Noise Mitigation Using Passive Vibroacoustic Attenuation Devices

摘要

A Passive Vibroacoustic Attenuation Device (PVAD) is an integrated structural vibrationmitigation device and acoustic damper. The PVAD was developed to provide low frequencynoise reduction where acoustic blankets display limited effectiveness. This work presentsmodeling of the PVAD and composite cylinder test bed, simulations, experimental results usingprototype PVADs on a 2.75-meter composite cylinder. The measured experimental datasupported conclusions from the model simulations and predictions. Narrow-band reductions of10 dB were demonstrated at low frequency acoustic resonances. More than 4 dB RMS acousticreduction was measured over the frequency range below 160 Hz where the treatment wasdesigned to target.