Suppression of nonlinear aeroelastic responses of graphene platelet-reinforced composite lattice sandwich plates using a nonlinear energy sink

In this study, a nonlinear energy sink (NES) is used to suppress the nonlinear aeroelastic response of graphene platelet reinforced composite (GPLRC) lattice sandwich plates in a supersonic airflow for the first time. The face sheets and lattice core trusses of lattice sandwich plates were reinforced with graphene platelets (GPLs). The effective elastic modulus of the GPLRC was solved using the Halpin–Tsai micromechanical model, and Poisson's ratio, mass density, and coefficient of thermal expansion were calculated using the rule of mixtures. Kirchhoff plate and first-order shear deformation theories were used separately to model the face sheets and lattice core layer of the structure. The nonlinear strain–displacement relationship was derived using the von Karman large-deformation theory. The aerodynamic load was simulated using the piston theory. The motion equations of the supported GPLRC lattice sandwich plates with an NES under supersonic flow were derived using the Lagrange equation and the assumed mode method. The nonlinear aeroelastic responses of the GPLRC lattice sandwich plate system coupled with an NES were solved using Newmark direct integration combined with the Newton–Raphson iteration technique. Finally, a detailed study of the effects of the NES on the suppression of the flutter behavior of GPLRC lattice sandwich plates was carried out. The results showed that within specific mass, damping, and nonlinear stiffness ranges, the NES could effectively suppress the nonlinear aeroelastic response of the GPLRC lattice sandwich plates.