摘要
天线有限元模型与实际天线往往存在结构参数误差和材料参数误差等,使有限元模型不能真实反映实际天线结构在各种载荷下的变形特性.针对亚毫米波天线,提出了亚毫米波天线有限元模型参数修正复合优化方法.该方法包括3步,第1步建立天线参数化有限元模型,并进行参数灵敏度分析;第2步,以第1步中得到的高灵敏度参数为优化变量建立优化函数,以初始模型与假想实际天线变形特性的差值最小为目标进行优化;第3步,基于零阶优化法和一阶优化法对天线有限元模型进行复合优化,使天线有限元模型逐渐逼近实际天线.为验证所提出参数修正优化方法的可行性,针对一台1.2 m亚毫米波天线,将对其进行假想实验获得的变形特性作为优化目标,分别对多个材料参数在不同的载荷工况下进行优化,结果表明天线有限元模型经过参数优化后与假想实际天线一致,证明了所提出的亚毫米波天线有限元模型参数优化修正方法可行,并在重力载荷下对修正优化后的天线模型的变形规律进行分析.这种优化方法可以推广应用到大口径亚毫米波天线的有限元模型修正中.
There are some structural parameter errors and some material property errors between the Finite Element Model(FEM)and the Real Structure of Antenna(RSA).Because of these errors,the FEM can not realistically reflect the RSA performance under various loads.In this paper,a parameter compound optimization method is proposed for updating the submillimeter-wave antenna finite element model.The method consists of three steps.Firstly,the parametric finite element model of the antenna is created,and the sensitivity analysis is carried out.Secondly,establish the objective function.The performance of the imaginary RSA is chosen as the optimization object,and the high sensitivity parameters act as the optimization variables.The performance of the FEM before optimization is chosen as the initial value.Thirdly,the compound optimization is carried out based on the zero-order method and the first-order method.In order to verify the feasibility of the parameter compound optimization method of the FEM updating,we take the 1.2 meter submillimeter-wave antenna as research object and optimize it respectively under different loads for various material property parameters.The results show that the performance of the FEM is identical to that of the imaginary RSA after the parameter compound optimization.Thus,the feasibility of this method has been proven.Besides,based on the updating model of the antenna,the deformation regularities are analyzed under gravity load.Moreover,the method could also be applied to update the large aperture submillimeter-wave antenna finite element model.
作者
张明珠
王海仁
左营喜
ZHANG Ming-zhu;WANG Hai-ren;ZUO Ying-xi(Purple Mountain Observatory,Chinese Academy of Sciences,Nanjing210034;School of Astronomy and Space Science,University of Science and Technology of China,Hefei230026;Key Laboratory for Radio Astronomy,Chinese Academy of Sciences,Nanjing210034)
出处
《天文学报》
CSCD
北大核心
2019年第4期41-58,共18页
Acta Astronomica Sinica
基金
国家重点研发计划(2018YFA0404702)
国家自然科学基金项目(11773084、11873100)
中国科学院青年创新促进会人才项目(2019315)
中国科学院天文台站设备更新及重大仪器设备运行专项资助
关键词
亚毫米波天线
有限元模型修正
材料参数优化法
submillimeter-wave antenna
finite element model updating
material parameters optimization
