Investigation of phononic band gap structures considering interface effects

Interface imperfection has a significant effect on the wave׳s propagation behavior in the phononic crystals. To account for the interface imperfection, a numerical simulation based on the boundary element method has been proposed to investigate the propagation of in-plane waves in the phononic crystals with imperfect interfaces. The effects of interface spring stiffness, volume fractions, density ratio, and the shape of the scatters on the band gaps are analyzed. It can be concluded that slightly interface imperfection would not affect band structures too much. However, when the interface is relatively weak, the effect of interface imperfection cannot be neglected.