Series solutions for free in-plane vibration of composite plates with arbitrary shape

In this paper, we present a series solution for free in-plane vibration of composite plates with arbitrary shape by using the domain segmentation integral method and derive the tangential and normal vibration displacement equations for the plate boundaries. The solution presented is widely applicable to the analysis of free in-plane vibration of plates; it can accurately and effectively solve the in-plane free vibration problem of arbitrarily shaped non-homogeneous orthotropic plates of variable thickness, complex geometry and variable material properties with respect to in-plane coordinate parameters. To verify the effectiveness, accuracy and applicability of the proposed solution, we perform a computational analysis of different orthogonalization intervals, weight functions, penalty stiffness and the truncation number of orthogonal polynomials. Additionally, the effects of the parameters of thickness and nonhomogeneity on the in-plane vibration characteristics of plate are studied. As a result, we present a new series of natural frequencies and mode shapes for arbitrarily shaped non-homogeneous orthotropic plates of variable thickness.