Title: Prediction of the effect of porous sound-absorbing material inside a coupled plate cavity system

Authors: Zhengqing Liu; Mohammad Fard; John Laurence Davy

Addresses: Noise and Vibration Group, School of Engineering (SENG), RMIT University, Melbourne 3001, Victoria, Australia ' Noise and Vibration Group, School of Engineering (SENG), RMIT University, Melbourne 3001, Victoria, Australia ' Noise and Vibration Group, School of Engineering (SENG), RMIT University, Melbourne 3001, Victoria, Australia

Abstract: This paper predicts the acoustic properties of the porous sound-absorbing material in a box cavity by conducting a finite element method (FEM) analysis, and it verifies the estimated acoustic properties using an appropriate experimental method. The cavity is a rectangular box with five rigid walls and one flexible wall which is an aluminium plate. The porous sound-absorbing material is attached to the inner surface of the plate, in order to modify the coupling between the plate inner surface and the air inside the box. The plate is mechanically excited by using an electromagnetic shaker, which is imitating structure-borne noise. The generated noise is recorded by using pressure microphones at the different locations inside the box. The results show that there is good agreement between the FEM prediction and the measurement for the acoustic response at different locations inside the rectangular box. Sound pressure peaks due to cavity modes are effectively reduced by adding porous sound-absorbing material. Furthermore, sound level in the cavity is reduced by a similar amount in both the numerical simulation and the measurement, when a porous sound-absorbing material is added. The developed FEM model is used to characterise the effects of porous sound-absorbing material in reducing the structure-borne radiated noise.

Keywords: porous materials; sound-absorbing materials; coupled plate cavity systems; finite element method; FEM; acoustic response; sound absorption; noise absorption.

DOI: 10.1504/IJVNV.2016.081825

International Journal of Vehicle Noise and Vibration, 2016 Vol.12 No.4, pp.314 - 330

Available online: 25 Jan 2017 *

Full-text access for editors Access for subscribers Purchase this article Comment on this article