摘要
为适应光学红外望远镜口径不断增大的需求,降低驱动功率,应用碳纤维复合材料对望远镜主镜室桁架进行轻量化设计。对望远镜主镜室碳纤维复合材料桁架单元铺层进行优化设计,利用进化算法选取最优铺层方案。对望远镜主镜室桁架单元建模,并利用敏感性分析及进化算法选取最佳铺层方案,设计另外3种典型铺层方案进行对比,对桁架杆单元进行静力学分析和加载实验,对桁架杆组装成的六杆三棱锥单元进行模态分析和振动测试。有限元分析和实验结果对比表明:最优铺层方案为[±45°/90°/0°/90°/0°]s。有限元分析得到该方案桁架杆单元的等效轴向刚度为8.306×10^(6)N/m,实验测得为7.463×10^(6)N/m;有限元分析得到的等效径向刚度为3 968.3 N/m,实验测得为3 344.5 N/m。该方案六杆三棱锥单元模态分析得到一阶频率为93.699 Hz,振动测试测得一阶频率为84.683 Hz。复合材料桁架杆质量比同尺寸的钢结构杆减轻了77.6%,静力学性能与动力学性能均优于同质量钢杆。最佳铺层方案的有限元分析结果和实验结果表明其静力学性能及动力学性能均优于其他方案。
To meet the increasing demand of optical infrared telescopes and reduce the driving power,car⁃bon fiber composite materials are used to carry out lightweight research on the main mirror truss of the tele⁃scope.The layout of carbon fiber composite truss element in the telescope's primary mirror chamber was optimized,and the evolution algorithm was used to select the optimal layout.The truss element of the telescope's primary mirror chamber was modeled,and the sensitivity analysis and evolution algorithm were used to select the best layup scheme.Three typical layup schemes were utilized for comparison.Static analysis and loading experiment are performed on the truss rod element.The six-bar triangular pyramid unit assembled by the rods is subjected to modal analysis and vibration test.The comparison of finite ele⁃ment analysis and experimental results show that the optimal layup plan is[±45°/90°/0°/90°/0°]s.The equivalent axial stiffness obtained by the finite element analysis of the truss bar element of this scheme is 8.306×10^(6) N/m,and the experimental measurement is 7.463×10^(6) N/m;the equivalent radial stiffness obtained by the finite element analysis is 3968.3 N/m,and the experimental measurement is 3344.5 N/m.The modal analysis of the six-bar triangular pyramid element of this scheme shows that the first-or⁃der frequency is 93.699 Hz,and the first-order frequency is 84.683 Hz measured by the vibration experi⁃ment.The weight of the composite truss rod is 77.6%lighter than the steel structure of the same size,static and dynamic properties are better than steel rods of the same weight.The results of finite element analysis and experimental verification of the best layup scheme indicate that its static and dynamic proper⁃ties are better than other schemes.
作者
顾伯忠
陈萌
乐中宇
GU Bo-zhong;CHEN Meng;YUE Zhong-yu(National Astronomical Observatories/Nanjing Institute of Astronomical Optics&Technology,Chinese Academy of Sciences,Nanjing 210042,China;Key Laboratory of Astronomical Optics&Technology,Nanjing Institute of Astronomical Optics&Technology,Chinese Academy of Sciences,Nanjing 210042,China;University of Chinese Academy of Sciences,Beijing 100049,China)
出处
《光学精密工程》
EI
CAS
CSCD
北大核心
2021年第9期2116-2125,共10页
Optics and Precision Engineering
基金
国家自然科学基金资助项目(No.11703057)。
关键词
光学望远镜
主镜室桁架单元
碳纤维复合材料
进化算法
优化设计
optical telescope
primary mirror chamber truss unit
carbon fiber composite
evolution algo⁃rithm
integrated optimization
