Active vibration suppression of tetrachiral auxetic core sandwich panel with CFRP skin: An RVE homogenization-assisted finite element approach

Abstract

Free vibration as well as the controlled dynamic response of moderately-thick smart sandwich panel are numerically explored considering the size effect of chiral unit cells at the microscopic level, with the help of RVE-assisted-finite element (FE) approach. In this scientific article, the authors have made a debut attempt to analyse the smart damping behaviour of a tetrachiral-type auxetic core sandwich panel (with carbon/epoxy skin) deploying a real-time based constant velocity feedback controller in a closed loop configuration. Effective anisotropic elastic properties as well as the reduced stiffness matrix of the cellular core layer have been determined by using RVE-FE based full-scale homogenization technique in ANSYS® platform. Dynamic equation of motion governing the plate structure, has been derived using an energy-based variational principle, and further solved with the help of a quadratic interpolation based finite element method. The mid-plane kinematics of the plate structure are assumed to follow first order shear deformation theory (FSDT). A number of numerical examples have been solved and compared with previously published literature to ensure the consistency of the present homogenization-cum-numerical approach. From the observation it is found that, the natural frequency and the controlled dynamic response of tetrachiral-type sandwich structure are very much sensitive towards the geometry (cell wall thickness, ligament length etc.) and architecture of the unit cell of the auxetic core. Also, a comparison study has been performed between tetrachiral auxetic smart sandwich and regular hexagonal honeycomb smart sandwich plate, which confirms about the mechanical advantage of the former over the later configuration, due to the existence of out-of-plane negative Poisson's ratio (NPR) and axial-shear coupling stiffness. Afterwards, a few additional numerical examples have been solved by changing different influencing parameters of the auxetic core sandwich plate and important results are reported in the article.