Edge effects in elastic and piezoelectric laminated panels under thermal loading

Abstract

An analytical solution for accurately predicting the edge effects in elastic and hybrid multilayered panels integrated with piezoelectric actuator and sensor layers under thermal gradient loading is presented. The associated thermal problem is solved independently by performing a heat transfer analysis. The extended Reissner-type mixed variational principle is employed to develop the governing equations of the three dimensional (3D) piezothermoelasticity problem. Their solution is obtained using the mixed-field multiterm extended Kantorovich method, developed recently by the author group. The mixed field solution exactly satisfies all the mechanical and electric boundary conditions pointwise, leading to an accurate solution. The formulation is general, and is applicable for composite, sandwich and hybrid panels with arbitrary lay-up and boundary conditions. The solution is validated against the exact 3D solution available for simply supported panels. The free edge stress field in sandwich and hybrid composite laminates is investigated under uniform as well as gradient thermal loading. The solution successfully captures the singularity in free edge interlaminar stresses. The significance of pyroelectric coupling on the free edge thermal stress field is investigated, and the feasibility of its control through electric field actuation is examined.