Study Of Wheelrail Geometrical Profile Optimization For High Speed Train

The wheel/rail interacting which is one of the fundamental techniques of high speed railways has been regarded as a main direction of progressive research in our country. For the existing wheel and rail profile, the space geometrical contact model has been set up respectively. And then, some research work for the wheel/rail profiles matching by means of numerical simulation under the high speed operating has been set out.In essence, the interacting between wheel and rail is a transmission of constraint forces. The wheel/rail space geometry contact state is one of the important factors for the mechanical process, and the wheel/rail geometry contact is a basis for calculating wheel/rail forces. The worn tread of wheel is more stable and better curve negociation performance. In general, the worn profile treads are all adopted on the modern rolling stock. As the typical worn profile treads of high-speed railway in our country, the HLM, LM, JM and GDM type treads are invested for the wheel/rail space dynamic contact geometry relationship in the program based on trace line method. Some analysis and comparisons of geometrical contact states between the different worn type treads and rails interactions are given. The abilities of motion stability, curve negociation performance and abrade of wheel/rail are discussed. The results show that there are great differences between the different wheel treads and rails interactions in the geometrical contact state. The HLM type tread has advantages of the motion stability and the critical speed in the straight line. The GDM type tread has a better curve negociation performance than others.Contact stresses are calculated for different sorts of wheel/rail profiles by means of numerical simulation. The results show that different profiles have different wheel/rail contact stresses, and the HLM and GDM type treads have lower contact stresses than others. So a better wheel/rail profile matching can reduce the contact stresses.Four improved profile schemes are put forward against different profiles' merits and demerits. The schemes B is chosen as the best design of the four schemes by means of analysing their contact geometry parameter, and it has lower contact stresses than the HLM, GDM type treads. In the end, the schemes B is recommended as our high speed train tread profile due to its perfect combination of stability and curve negociation performance.