The Method And Software Realization Of Finite Element Model Updating Of Bogie

Platformization and modularization are widely applied in the design of complicated engineering systems,such as modern aircrafts,ships and trains design.Therefore,the original products can be improved only by replacing the corresponding modules,which can greatly save time and money.Accurate finite element model can provide the basis for the dynamic prediction and optimization design of structures.Model updating based on sensitivity analysis has been successfully applied in aeronautics and astronautics,civil engineering and other fields.Engineers adjust model parameters where mostly likely to exist errors according to the results of sensitivity analysis and modeling experience to obtain the finite element model which can accurately simulate the real structure.This paper studies the method of model updating and its software realization in the context of building accurate finite element model of bogie.The main contents are as follows:This paper introduces the theory of model updating based on sensitivity analysis in detail.The sensitivity analysis of the eigenvalues and eigenvectors,the calculation of the residual vectors and the methods to improve the pathological problems are also described in the paper.A finite element model updating software for engineering structures is developed on MATLAB platform.It can call NASTRAN to perform finite element analysis.It combines Matlab's excellent data processing ability and Nastran's excellent finite element analysis ability.GARTEUR is a fully parameterized simulation model.To verify the validity of the model updating method and the practicability of the software,we apply the software to update GARTEUR model under three conditions.The aluminum honeycomb plate is an incomplete parameterized engineering equivalent model,which was updated successively by the original and improved methods.As a result,the latter was shown to produce better results.The force transmission path and connection form of the bogie system are analyzed in detail,and the bogie is divided into four modules.Each module was tested separately,and the modal frequencies and modes of each module were obtained by processing the test data.The characteristics of each module are analyzed and the finite element model is established.The models are updated with the test results as the target.The results show that the updated model can reproduce and predict the test results better.Finally,the modules are assembled into a complete bogie system according to the real connection form and the dynamic analysis is carried out.