空间桁架结构优化设计
2018-01-13戴一范张淑杰周阳
戴一范++张淑杰++周阳
摘要: 为获得空间桁架结构的合理构型,以某空间设备支撑结构为例,分析结构材料在设计空间的分布形式和桁架结构的传力路径。在已知载荷约束和设计空间大小的条件下,基于连续体拓扑优化方法,以静态多工况刚度和动态固有频率为多目标函数进行优化分析。依据设计要求确定计算模型的结点数和结点位置,获得满足要求的空间桁架结构并进行优化设计。优化结果比原模型质量减少36.7%,一阶模态提高3.6%。
关键词: 桁架结构; 拓扑优化; 多目标; 构型
中图分类号: V19文献标志码: B
Optimization design of space truss structure
DAI Yifan1, ZHANG Shujie1, ZHOU Yang2
(1. School of Aerospace Engineering and Applied Mechanics, Tongji University, Shanghai 200092, China;
2. Shanghai Yuesheng Information Technology Co., Ltd., Shanghai 201100, China)
Abstract: In order to obtain the reasonable configuration of space truss structure, the distribution form of structural material and the transmission path of truss structure are analyzed by taking the supporting structure of space equipment as an example. On the basis of continuum topology optimization method, under the condition that the load constraint and design space size are known, the static multicondition stiffness and dynamic natural frequency are optimized and analyzed as multiobjective functions. According to the design requirements, the node number and node positions of the calculation model are determined, the space truss structure is obtained, and the optimum design is achieved. The final optimization result is that the mass of the original model is reduced by 36.7% compared with the original models, and the first mode is improved by 3.6%.
Key words: truss structure; topology optimization; multiple objective; configuration
收稿日期: 2017[KG*9〗05[KG*9〗17修回日期: 2017[KG*9〗06[KG*9〗28
作者简介: 戴一范(1989—),男,广西平南人,硕士研究生,研究方向为航天器结构优化设计,(Email)08daiyifan@tongji.edu.cn0引言
桁架结构优化设计常用的基结构法[12]以虚拟的初始基结构入手,通过改变杆件结点位置、拓扑连接情况和截面尺寸实现桁架结构的拓扑和布局优化,其最优解是基结构的一个子集,因此合理的结构形式是整个结构优化的基础。AZID等[3]基于遗传算法,提出桁架基结构的自动形成机制,避免传统的基结构法中存在的缺陷;姜冬菊等[4]智能生成形式多样、合理的基结构代替传统优化模型中单一基结构。此类问题的研究大多是针对二维平面桁架的。在特定的载荷和约束条件下,对于三维空间桁架,很难采用定量的方法来描述其结构形式,因此该类研究较少。
本文在已知三维设计空间大小和约束载荷的条件下,基于连续体拓扑优化方法建立优化模型,以多工况下静态刚度和动态固有频率为目标函数,获得结构材料在设计空间的分布形式和传力路径,构造空间桁架的结构构型,并以此为基础进行详细设计。……
