371 FEM analysis of absorption characteristics of porous materials in Muffler at elevated temperatures

Abstract

This paper deals with analysis for absorption characteristics of porous materials in muffler at elevated temperatures. Elements of absorber are modeled by 3D finite element, which having complex density and complex volume elasticity. By expanding the solution of complex eigenvalue problem with small parameter, equations of motion are derived using first order of asymptotic components. From the equations, contribution of damping elements on modal damping is derived in consideration with multiple modes.