Abstract：The pressure response functions and the corresponding four-pole parameters of two-dimensional rectangular and cylindrical mufflers have been obtained by modal expansion methods. Thus, transmission loss (TL) calculation model of different shape mufflers has been derived. In order to verify the present calculation model, the TL results of a two-dimensional cylindrical muffler obtained by the proposed model has been verified by comparing with that obtained by the three-dimensional finite element method. It is demonstrated that the proposed model is more computationally efficient than the finite element method with adequate computational accuracy. This model is more accurate if the area of the surface source is comparatively large, compared with the TL results by Green’s function method.
2011, Vol. 30 
