基于矩阵逼近的模型修正方法的研究  

RESEARCH OF A MODEL UPDATING METHOD BASED ON MATRIX APPROXIMATION THEORY

作　　者：钱仲焱[1] 冯培恩[1] 

机构地区：[1]浙江大学CAD&CG国家重点实验室,杭州310027

出　　处：《机械强度》2000年第2期100-103,共4页Journal of Mechanical Strength

基　　金：国家自然科学基金重点资助项目! ( 596351 50 )

摘　　要：提出一种新的以试验振动测试和参数辨识的数据为参考 ,进行有限元分析模型修正的方法。该方法基于矩阵最佳逼近理论 ,运用Bayes估计原理来处理试验结果误差带来的试验模态可信度问题 ,求取分析模型对试验获得的不完备模态的谱点的最佳逼近结果 ,最后获得质量阵的最小修正模型。这一方法可以避免非完备模态空间中修正模型可能出现的“畸变”现象 ,能较好体现修正模型的物理意义 ,计算简洁 。A new method for updating FE analytical model is put forward in this paper. In this method,the result data from experimental test and modal parametric identification are used as reference base to refine the analytical model.The optimal approximation is defined as the refinement of FE model with minimum mass matrix change to make the spectrum point of updated model approach to the one coming from the incomplete experimental mode.The optimum matrix approach theory introduced in this method is testified to have the ability keeping the misshapen mode away,which often come up in other incomplete mode updating methods.As another key barrier in practical updating process,the experiment errors are taken into account by making use of Baysian estimation principle.An example of cantilever shows the physical characteristics of this method and the clearness of computation.This method needs no iteration.

关 键 词：模型修正 有限元 谱约束 BAYES估计 矩阵逼近 

分 类 号：TB115[理学—数学] O327[理学—应用数学]