Study On Dynamic Characteristics Of The ANTI-YAW Damper Used On Railway Vehicles

The anti-yaw damper is an important suspension component of the railway vehicle. To study the mechanical characteristics, especially the dynamic ones, is of great importance to increase the critical speed improve the dynamic performance of the vehicle, as well as the design of vehicle parameters.In this paper, on the basis of Maxwell linear equivalent parameter model and Kelvin-Voigt Model of hydraulic shock absorber, a nonlinear equivalent parameter model was developed by considering the piecewise damping characteristics caused by the damping valve opening characteristic of the anti-yaw damper. A dynamic test of one certain anti-yaw damper of the EMUs has been done on the shock absorber dynamic test bench. Comparing with the test results, the nonlinear model turned out to be able to more accurately reflect the dynamic characteristics of the anti-yaw damper, whether unloading or not.The dynamic characteristic curve of the anti-yaw damper and the influence of dynamic characteristics by the main parameters’change have been obtained, by analyzing the dynamic test and the nonlinear model of the anti-yaw damper. The dynamic damping and stiffness of both the damping type and the friction type anti-yaw damper had its own obvious frequency-dependent and amplitude-dependent property. The three important equivalent parameters in the nonlinear model of anti-yaw damper, such as unloading speed unloading force and equivalent series stiffness, had a significant impact on its dynamic characteristics, which showed some regularity.The matching relations between tread equivalent taper and two typical anti-yaw dampers has been discussed, through the simulation of railway vehicle multi-body dynamic model by SIMPACK and the analysis of actual vibration data measured from a certain intercity EMUs before and after replacing the anti-yaw damper. Small taper tread is adapted to match the friction type anti-yaw damper which works well in the low frequency condition to inhibit the first order hunting. And the large taper tread is adapted to match the damping type anti-yaw damper which works well in the high frequency condition to inhibit the second order hunting.