双向固定网格渐进结构优化方法

Bi-directional Fixed Grid Evolutionary Structural Optimization Method

近年来发展的渐进结构优化方法是一种有前途的结构拓扑和形状优化方法。本文在渐进结构优化方法的框架内建立了统一敏感度的概念,并基于固定网格有限元技术,发展了一种新的增加材料技术,提出了双向固定网格渐进结构优化方法。将该方法应用于复合材料壳结构开孔形状优化,以孔周等Tsai-Hill强度值作为优化目标,可以得到合理的最优解,证明了双向固定网格渐进结构优化方法的适用性。不同的初始点能得到几乎相同的最优解,展示了本文方法良好的全局最优性。

Evolutionary structural optimization (ESO) method proposed in the last decade is promising in engineering shape and topology design. Based on a fixed grid finite element framework and universal sensitivity in all design regions, a novel bi-directional evolutionary optimization technique, ie., FG BESO, is developed here. A uniform Tsai-Hill index criterion is presented to evaluate stress concentration around the cutout boundary. The FG BESO method is then applied to optimize the cutouts shape in laminated composite shells, and the example demonstrates the capability of FG BESO for solving cutout design problems in curved shells, whose capability of reducing the dependence of the optimal results on initial design is sufficiently manifested to achieve the global optimum.