Model Updating And Parameters Uncertainty Analysis On The Locomotive Similar Structure

With the rapid development of high-speed railway, as one of the essential components, thebogie frame structure, can directly carry the body weight and additional load, guide thelocomotive to run along the railroad tracks, and slow down vibration and shock from running. Soits dynamics performance affect the stability, reliability and security of the high-speed railwaylocomotive. Finite element analysis has been widely used in practical engineering problems.However, the precision and credibility of the finite element model always puzzle the finiteelement analysts. During the process, different modeling methods and uncertainty parameterscause the uncertainty of the finite element model analysis. This paper is mainly about the similarstructure of the bogie frame and studies several key technologies and methods oflocomotive bogie similar structure in dynamic analysis. The specific details are as follows:Chinese railway bogie structure studies, based on the modal shape matching principle ofsimilarity theory, combined with CAD software to simplify the structure, can manufacture thesimilar structure model of the bogie frame. Based on the MD_Nastran software and OROS testingequipment, conduct the finite element analysis and experimental research on the similar structureof the bogie frame, and analyse the advantages and disadvantages of several modeling methods.And based on the free-free boundary conditions, study the effect of the supporting mode and thedetecting point on the test, and select appropriate modeling methods and test conditions. Toresolve the big error of the initial finite element model, using MATLAB toolbox, adopt modelupdating based on the sensitivity analysis method. The study selects the optimal results of themodel updating under reasonable correction parameters. Given that there are many pipelines,welding brackets, hangers and other structures distributing on the real frame, this will affect theframe’s mass distribution and also affect the frame itself intrinsic mode and dynamic response.Selecting the modern experimental design method, building the polynomial response surfacemodel, combining Monte Carlo sampling method, using normal distribution algebraic method tostudy the uncertainty forward and reverse estimation problem of the locomotive bogie framesimilar structure and test the precision of uncertainty estimation by contact ratio criterion. Usingdifferent uncertainty quantitative methods, the interval method quantifies the uncertainty to testthe precision of uncertainty estimation by the cumulative probability distribution. In this paper, thestudy of the experiment and the finite element dynamic analysis method on thelocomotive bogie similar structure, provide a guarantee for prediction and reliability estimation indynamic characteristics range on railway industry bogie finite element model and experiment.