Optimization of Curvilinearly Stiffened Panels with Single Cutout Concerning the Collapse Load

Abstract

The motivation of this study is to meet the requirement of cutout reinforcements in aerospace industry by using the design flexibility of curvilinearly stiffened panels. The reason is that the load path and tension field caused by curvilinear stiffeners can increase the load-carrying capacity of stiffened panels. The inherent superiority of such structures was examined in detail by comparison with those having straight stiffeners. Due to the large computational burden caused by post-buckling analysis, the optimum design of curvilinearly stiffened panels with single cutout was obtained based on surrogate model. On this basis, variable symmetrization and reduction methods were developed for different design cases, aimed at reducing the number of dependent variables in the optimization. Illustrative examples show the superiority of curvilinearly stiffened panels for cutout reinforcement, and demonstrate the effectiveness of the proposed optimization framework.