Ding Junjun

Longitudinal vibration of a resilient wheel under the adhesion limit

In order to study the longitudinal vibration law of a resilient wheel under the adhesion limit of different working conditions, two longitudinal vibration models of the resilient wheel of a motor vehicle are established, and the vibration laws and influencing factors of the resilient wheel under different operating conditions are studied by simulation. The model of the resilient wheel under low-speed driving and low adhesive operating conditions is established based on the Fastsim wheel/rail contact theory, and the other high-speed model of the resilient wheel is established by considering adhesion curve negative slope characteristics based on the Polach wheel/rail contact theory. The results show that at low-speed driving conditions, the longitudinal vibration of the resilient wheel is more violent than that of the solid wheel, and the sliding vibration of the resilient wheel at the adhesion limit is far greater than the nonadhesion limit at low-speed driving conditions. When the rail surface is polluted and the adhesion coefficient is low, with the speed increasing to 80 km/h, stick-slip vibration occurs on the resilient wheel due to the increased vibration between the wheel rim and the wheel hub. Under high-speed conditions, owing to the negative slope characteristic of the adhesion curve, the wheel adhesion recovery time decreases with the reduction of driving torque. The amplitude of vibration for the above two conditions increases with the increase in the stiffness of the motor boom and the longitudinal stiffness of the primary suspension. With the increase in the value of the radial stiffness and torsional stiffness of the resilient wheel, the vibration amplitude of the resilient wheel becomes smaller or suppressed. The vibration of the resilient wheel is transmitted to the frame through the primary suspension, which has little effect on the vibration of the vehicle body.