Nonlinear thermal free vibration frequency analysis of delaminated shell panel using FEM

Abstract

The current research reported the thermal free vibration characteristics of the debonded composite shell structure considering the large geometrical deformation. The delaminated composite panel structural model is derived using two different higher-order polynomial kinematics. The nonlinear structural geometry has been modeled via Green-Lagrange relations in conjunction with temperature loading. The separation between the adjacent layers of the composite has been incurred through a sub-laminate approach and the corresponding displacement continuity imposed at the boundaries (laminated and delaminated). Moreover, the isoparametric Lagrangian type of element (eighty-one and ninety degrees of freedom) is adopted for the discretization of the physical shell structure. The nonlinear governing equation of motion of heated shell (healthy and debonded) structure derived using Hamilton principle and the nonlinear frequency responses computed using the direct iterative technique for the computational purpose. The solution (numerical) stability and the accuracy have been established as a priori by solving a series of examples available in the literature. The conclusions regarding the model applicability for debonded (size, location and position) structural analysis represented with or without temperature effect.