Wave propagation in layered piezoelectric rectangular bar: An extended orthogonal polynomial approach

•We extended the orthogonal polynomial series approach to 2D waveguides.•We initially investigated waves in layered piezoelectric rectangular bar.•The width to height ratio and stacking sequence significantly influence the wave characteristics.•High frequency waves mostly propagate in the layer with a lower wave speed.

Wave propagation in multilayered piezoelectric structures has received much attention in past forty years. But the research objects of previous research works are only for semi-infinite structures and one-dimensional structures, i.e., structures with a finite dimension in only one direction, such as horizontally infinite flat plates and axially infinite hollow cylinders. This paper proposes an extension of the orthogonal polynomial series approach to solve the wave propagation problem in a two-dimensional (2-D) piezoelectric structure, namely, a multilayered piezoelectric bar with a rectangular cross-section. Through numerical comparison with the available reference results for a purely elastic multilayered rectangular bar, the validity of the extended polynomial series approach is illustrated. The dispersion curves and electric potential distributions of various multilayered piezoelectric rectangular bars are calculated to reveal their wave propagation characteristics.