径向声子晶体隔声特性

Acoustic insulation properties of radial phononic crystals

A cylindrical shell radical phononic crystal model arranged alternately between two homogenous materials is constructed in this paper. First, the theoretical analysis was based on the axial symmetry propagation in the model. The sound pressure transmission coefficient and the sound insulation expression were derived based on the establishment of acoustic wave propagating transfer matrix from the inside out. The sound insulation properties of cylindrical shell of radial phononic crystals were systematically discussed by means of numerical analysis method, and compared with the propagation law of a single material cylindrical shell. Then, the numerical results were verified by means of finite element simulation analysis. Finally, the effect of characteristic impedance of internal and external on the acoustic characteristic of radical phononic crystal was analyzed. So the corresponding parameter influence law was obtained. The results show that the band gap exists in the cylindrical shell of radial phononic crystals, which results in a better sound insulation effect than the single material cylindrical shell in the band gap range, and the inherent characteristics of the structure break through the limitations of the mass law. The surface localized modes phenomenon of the acoustic band gap is determined by the internal and external sound field and structure field.