ON SIMULATION OF WHEEL/RAIL WEAR IN METRO OPERATION

Wheel and rail wear is extremely intensive in metro operation due to the high frequency of the regular train passages on the rails and to the intensive acceleration and deceleration of metro cars. In this paper, the results of a computer based complex analysis concerning the wear propagation vs. covered distance in case of wheels, or vs. contact frequency in case of rails, respectively, will be dealt with. The forces and velocities characterising the metro train operation on specified metro lines are determined by using the real-time simulation program TRAINSIM. The simulation results appear in form of tractive/braking effort and velocity distributions for the straight and curved track sections of the considered metro railway line. Wheel and rail wear propagation is treated by using simulation program system ELDACW, which takes into account the lateral track irregularities, as well. The wear simulation results in worn wheel and rail profiles as a function of the duration of the operation process considered. Based on the latter simulations, a comparative analysis is carried out to select the advantageous metro vehicle parameters. The objective function of the intended maximisation is the mileage performance of metro trains. The action parameters of the analysis are the longitudinal and lateral axle-box guidance stiffnesses, as well as the initial wheel profiles. The study gives recommendations to achieve increase in mileage performance.