摘要
薄膜结构在航天工程中有广泛的应用,但其在真空环境与空气环境下的模态特性有较大差异。由于试验设备及仿真模态识别方法的限制,现有文献中同时包含薄膜结构在真空环境与空气环境下的模态测试仿真及试验较少,并且对于仿真与试验方法一致性的对比研究也较少。因此,介绍了所制备的低真空试验装置,随后通过仿真算例对比了仿真中通常采用的Lancoz法与试验中通常采用的随机子空间法(Stochastic Subspace Identification,SSI)识别到的薄膜前4阶模态,结果显示,两种方法具有良好的一致性。将仿真算例结果与试验结果进行对比,低真空环境下仿真与试验有良好的对应关系,但空气环境下识别到的频率有差异,且会随着膜的厚度增加而逐渐降低。通过仿真分析讨论了观测点数目及激振器振幅对模态识别结果的影响。
Membrane is a widely used structure in aerospace engineering,but its modal characteristics in the vacuum and air environment are quite different.Due to the limitations of test equipment and simulation modal identification methods,there is less literature including both simulation and experiment of membrane structures in both vacuum and air environments simultaneously,and there are few comparisons between the modal identification methods of the above simulation and experiment.Therefore,a low vacuum experiment device was introduced firstly.Then the first four modals of a membrane identified by the Lancoz method and a stochastic subspace identification(SSI)method were compared.The results show that the two methods have fine consistency.Moreover,these results were compared with the experiment results.The simulation and experiment have a good correspondence in the vacuum environment,but in the air environment the frequencies are different,and the deviation decreases as the thickness of the membrane increases.Finally,the effects of the number of observation points and the amplitude of the exciter on the modal identification results were discussed through simulation analysis.
作者
张祎贝
陈务军
邓小伟
余征跃
谢超
彭福军
ZHANG Yibei;CHEN Wujun;DENG Xiaowei;YU Zhengyue;XIE Chao;PENG Fujun(Space Structure Research Center,Shanghai Jiao Tong University,Shanghai 200240,China;Department of Engineering Mechanics,Shanghai Jiao Tong University,Shanghai 200240,China;Aerospace System Engineering Shanghai,Shanghai 201108,China)
出处
《振动与冲击》
EI
CSCD
北大核心
2020年第20期168-174,182,共8页
Journal of Vibration and Shock
基金
载人航天预先研究项目(040203)。
关键词
薄膜结构
真空环境
空气环境
模态识别
低真空试验装置
membrane structure
vacuum environment
air environment
modal identification
low vacuum device
