFT INTERIOR NOISE USING GLOBALLY DETUNED VIBRATION ABSORBERS

A simplified analytical structural acoustics model of a propeller airc raft is developed to study the potential of mechanical vibration absor bers for reducing interior noise. The results show that globally detun ing the absorbers to minimize an interior acoustic cost function gives attenuations of the order of 6-10 dB of the blade passage frequency i nterior noise when properly configured. The analysis also predicts tha t globally detuned absorbers consistently outperform tuned absorbers i n which the base motion is directly minimized. (C) 1997 Academic Press Limited.