Effects of non-linear damping on random response of beams to acoustic loading

Abstract

Effects of both non-linear damping and large deflection are included in a theoretical analysis in an attempt to explain experimental phenomena observed for aircraft panels excited at high sound pressure levels: that is, the broadening of the strain response peak and the increasing of the modal frequency. Two non-linear damping models are considered in the analysis, with a single-mode approach. The root-mean-square (RMS) maximum deflection, the RMS maximum strain, the spectral density function of maximum strain and the equivalent linear frequency for simply supported and clamped beams are obtained. It is demonstrated that non-linear damping contributes significantly to the broadening of the strain response peak and to the RMS maximum deflection and strain, and frequency.