基于有限元分析的复杂结构弹性振动传递函数建模  

Transfer function modeling for elastic vibration of complicated structures based on finite element analysis

作　　者：武新峰[1] 雷勇军[1] 李家文[1] 

机构地区：[1]国防科学技术大学航天与材料工程学院,长沙410073

出　　处：《振动与冲击》2012年第11期57-61,77,共6页Journal of Vibration and Shock

基　　金：教育部新世纪优秀人才支持计划(NCET-08-0148)

摘　　要：为了解决复杂结构的弹性振动建模问题,提出了一种基于有限元分析的弹性振动传递函数建模方法。首先建立能够准确反映结构动力学特性的有限元模型;然后根据输入参数和辨识算法类型的不同,分别从时域和频域两方面进行传递函数建模,其中时域辨识建模以PRBS信号的瞬态响应结果为辨识数据进行时域参数辨识,频域辨识建模以结构的频率响应函数为辨识数据进行频域参数辨识;最后以"时域建模频域验证,频域建模时域验证"的方法检验传递函数的精度。通过建立悬臂梁、某运载火箭和某弹体局部结构的传递函数模型,证明了该方法的可行性和有效性,为该方法在工程实践中的应用提供参考。A new methodology to solve transfer function modeling for elastic vibration of complicated structures was presented. Based on dynamic analysis of a refined finite element model for a structure, the transfer function model was established both in time domain identification and frequency domain one. The transient response results to PRBS excitation were used for the identification of the transfer function model gained in time domain and the frequency response function data were used for that in frequency domain. The precision of the model could be verified with two results in different domains each other. At last, an example of a cantilever beam indicated that the proposed method is feasible and effective. Further, the transfer function models for a rocket and a missile＇s .local structure were established to offer a valuable reference for engineering application.

关 键 词：有限元分析 弹性振动 传递函数 参数辨识 

分 类 号：V42[航空宇航科学与技术—飞行器设计]