共固化粘弹性复合材料的结构多目标进化优化设计

Multi-Objective Evolutionary Optimization Design of Composite Structure Embedded with Cocured Viscoelastic Layers

共固化粘弹性复合材料结构兼具结构承载和阻尼减振能力,设计时需同时考虑强度、刚度、质量和阻尼性能等指标要求,且设计变量众多,因此传统的设计方法难以实现结构的优化设计。本文建立了共固化粘弹性复合材料结构的多目标优化模型,优化目标为结构质量最小化和模态损耗因子最大化,设计变量包括铺层厚度、方向角和阻尼层厚度,并考虑结构动刚度的约束条件。阻尼结构的分析采用基于有限元法的模态应变能法,进化优化采用改进的非支配排序多目标遗传算法(NSGA-II)。最后的优化算例表明将多目标遗传算法应用于共固化粘弹性复合材料结构阻尼/结构一体化设计的可行性。

It＇s difficult for traditional design methods to achieve the optimization design of composite structures embedded with cocured viscoelastic layers,because their strength,stiffness,mass and damping characteristic must be taken into account simultaneously and there are too many design variables.Taking structure mass and modal damping factor as two optimized objectives,a multi-objective optimization model is developed.Design variables include ply thickness,ply orientation angle and viscoelastic layer thickness.Constraints are imposed on modal frequencies.A finite element method-based modal strain energy method is selected to calculate the modal damping factor.An improved nondominated sorting genetic algorithm（NSGA-II） is selected as the multi-objective optimization algorithm.Finally,two test cases are optimized.The results show that the multi-objective evolutionary optimization can be used as effective design method for the composite structure embedded with cocured viscoelastic layers.