Torsion frequency response function of a train driving wheelset

Abstract

The driven wheelset is used in traction rail vehicles (locomotives, electric trains, trams, etc.) to support part of the weight of the vehicle and to drive and brake the vehicle. The wheelset consists of the axle on which two wheels and the drive gear are mounted. The torsion vibrations of the driven wheelset may be induced by the variation of the adhesion force at the level of the contact between the wheels and the track but may also result from electromechanical interactions between the electric traction motor and the motor axle. In this paper, a mechanical model of the driven wheelset consisting of a circular shaft free at both ends and three rigid discs representing the two wheels and the drive gear is considered. The modal analysis method is used to solve vibrational motion equations in steady state harmonic behavior. The frequency response function of the system and the impact of the positioning of the drive gear on the wheelset shall be highlighted. For the verification of the proposed mechanical model, the numerical results are compared with the results obtained by experimental determinations carried out on a laboratory stand.