Research On The Influence Of Wheelset Flexibility On Dynamic Performance Of High-speed Train

In recent years,with the continuous improvement of train speed,the demands for vehicle dynamic performance are also constantly improving.The traditional multi-rigid vehicle model regards the vehicle parts as rigid bodies and ignores the elastic deformation of the parts of the vehicle system,which is not in line with the practical application to some extent.Hence,it is very necessary to consider vehicle components as flexibility in vehicle dynamics analysis.In this paper,based on rigid-flexible coupling dynamic theory of a domestic high-speed EMU wheelset,the rigid-flexible coupling vehicle model of flexible wheelset is processed and constructed by ABAQUS and SIMPACK with the modal substructure analysis method,and the dynamic indexes are compared with the multi-rigid vehicle model.In the first place,3d model of wheelset is established in SOLIDWORKS software,and then in ABAQUS software to the wheel to the meshing entity model,modal calculation,and generate the substructure to obtain the flexible body information of wheelset.Finally,the flexible information of the wheelset is imported through the FEMBS interface of SIMPACK software,and the rigid flexible coupling vehicle model of the flexible wheelset is established.In the second place,this paper describes the simulation of PSD track irregularity with SIMPACK in detail,and studies the influence of wheel pair vibration on vehicle dynamics performance under different line conditions and track irregularity excitation.The results show that: considering the wheelset flexibility,the vehicle model nonlinear critical speed decreases slightly,but it don’t fall much.When the vehicle runs in the straight line or the curve,the wheelset flexibility has some influence on the running stability of the straight line,but it is not obvious.When the vehicle passes through the curve,considering the wheelset flexibility,the wheel-rail vertical force increases significantly,the wheel-rail lateral force and lateral wheel rail force increase in a certain extent,and the wheel unloading rate increases slightly,while the derailment coefficient decreases slightly.Considering the wheelset flexibility,the wear index is higher than that of the rigid wheelset model at different speeds.Finally,in order to improve the modeling efficiency and reduce the calculation cost of the flexible wheelset vehicle model,this paper makes a comparative analysis of the results from the aspects of the selection of the main node and the coupling mode.The results show that the selection of the number and position of the master nodes,the substructure and the modal results of the full degree of freedom can meet the requirements of the analysis accuracy within the allowable error range.With the method of semi-coupling modeling,under the same working condition,there is little difference in the calculation results of safety and stability in curve operation between the two models of full coupling and semi-coupling.