Research On Structural Reliability Of Key Parts Of EMU Bogie Frame Under High Frequency Excitation

With the continuous development of the length and speed of High-speed railway,rail corrugation,the rail-gap impact,wheel polygonization phenomena and other reasons might cause high-frequency excitation that could cause the vibration of the high-speed train and increase the dynamic stress of the high-speed train,which will seriously affect the overall comfort and safety of the high-speed train.Therefore,the bogie frame plays a very important role in the safe operation of the whole high-speed train,because it is the most crucial load-bearing component.This thesis would concentrate on bench tests and rigid-flexible coupling simulation based on the bogie frame of tow trailer of CR400 BF.This paper is mainly as follows:(1)Based on the bogie frame of trailer of CR400 BF,the study carried on measuring-point arrangement and formulation of high frequency vibration bench test.Furthermore,the high frequency vibration bench test was carried out under different polygon amplitude,polygon series and end structure of different frames.Then,the dynamic stress data of the key parts of the frame are obtained through data processing and analysis.(2)According to the outcomes of high frequency data,the paper analyzed the dynamic stress of each part of the frame of 37-sides wheel and 20-sides wheel under different working condition of incentive based on test bed of small roller wheel.Then,this article would find out the typical measuring point of area of strong stress response,obtain the stress-time history curve varies with the velocity based on the time-domain analysis,obtain the vibration frequency of the key region subjected to forced vibration at the higher stress velocity stage through frequency domain analysis,analyze the stress characteristics of the measuring point and the relationship between the natural frequency and the excitation frequency combining with the natural frequency of the measuring point obtained from the frequency sweeping test.Finally,the paper would infer the conclusion that the main reason for the increase of the dynamic stress of the measuring point is the resonance of coincidence of the main frequency of the vibration of the measuring point and the natural frequency of the measuring point.(3)With the modal stress recovery method and obtain rigid-flexible coupling dynamics model based on ANSYS and SIMPACK,the paper analyzed The stress-time history of the frame of the 20-sides wheel with different speed levels,compared analysis data with experimental data and verified the validity of the simulation model.(4)This article would assess damages of frame with Dirlik method,calculate the damage of key measuring-points of each part of the frame at different speed levels and verify the large damage of the measuring point was mainly caused by resonance or forced vibration caused by high-frequency excitation based on early test conclusion.There are 97 figures,24 tables and 75 references.