Analysis and Optimization of Composite Kagome Grid Panels Subjected to the Low Velocity Impact

Abstract

By the present paper, an optimal volume technique of stiffened laminated panel subjected to Low Velocity Impact (LVI) is developed using an analytical model that couples a genetic algorithm optimization technique. Using the first-order transverse-shear deformation theory (FSDT) for anisotropic plates, the stiffness of the Kagome grid stiffeners and the plate are estimated by considering both effects of moments and forces in a basic repetitive cell. Where, the stiffness of the equivalent plate is computed by superposing stiffness the plate and Kagome stiffeners. The contact impactor/panel is idealized by the mass/spring model. The convergence of the impact force and the transverse displacement response at the contact point are plotted. Using the genetic algorithm (GA), the minimization of the panel volume is achieved in two stages. In the first stage, the design variables are the mechanical properties of the equivalent plate and the impactor. But, in the second stage, the stacking sequences were considered as design variables. Finally a parametric study is made and major conclusions are deduced regarding to the panel volume, time and impact velocity on behavior of the stiffened panel. The results show that the increase in stiffeners thickness is traduced by smaller transverse displacement involving a better impact performance, best optimization and panel integrity.