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This paper presents the results of the International Benchmarking of Longitudinal Train Dynamics Simulators which involved participation of nine simulators (TABLDSS, UM, CRE-LTS, TDEAS, PoliTo, TsDyn, CARS, BODYSIM and VOCO) from six countries. Longitudinal train dynamics results and computing time of four simulation cases are presented and compared. The results show that all simulators had basic agreement in simulations of locomotive forces, resistance forces and track gradients. The major differences among different simulators lie in the draft gear models. TABLDSS, UM, CRE-LTS, TDEAS, TsDyn and CARS had general agreement in terms of the in-train forces; minor differences exist as reflections of draft gear model variations. In-train force oscillations were observed in VOCO due to the introduction of wheelâ\u80\u93rail contact. In-train force instabilities were sometimes observed in PoliTo and BODYSIM due to the velocity controlled transitional characteristics which could have generated unreasonable transitional stiffness. Regarding computing time per train operational second, the following list is in order of increasing computing speed: VOCO, TsDyn, PoliTO, CARS, BODYSIM, UM, TDEAS, CRE-LTS and TABLDSS (fastest); all simulators except VOCO, TsDyn and PoliTo achieved faster speeds than real-time simulations. Similarly, regarding computing time per integration step, the computing speeds in order are: CRE-LTS, VOCO, CARS, TsDyn, UM, TABLDSS and TDEAS (fastest)

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The wheel-rail rolling contact finite-element model based on arbitrary Lagrangian-Eulerian finite-element method (FEM) is developed and applied to the wheel-rail steady-state rolling contact analysis. Based on the wheel-rail steady-state rolling contact analysis, the wheel profile wear prediction methodology is developed and applied to wear of the wheel flange and rail gauge corner when the heavy-haul train passes on sharp curve track. The vehicle dynamic model is built in the ADAMS software, and the forces of the axle boxes acquired from the vehicle system dynamic model are loaded on the model of three-dimensional non-linear finite-element steady-state analysis for wheelset rolling contact process. Steady-state rolling contact analysis based on three-dimensional non-linear finite element is solved by the ABAQUS software. In the FEM simulation, a material model with bilinear kinematic hardening property is used. The wear modelling is based on the Archard's wear model. Laplacian smoothing with area weights is used to smooth the meshes of wheel and rail. Finally, the simulation results of a heavy-haul train wheel are analysed.