Optimization and Postbuckling Analysis of Curvilinear-Stiffened Panels Under Multiple-Load Cases

摘要

Recent studies have indicated that panels with curvilinear stiffeners offer a strong potential for structuralntailoring. However, the design complexity requires use of numerical analysis and optimization techniques. Thisnpaper considers the problem of optimal design of a stiffened panel with cutouts and curvilinear stiffeners, undernmultiple-load cases. Multiple failure modes are considered: buckling, damage tolerance, stress, and crippling. Annoptimization framework is presented to minimize mass of the stiffened panel by a combined shape and sizingnoptimization subject to constraints on the individual failure modes. Different panel thicknesses are allowed for eachnregion bounded by stiffeners or panel boundaries. The framework uses Python scripts to couple ABAQUS-basednanalysis with VisualDoc optimization package. A design example is presented to illustrate the capability, and thenoptimized design is compared with that obtained using industry-standard practices. A postbuckling analysis of thenoptimal design with four curvilinear stiffeners is carried out and discussed in detail.