基于改进模拟退火算法的复合材料层合板频率优化

针对复合材料层合板频率优化问题,结合可行规则法和直接搜索模拟退化算法,提出了一种自适应模拟退火(SA)改进算法。层合板优化目标是基频、频率带隙以及给定基频和带隙约束的层合板厚度。设计变量包括铺层角度和铺层数两种离散变量。改进算法的自适应新点产生模块采用依赖温度的动态调整搜索半径,改善了直接搜索模拟退化(DSA)算法易陷入局部极值的缺陷,而可行规则法的引入提高了SA算法求解约束问题的效率和简易性。采用Ritz法进行频率响应分析以考虑弯扭耦合影响。不同铺层数、角度增量和长宽比时的层合板3类算例结果显示:改进算法能有效求解层合板频率优化,可获得更多或更好的铺层顺序全局优化解。

Frequency optimization of composite laminates using an improved simulated annealing algorithm

An improved adaptive simulated annealing(SA) algorithm, which combined with the feasibility based rule and direct search simulated annealing, was proposed to optimize the frequency characteristics of composite laminates. The optimization goals of laminates are fundamental frequency, frequency band gap and laminate thickness of band gap constraint. The discrete design variables include fiber orientation angles and the layer number. A new point generation mechanism with the dynamic variation search radius improves the drawback of the direction simulated annealing (DSA) algorithm easy to fall into local minima. Introducing the feasibility based rule into SA enhances the efficiency and simplicity of solving constrained problem. Accounting for bending-twisting coupling effects, the Ritz method was employed to calculate the laminate frequency response. Three types of examples of design symmetrically composite laminates with various layer numbers, angle increment and aspect ratios were conducted. Numerical results indicate that the present improved simulated annealing algorithm can effectively solve laminates frequency optimization and provide with more or better global optimum solutions for the stacking sequence.