Laminated Composite Acoustic Performance

By combining the theory of acoustic and vibration, material science and using finite element method(FEM), the design principle for laminated composites was studied in this paper, and then it is presented that the noise reduction can be predicted by finite element method in that it is proved that the FEM results is well coincident with the experimental ones. As an important component in laminated composites, the foamed polymer material (polyurethane foam, PUF) is also studied in this paper. The viscoelastic property's influence on absorption property is studied by FEM, and the relationship between the macroscopical physical properties and the absorption property is researched by experiment. At last, according to the requirement of noise reduction in a certain frequency scope, we optimized the thickness of each layer in the laminated composites by FEM and optimization theory to realize effective using of material.The study proved that FEM is an effective and accurate method for the laminated composites' research and designation in middle and low frequency scope.