High-temperature effect on the sound absorption of cylindrically perforated porous materials

A theoretical model and a finite element (FE) model are proposed to evaluate the effect of high temperature on the sound absorption performance of cylindrically perforated porous materials. The theoretical model is established by applying the double porosity theory, in which the perforated porous material is considered as a combination of the porous material matrix and the cylindrical perforation. The FE model is constructed using the pressure acoustics module of the COMSOL Multiphysics software to verify the theoretical model. In these two models, the temperature effect is accounted for by applying the temperature-dependent physical parameters of the air in the porous material. Several representative examples show that the results obtained by the theoretical model agree well with those obtained by the FE model, and the sound absorption peak moves to higher frequencies as the temperature rises. The analysis of the propagation and dissipation of sound energy at different temperatures shows that the increase in temperature can prevent sound from entering the porous medium, thereby delaying the appearance of the absorption peak along the frequency axis. The perforated porous materials exhibit higher sound absorption performance than traditional homogeneous porous materials and, therefore, have enhanced high-temperature sound absorption potential.