Flexible Wheelset-rail Spatially Coupling Dynamic Model Under Nonlinear Coupling Contact Model

With the rapid development of railway transportation, the running speed of vehicle become more and more higher and the interaction of wheel and rail become serious, which induces the different damage of some key components. Rigid wheel-rail spatially coupling dynamic model is always regarded as the main method to study the system of wheel-rail, but it is limited to study low frequency dynamic model and it isn't accurate to deal with high frequency dynamic model. The dynamic model considering the flexibility of wheelset can be suitable for this phenomenon, so it becomes a key domain for researcher from home and overseas. This thesis established flexible wheelset-rail spatially coupling dynamic model, which consider some factors including the multi-freedom coupling contact model of double row tapered rolling bearing, the flexibility of wheelset and wheel-rail spatially contact. The main work is listed as follows:Firstly, based on concentrated mass method and mode superposition method, this thesis established flexible wheelset-rail spatially coupling dynamic model dynamic model considering rail, adapter, the outer ring of the bearing, which include the nonlinear force of the bearing calculated by the multi-freedom coupling contact model.Secondly, the flexibility of the shaft is indicated by finite element based on Matlab. The property of elements is studied by spatial beam element. The element matrixs are obtained by equivalent stiffness matrix and consistent mass matrix. The whole mass matrix, stiffness matrix and load matrix are obtained by using space vector location method.Thirdly, spatial wheel/rail contact relationship is confirmed considering the flexibility of wheelset and the vibration of rail system. The contact parameter of flexible wheelset-rail system is revised, and wheel-rail contact point and correlated contact parameters are obtained by utilizing trace line method and minimum distance method. Wheel/rail normal force is obtained by Hertz nonlinear contact theory and Creep force/torque is obtained by utilizing Shen-Hedrick-Elkins theory. The load of correlative element is equivalented.Fourthly, the reason and practical significance of track irregularity is introduced. Different kinds of track irregular model are analyzed and the solution for track irregularity is introduced.Finally, take a bogie as an example, research the system operation stability and bearing's vibration performance under track irregularity.