Influence of polygonal wheel on running safety of vehicle

Timoshenko beam and Euler beam were respectively used to simulate rail, linear induction motor (LIM) stator and reaction plate, concentration mass block and 3D entity finite element were respectively used to simulate ballast track and slab track, and vehicle/track coupling dynamics models with LIM were established.The influence of wheels with different wear degrees on wheel/rail normal contact forces and derailment coefficients on the two ballasts was analyzed.Calculation result shows that when vehicle passes the curved track with radius 300 m at 60 km·h^-1, the minimun and maximum wheel/rail normal contact forces on slab track are 55.34, 112.53 kN, and the maximum derailment coefficient is 0.290.The maximum and minimun wheel/rail normal contact forces on ballast track are 123.00, 60.70 kN, and the maximum derailment coefficient is 0.289.When vehicle passes the curved track with radius 600 m at 60 km·h^-1, the minimun and maximum wheel/rail normal contact forces on slab track are 52.93, 107.59 kN, and the maximum derailment coefficient is 0.064.The minimun and maximum wheel/rail normal contact forces on ballast track are 59.45, 112.33 kN, and the maximum derailment coefficient is 0.071.When vehicle passes the pits with wavelength 100 mm and three depths at 60 km·h^-1, the minimun and maximum wheel/rail normal contact forces on slab track are 49.54, 114.36 kN, and the maximum derailment coefficient is 0.024.The minimun and maximum wheel/rail normal contact forces on ballast track are 50.19, 134.29 kN, and the maximum derailment coefficient is 0.031.The derailment coefficients under various working conditions are never more than safety limit, and polygonal wheel can't cause vehicle derailment.