Analysis Of The Frictional Heating Of Wheel-Rail Based On ANSYS

With the development of high-speed and heavy haul of railway, flat and spalling are more and more serious in wheel tread and rail surface. The wheel-rail frictional heating which causes wear damage is a major factor in running. So the wheel-rail contact analysis of the temperature field and stress field is very meaningful. The finite element model of wheels sliding on the rails and rolling process are established by large-scale finite element software ANSYS. Establish contact using the contact element method in the wheel-rail contact area. In the model, heating conduction is considered in contact interval between wheel and rail and the thermal convection between free surface and the environment, assuming that all the friction work completely transforms into friction heat, and friction heat distributes averagely to the wheels and rails. Use direct coupling method to solve frictional heating between wheel and rail, the thesis studies transient temperature field, stress field and shear stress of the wheel-rail contact area, the contact stress distribution characteristics, and maximum temperature rise and stress change.In pure sliding conditions, the contacted surface is very easy to produce instantaneous high temperature.1) The material nonlinear effects can not be ignored; 2) The thermal effect of wheel-rail is very thin layer on the surface, the maximum temperature and stress result from contact with the surface after depending on the center line; 3) Wheel-rail surface temperature and the highest stress increase with increasing the load, the relative sliding velocity and the friction coefficient.In the rolling-sliding contact conditions, the calculation does not consider the material nonlinearity due to temperature rising smaller. The results show that:1) Contact temperature is not high when high-speed train wheels running in low creep rate. But it has a considerable thermal stress, made the maximum temperature rise produce away from the contact area due to the very short contact time; 2) As the role of alternating hot and cold load wheels are prone to damage in the rolling process; 3) Maximum shear stress produced in a very thin layer of the contact surface, the thin layer is easy to shear failure.4) With the increase of the axle load, the friction factor and the creep rate the friction thermal effects of wheel and rail is more obvious.This calculation will provide a theoretical reference for flat and spalling of the wheel and rail, and will be of great significance for revealing heat damage mechanism.