Abstract: For the simulation analysis of vehicle lateral stability may better represent the uncommon significance of self-excited vibration, a novel analysis methodology of lateral stability is proposed based on wheel/rail match. On contrast with wheel/rail geometrical contact, the contour interaction of the free-wheelset contact process, including contact geometrics/mechanics, can give more precise matching results. For a tram vehicle, the figures of equivalent conicity vs critical velocity are shown by applying the linear analysis methodology of critical velocity. If the wheel/rail matching relation is rational, the linear critical velocity will be validated by the non-linear simulation. The non-linear influence of critical velocity mainly comes from the wheel/rail matching relation, when the stable limit cycle of wheelset swing is very small, the non-linear influence can not be omitted. Besides wheel/rail matching relation, this methodology further presents the sensitive effects of the three following parameters to critical velocity: wheelset mass, longitudinal and lateral stiffnesses of primary suspension, and lateral damping. The optimal schemes of the tram vehicle is presented, which will increase the speed of existing rails.

Key words: Critical velocity, Equivalent conicity, Lateral stability, Tram vehicle, Wheel-rail match