A computational model for the sound absorption coefficients of multi-layer non-wovens

Abstract

Using the theory of Zwikker and Kosten for sound propagation through a porous flexible media and the sound propagation boundary conditions at adjacent interfaces, a general computational model for the sound absorption coefficients of multi-layer non-wovens, αn, is presented in this paper. The iterative algorithm for calculating αn is given using the back-stepping method. In order to yield the highest sound absorption coefficients in the audible frequency range the model has been used for numerical calculation of the intrinsic characteristics of non-woven materials. The simulation demonstrates that the multi-layer structure of non-wovens can have good sound absorption over a prescribed frequency range by choosing the appropriate parameters for each layer. This model can also be used to calculate the absorption coefficients of a multi-layer non-woven comprising different non-woven components, and this can then provide a theoretical support for product design.