Influence of Different Wheel Coupling Mode to Wheelset Longitudinal Vibration

The longitudinal vibration models of traditional wheel-set, independently rotating wheel, elasto-damper coupled wheel-set are set up to research the longitudinal character. With the adopt parameter, both results of numerical analyses and theory analyses show that the wheel-set longitudinal vibration resonance speed is 58 km/h. There is violent longitudinal vibration resonance in the traditional wheel-set and elasto-damper coupled wheel-set when the speed is 58 km/h, but the independently rotating wheel is not occur the longitudinal vibration resonance phenomena. For the elasto-damper coupled wheel-set, when the torsion stiffness of the axle is big enough, the results is closely to the results of traditional wheel-set, and when the torsion stiffness of the axle is small enough the results is closely to independently rotating wheel. The difference in longitudinal vibration of the three wheel/rail coupled mode is caused by the coupled method of left/right wheels. The wheels of traditional wheel-set and elasto-damper coupled wheel-set is coupled by the axle rigidly or elastically, the difference rolling radius of the two wheels lead to the torsion vibration of the axle and induce the happen of wheel-set longitudinal vibration resonance. But for the independently rotating wheel, as the uncoupled function of the two wheels, the longitudinal creepage is nearly to 0, so it could not occurs longitudinal vibration resonance phenomena.