The Schoch effect mechanism analysis and its regulation of two dimensional three components phononic crystal

Abstract

In this paper, through changing the phononic crystal surface and adjusting the structure of surface layer, we observed the Schoch effect of two dimensional phononic crystal, and the Schoch shift reached 7.1 times of the lattice constant. To further understand the physical mechanism of this kind of phenomenon, the finite element method is used to calculate the band structure of the model. Because of the influences of the surface of structure, there exists a kind of waveguide mode in the passband. Through careful analysis of the band structure and the sound pressure field profile, it is found the kind of waveguide mode makes the incident wave energy go into the waveguide layer which resulting in reflection beam deformation and offset. In addition, through the finite element simulation, the change regulation of the Schoch shift in the phononic crystal is studied by changing the radius of the surface layer and further increase the layer number of the surface layer of the phononic crystal to achieve the control of the Schoch effect of the phononic crystal. The conclusion of this paper can provide some theoretical reference and give some guidance for the design of acoustic sensors based on Schoch effect.