Nonlinear aeroelastic analysis of temperature-dependent graphene platelet-reinforced composite lattice sandwich plates under general boundary conditions

In this study, the nonlinear aeroelastic properties of graphene platelet-reinforced composite (GPLRC) lattice sandwich plates under general boundary conditions in supersonic airflow is investigated for the first time by considering temperature-dependent properties. Face sheets are reinforced with graphene platelets (GPLs) uniformly or linearly distributed in the thickness direction. Similarly, the lattice core trusses are reinforced with GPLs. The Halpin-Tsai model is used to calculate the effective elastic modulus of GPLRCs; Poisson's ratio, mass density, and thermal expansion coefficient are determined by the rule of mixture. The face sheets and lattice core layer are modeled separately using the Kirchhoff plate and first-order shear deformation theories. The nonlinear strain-displacement relationship is derived by the von Karman large deformation theory. The aerodynamic load on the structure is expressed by the piston theory. The motion equations of are calculated using the Lagrange equation. Fourier series combined with auxiliary functions is used to describe the displacement components of sandwich plates. The Newmark direct integration combined with the Newton-Raphson iteration technique is employed to solve the nonlinear aeroelastic response. Finally, the influences of boundary condition, thermal load, GPL distribution pattern, and weight fraction, on the nonlinear aeroelastic properties of lattice sandwich plates are analyzed in detail.