Vibroacoustic performance of composite honeycomb structures

This paper is concerned with the prediction of vibroacoustic performance of the honeycomb sandwich panels in a close-fitting enclosure. The acoustical transfer function of this panel in the close-fitting enclosure are presented. The noise reduction performance of the honeycomb sandwich panels is investigated through a set of experiments verifying the potential and usefulness of the honeycomb panel in practice. The results have confirmed that the absorption at the mass-spring-mass resonance in the case of a honeycomb panel (comparatively stiff) with a thin plate is more efficient with minimum weight. Adding absorption minimizes the effect of the 'mass-air-mass' resonance that usually impairs the low-frequency transmission loss, and offers good performance at higher frequencies. The potential of composite honeycomb sandwich panels for reducing low frequency noise (<500 Hz) is demonstrated. (C) 2006 Institute of Noise Control Engineering.