723 Sound Insulation Control of a Multiple-wall Structure

Abstract

This paper is concerned with sound insulating control by vibration insulation of a multiple-wall structure. A multiple-wall structure is composed of more than two uniformed panels separated by enclosed air gaps. The research model is supposed the multiple-wall structure is subjected to and got through by the acoustic sound. The objective of this research is to improve the sound insulation effect of this structure in a viewpoint of active control. For the improvement, the coupling terms between a plate subjected disturbance force and plates situated next to it are suppressed by feedback control force given from the reciprocal vibration. In consequence, the vibration insulation is accomplished and the vibration is localized in a target component. In this paper, first, the mechanisms of the multiple-wall structure vibration are revealed by modal coupling theory, and from it the coupling terms are check out. Next, the vibration insulation control by suppressing the terms is offered to. In the final, the performance of this novel sound control theory is demonstrated by the numerical analyses.