Numerical investigation into dynamic behaviors of axially moving functionally graded porous sandwich nanoplates reinforced with graphene platelets

Abstract

This paper aims to study the nonlinear transient response of a moving porous sandwich micro-size plate strengthened with graphene platelets (GPLs) under two types of distributed dynamic forces, a pulse load and an impact load. To model closed cell cellular solids stiffened with graphene platelets (GPLs), Gaussian-Random field scheme along with Halpin-Tsai model for microsystems are used, through which mechanical properties of the structures can be obtained. On the basis of the first order shear deformation and von Karman nonlinear theories, the dynamic equations are extracted, and then nonlocal strain gradient theory is recruited to consider small size effects due to non-uniform stress and strain fields. Subsequently, using a hybrid method, kinetic dynamic relaxation technique in conjunction with Newmark’s direct integration method, the time-dependent equation sets are solved. Finally, effects of some key factors such as porosity and GPL coefficients and dispersion patterns, nano-system parameters and the velocity of moving nanoplate on time history of deflections are considered. The results show that as the values of the nanoplate velocity increase, the importance of nonlocality and strain gradient parameter on dynamic deflections become more outstanding. The results can be used to design novel components in marine vessels in nano-scale.