Hunting Stability Analysis of Tilting Railway Vehicles
摘要
Using the heuristic nonlinear creep model, this paper derives the governing differential equations of motion for a tilting railway vehicle moving on curved tracks. The tilting railway vehicle dynamics are modeled using a 31-degree-of-freedom (31-DOF) system, which takes account of the lateral displacement, vertical displacement, roll angle and yaw angle of each wheelset, the lateral displacement, vertical displacement, roll angle, pitch angle and yaw angle of the truck frames, and the car body. To analyze the respective effects of the major system parameters on the vehicle dynamics, the 31-DOF tilting system is reduced to a 24-DOF tilting model, by excluding designated subsets of the system parameters. The effects of radius of curved tracks on the critical hunting speed with respect to various tilting angles are illustrated. In addition, the effects of suspension parameters on the critical hunting speed with respect to various tilting angles are presented and compared. In general, the results obtained in this study show that with increase in tilting angle, the increments of critical hunting speed evaluated using the smaller superelevation angle are greater than those evaluated using the larger superelevation angle. Furthermore, the critical hunting speed derived using the tilting vehicle model is generally higher than that evaluated using the non-tilting vehicle model.