Study on the Mechanism of Wheelset Angular Velocity Changing on Curved Tracks

The change of wheelsets' rotation angular velocity on curved tracks introduces velocity estimation errors, leading to inaccuracies in train positioning for the moving block system utilized by communication-based train control.Therefore, elucidating the mechanism and characteristics of angular velocity changing is crucial for assessing the accuracy of train location estimation.In this study, experiments and multi-body dynamics simulations were conducted to observe angular velocity changes on curved tracks.The experimental results indicates the changes of angular velocity on curved tracks, with the rotation of the front axle of the bogie notably slower than that of the rear axle.Simulation results indicate that the observed physical phenomenon can be replicated, with the relative change in angular velocity differing based on wheel/rail friction coefficient conditions.The mechanism of this variation is discussed in terms of path length differences between wheels, changes in rolling radius, and longitudinal creepages.Consequently, it is concluded that the distinct characteristics of longitudinal creepage depending on conditions are the primary determinant of the differential angular velocity of wheelsets on curved tracks.