Research on wheel wear and fatigue of urban rail trains under different traction characteristics

Abstract

Aiming at the problem that frequently train traction starting causes wheel wear and fatigue damage, on the basis of the constant traction force, the influence of the speed at the end of the constant power section of different traction characteristic curves on wheel wear and fatigue was studied. SIMPACK and MATLAB software were used for co-simulation to establish the dynamic model of urban rail trains(URTs) under different traction characteristics and the wheel wear model based on Archard. The influence of the speed at the end of the constant power section of the traction characteristic curve on the wheel-rail creepage, wheel wear depth, wear area and fatigue index of URTs under different starting torque of traction motor was analyzed. The results show that during the train traction starting process, the larger the starting torque of the motor, the greater the wheel-rail creepage, and the wheel wear depth and wear area, while the smaller the fatigue index; For agiven starting torque of the motor, with the increase of the speed at the end of the constant power section of the train traction characteristic curve, the wheel-rail creepage, and the wheel wear depth and wear area also increase, while the fatigue index decreases.When the starting torque of the motor increases from 800 N·m to 1 400 N·m, the maximum growth rates of wheel wear depth and wear area are 6.9% and 12.6%, respectively, while the maximum decline rate of fatigue index is 7.2%; When the speed at the end of the constant power section increases from 50 km/h to 80 km/h, the maximum growth rates of wheel wear depth and wear area are 4.4% and 4.3%,respectively, and the maximum decline rate of fatigue index is 1.9%.The effects of starting torque and the speed at the end of the constant power section on wheel wear and fatigue are obtained, which provides reference for the design of vehicle traction characteristics, motor control and wheel operation and maintenance.

Keywords

• vehicle engineering; urban rail trains; traction characteristics; wheel wear; fatigue index; wheel-rail creepage