LOW-FREQUENCY SOUND-TRANSMISSION THROUGH CLOSE-FITTING FINITE SANDWICH PANELS

The experiment presented in this paper is to investigate and analyze t he noise reduction at low frequency by lining the cavity between two p anels of a finite double panel structure with porous material. The str uctural-acoustic coupled system of a sandwich structure backed by a re ctangular acoustic cavity of rigid walls is discussed. It is found tha t the sound insulation of sandwich panels with air cavities containing and porous material is more effective than that of the single-layered panel at low frequency. (C) 1998 Elsevier Science Ltd. All rights res erved.