某航天装置的动态特性分析及结构修改

Analysis on Dynamic Characteristics and Structural Modification of a Spaceflight Assembly

目的研究某航天装置的振动特性和动力响应特性,为其结构振动预测、动力学结构的修改与设计提供理论依据。方法利用有限元软件MSC.Patran/Nastran建立该航天装置的有限元模型,进行模态分析和频率响应分析,并与试验测量结果进行了比较,两者基本相符。根据模态分析和频率响应分析结果对该航天装置的薄弱环节进行修改。结果有限元分析和试验相比频率误差在3.1%以内,加速度响应误差在11.9%以内,说明有限元模型的模拟形式是准确的。修改后结构的响应降低了50%左右。结论该方法为复杂结构振动特性分析提供了可行的技术途径,缩短了研制周期、降低了成本。

Objective To study the vibration characteristics and the dynamic response of a spaceflight assembly which pravides theoretic basis to forecast its structural vibration and modify its dynamics structure. Methods The finite element model of the assembly was established. Its modal and frequency response were analyzed by software MSC. Patran / Nastran, and compared with test data. They were closed each other. The structure of the assembly was modified base on the result of modal and frequency response analysis. Results The errors between the finite element analysis and test data were less than 3.1% （frequency） and 11.9% （ acceleration response values） ,which showed that the method of simulation of the finite element model was correct. The acceleration response values descended around 50% after structural modification. Conclusion A feasible technical way to analyze dynamic characteristics of complex structure is provided, which can shorten the development period and descend the design cost.