Lamb wave band gaps in a homogeneous plate with inclined cylindrical dots

Abstract

We report on the theoretical analysis of locally resonant sonic band gaps (BGs) in a phononic crystal (PC) structure constituted by a square array of inclined cylindrical dots deposited on a thin homogeneous plate. Based on an efficient finite element method (FEM), we show that the PC plate with inclined dots can lower Lamb wave BGs due to a weak localized resonance of the edge of the upper surface of the inclined dots. The BGs can be effectively shifted by changing the value of the incline. The total displacement fields are computed to explain how the inclined dot induces the lowering of the locally resonant BGs. Transmission power spectra (TPS) are calculated to demonstrate the existence of the BGs and it matches well with the band structure. BGs evolution as a function of geometrical parameters of the PC plate with inclined dot is also studied.