Dynamic Analysis of Dissipated Energy for Automotive Sound-proof Structures Including Elastic body, Viscoelastic body and Porous body using FEM in Sound Bridge Phenomena

Abstract

A numerical method is proposed to calculate dynamic dissipated energy for mixed structures including elastic body, viscoelastic body and porous body. A expression to calculate share of dissipated energy for an each element in mixed structures is derived. Using this expression, vibration transmition properties are analyzed for mixed structures composed of porous media sandwiched between steel beam and plastic sheet. Further, a spacer is installed between the steel beam and the plastic sheet in the structures, to analyze deterioration of vibration by the sound bridge phenomena.