Study On Wheel/Rail Contact Problem Of The High Power Locomotive

As a national critical infrastructure, the main artery of national economy and popular means of transport, the railway shoulder great responsibility and arduous task in building an innovative nation and achieving a sound and fast development of the economic and the social. The development tendency of the railway construction in the world today is serving high speed trains and carrying heavy load. With the development arise some problems of the wheel/rail performance, the requirement of the train traction for the adhesion of wheel/rail will become more and more strict, and wheel/rail wear, rolling contact fatigue, derailment and noise will become more and more serious. The solution to the problems will have direct effects on the railway development. To solve these problems should base on the theory of wheel/rail rolling contact. In this paper,the wheel-rail contact problem was calculated and analyzed in which the high-power locomotive was the object.The most representative wheel/rail rolling contact theory is Kalker complete theory and"CONTACT"procedure based on the complete theory. Because of the supposes on which the Kalker theory base, the exact solutions is unable to obtain when conformal contact resulting from wheel flange close to the rail happens. And the theory cannot accurately simulate the geometrical shape and boundary condition of wheel/rail system. Finite element method can effectively solve the above problem and has a broad application prospects in the study of the wheel/rail contact problem.At first, the normal contact of two cylinders is used as a modle, the convergence of finite element method and the influence of mesh size on accuracy of the finite element method are analyzed with the comparison of the FEM results and the Hertz analytical solution. On this basis, based on the finite element mesh of Lagrangian description and the basic criteria of plastic contact theory analysis, a large-scale elast-plastic finite element model of wheel/rail contact is established with the real geometry of High-power locomotives wheel and rail. The size of the smallest cell of the Wheel-rail contact area is less than 1mm,the calculation of FEM model is completed by Parallel computer. The problem of contact nonlinearity, geometric nonlinearity and material nonlinearity can be solved by the model.Base on this FEM model, the influence of wheel/rail contact of high-power locomotive within different lateral displacements,different axle loads, different contact angles, and different radius of curves is calculated and analyzed when there is no traction torque and the influence of wheel/rail contact of high-power locomotive within different traction torque and different coefficient of friction is calculated and analyzed when there is traction torque. Then the variational laws of the contact force and contact stress field with Parameters above are obtained, which offers theoretical basis for the resarch of localization of high-power locomotive wheelsets.