Thermal Buckling and Flutter Behavior of Shape Memory Alloy Hybrid Composite Shells

Abstract

A new nonlinear finite element formulation is presented to predict the thermal buckling and flutter boundaries of shape memory alloy hybrid composite cylindrical panels at elevated temperatures. The governing equations are obtained using Marguerre curved-plate theory and the principle of virtual work. The effect of large deflection is included in the formulation through the von Karman nonlinear strain-displacement relations. To account for the temperature dependence of material properties, the thermal strain is stated as an integral quantity of the thermal expansion coefficient with respect to temperature. The aerodynamic pressure is modeled using the quasi-steady first-order piston theory. The Newton-Raphson iteration method is employed to obtain the nonlinear thermal postbuckling deflections, and a frequency-domain solution is presented to predict the critical dynamic pressure at elevated temperatures. Numerical results are presented to illustrate the effect of shape memory alloy fiber embeddings, temperature rise, height-to-thickness ratios, and boundary conditions on the panel response.