Transmission loss prediction for silencers by using the combination of boundary element method and numerical collocation approach

A technique combining the boundary element method (BEM) and numerical collocation approach was proposed to calculate the transmission loss of silencers with arbitrary cross-section. The silencer was divided into several substructures. The BEM and the numerical collocation approach were employed combinedly to evaluate the impedance matrices of substructures with non-regular cross-section and axially uniform cross-section respectively, and then the impedance matrices for all substructures were achieved. The transmission loss predictions of several silencers agree well with the results by BEM. The computational efficiency was analyzed and compared with that of the traditional substructure method, the combined technique may save computational time efficiently.