Research And Optimization On Dynamic Characteristics Of Bogie Frame

With the continuous improvement of the train speed,the service condition of components of the train becomes more and more severe,therefore,the influence of train dynamic performance is more and more obvious.Bogie is one of the most important load-bearing components in train operation,which is the key component to ensure the safe operation of high-speed vehicles.In this paper,taking a high-speed bogie frame as the research object,the dynamic performance of the bogie frame is analyzed and optimized,which combine running test and finite element analysis.Firstly,the working modal parameter of the bogie frame is identified by polymax,which is based on running test.The identified results are verified by the modal assurance criterion.The identification results of the working modal parameters can be used to verify the finite element model,providing a reasonable basis for the study of the dynamic performance of the bogie frame.Secondly,the finite element analysis model is created to calculate the unconstrained mode and constraint mode of the bogie frame.Through the comparison of the calculated mode and the working mode,the accurate finite element model is obtained.Analysis for the weak position of the frame based on modal strain energy.The influence of motor excitation and track excitation on the vibration of the bogie frame is analyzed by harmonic response analysis.Based on the amplitude-frequency characteristic curve of the weak position,the resonance frequency of the weak position is found out.Finally,the sensitivity of each component of the bogie frame is analyzed and the design variables are determined by the results of sensitivity analysis.Under the condition that the quality of the frame is not increased,the size optimization of the bogie frame is carried out with the aim of maximizing the first-order natural frequency and fixed frequency of the bogie frame.The static strength and fatigue strength of the optimized bogie frame are analyzed,confirming the optimized structure meets the design requirements.Under the premise of meeting the strength requirements,The first-order natural frequency and the dynamic performance of the bogie frame are improved.