浮筏筏架模态测试及模型相关性分析

Modal Testing and Model Relativity Analysis of Raft Frame

用有限元法计算浮筏隔振系统的中间筏架其前五阶模态,并通过模态测试测得其模态,再采用LMSVirtual lab对此筏架有限元模型和测试模型进行相关性分析,从分析得到的模态置信度可以看出用有限元法计算的模态基本准确。

The paper intends to analyze quantitatively the correlation between the NASTRAN finite element （FE） model and a testing model for a middle raft frame of a floating-raft isolation system. The first five vibration modes of the raft flame are estimated by finite element method （FEM） and measured by testing. The modal assurance criterion （MAC） matrix is established in LMS virtual lab for relativity analysis between the FE model and the testing model. The MAC estimated by LMS virtual lab shows that the modal computed by FEN is basically correct and the method can he used for dynamic response analy- sis of the structure.