The Fatigue Life Prediction Of A High Speed Train Chassis

It is very important to analyze the fatigue life of the chassis,because the chassis is the main support part of the train and it is subjected to the alternating load from all sides during the driving process,which may lead to fatigue failure of the chassis.This essay exhaustively analyzed domestic and international research results,which is about the fatigue life of the high-speed train.The finite element and dynamic simulation analysis method is used to analyze the fatigue life of the high-speed train chassis that is the study object in this paper.Main studies are as follows:Firstly,it is built in Solidworks that the three-dimensional model of the high-speed train chassis.The three-dimensional model that is simplified will be import to ANSYS / Workbench,in which the three-dimensional model need to be converted to the two-dimensional model,to establish the finite element model of the chassis.It is checked that the mesh quality of the finite element model of the chassis,and it is found the quality of the mesh meets the requirements of engineering calculation.Secondly,it is carried out that the static analysis of the chassis finite element model.The stress analysis is carried out on the typical static load conditions,which include that the train no working only stand there,it is full of passengers,it is running smoothly,it is started suddenly and emergency braking.According to EN12663 standard check the static strength of the train chassis,the dangerous parts can be found in the chassis.These dangerous parts are also the most prone to fatigue damage.Thirdly,modal analysis of high-speed train chassis is carried out in Workbench,the main frequency and vibration mode of each mode of the train chassis is obtained.Then,the completed vehicle modal neutral file is imported into ADAMS / Rail to generate the flexible vehicle body.The bogie system is connected to building the rigid-flexible coupling dynamic simulation system of the vehicle.The dynamics simulation is carried out on the railway sample line.The dynamic characteristics of the train are evaluated and the load history of the dangerous parts of the chassis is obtained.Fourthly,the load history obtained from the dynamic simulation is input to the ANSYS,and the dynamic stress of the dangerous part is obtained.The fatigue load spectrum is compiled by rain-flow counting method.The S-N curve of the material was used to calculate the fatigue of the high-speed train chassis in the fatigue-tool,and the fatigue life was predicted according to the analysis results.