Analysis of the band gap characteristics of a new type of three-dimensional single phase phononic crystal

Abstract

A novel three-dimensional single-phase phononic crystal is proposed. Compared with the traditional multi-component three-dimensional phononic crystal, the single-phase phononic crystal has a low broadband gap, a single structure material, and a stable and portable structure. COMSOL software was used to calculate the band structure, vibration mode and transmission characteristics of single cell. Change the material parameters and structural parameters of the structure to study the change of energy band. The results show that there are five complete band gaps in the frequency range of 0–2400 Hz, and the low frequency range forms a broadband gap with a relative bandwidth of more than 0.7. The low band gap is mainly caused by the coupled vibration of scatterers, while the high band gap is mainly affected by the matrix frame. The thicker the scatterer, the lower the overall band gap, the easier to form a low broadband gap; By changing the material parameters, the normalized frequency of the first complete band gap of the structure remains within 0.1. The range and width of the band gap can be controlled by adjusting the scatterer. The designed structure is suitable for low frequency vibration and noise reduction.