Wave propagation in an FGPM sandwich plate with an NPR core submerged in a fluid medium

In this study, wave propagation in a submerged sandwich plate with a negative Poisson’s ratio (NPR) core, was investigated. The sandwich plate consists of three parts: two functionally graded piezoelectric material (FGPM) skins at the top and bottom and an NPR core in the middle. Using Hamilton’s principle, the equations of motion for wave propagation in the FGPM sandwich plate with an NPR core were derived, and the dispersion relations were obtained. The effects of the geometric parameters, gradient index, fluid density and depth, wave number, and NPR core parameters on the wave frequency and the phase velocity were analyzed. Results show that presence of fluid leads to a reduction in the phase velocity of the sandwich plate. The results will be useful in the design of structures submerged in fluid environment.