Numerical investigation of nonlinear thermomechanical deflection of functionally graded CNT reinforced doubly curved composite shell panel under different mechanical loads

Abstract

In this present study, the geometrical nonlinear static behaviour of the functionally graded carbon nanotube reinforced doubly curved shell panel is investigated under uniform thermal environment. The material properties of the carbon nanotube and matrix are assumed to be graded through the thickness of panel via four types of grading rule. The mathematical model of nanotube graded composite panel is derived using Green-Lagrange type geometrical nonlinearity in the framework of the higher-order kinematics. In addition, thermal environment dependent properties of the individual constituent (carbon nanotube and matrix material) are considered in the present investigation to achieve the generality. Further, the motion equation of equilibrium is obtained by minimizing the total energy functional and discretized with the help of suitable isoparametric finite element steps. The necessary large deflection values are worked out numerically through a generic MATLAB computer code in conjunction with developed nonlinear higher-order model and the direct iterative method. Lastly, the effects of different geometrical and material parameter (aspect ratios, support conditions, thickness ratios, volume fractions, temperature load and type of grading) on the linear and nonlinear deflection behaviour of functionally graded carbon nanotube reinforced composite doubly curved shell panel are examined and discussed in details.