Research On Influence Foctors Analysis Of3-D Wheel-rail Nonlinear Contact Based On ANSYS

With the continuous growth of train speed and load,the train driving environment isbecoming more and more severe. So it will put forward higher requirement of vehicle,trackstructure and etc design.The wheel/rail is an important part which contacts vehicles andfoundation, and the wheel/rail contact is the fundamental basis of train traction, but also forthe entire transport.Many disciplines are involved when study the wheel/railrelationship.Wheel/rail rolling contact theory is the basis for the research and the wheel/railcontact behavior is the key research content.With the complex geometries and the highnonlinear behaviors,the wheel/rail relationship has become one of the most complicatedproblems in the vehicle and track researches.Highly accurate solutions are not able to get byusing the traditional elastic mechanics calculation method.Similarly,because of the basicassumptions of Hertz contact theory,the complex problem of wheel/rail nonlinear contact isnot deeply studied.With the development of computer technology and finite elementtheory,three dimensional(3D) nonlinear wheel/rail contact study becomepossible.Furthermore,the3D model is established in accordance with the real geometries ofwheel and rail. Using the contact element to simulate highly nonlinear wheel/rail contactproblem.ANSYS,which is a large structure analysis software,provides a good platform for the3D nonlinear wheel/rail contact analysis.In this paper, the Hertz contact theory and the finite element method dealing withnonlinear contact problem are introduced.On this basis,the influence factors of the wheel/rail3D nonlinear static and dynamic contact are researched.And wheel/rail3D nonlinear contactfinite element model is established by making use of the ANSYS.The TB conical tread and60kg/m rail are adopted in modeling.The rail bottom slope is1:20.Accurate size shape and stress distribution of contact area are not gotten through thetraditional calculation methods including Hertz contact theory and elastic analysismethod.Due to the above reasons,The method of using the ANSYS to establish3D nonlinearwheel/rail contact calculation model for the analysis of influence factors is taken.Staticcontact analysis results show that the material plastic deformation should be considered whenstudy the3D nonlinear wheel/rail contact problem for the sake of the true contact behavior.Bychanging the wheel weight and foundation stiffness,the simulation results indicate the shapeand size of contact area change with the wheel load and the small foundation stiffness canreduce the wheel/rail contact stress.In the process of dynamic contact analysis,the whole largefinite element model of wheel/rail is established.The results show that a majority of the traindisplacement is due to the deformation of axle spring and the axle spring has played animportant role in weakening vibration.Reduce the foundation stiffness can better the wheel/rail vibration, but will increase the body vibration and reduce the riding comfort.At thesame time,the wheel/rail contact stress affected by train speed and foundation stiffness isanalyzed.Because of the influence of rail temperature,the different curvature radius raillocated high temperature and cold region are calculated by using the new finite elementmodel.The influence of temperature and different curvature radius on wheel/rail contact areanalyzed.