Analysis Of The Influence Of Yaw Dampers’ Mounted Position And Parameters On The Locomotive Dynamic Performance

Yaw damper is an important componnent and its mounted position and parameters both have a significant influence on the hunting stability and ride comfort to the high speed locomotives. Based on the opinions above,this paper will systematically investigate the influence of the matching of the yaw dampers’mounted position and parameters on the dynamic performance of the locomotives with simulation software SIMPACK.First of all,the influence of the yaw dampers’lateral mounted ponsition on the locomotive dynamic performance was investigated.Simulation results show that increaseing the mounted position of the yaw dampers in the lateral direction could improve the critical hunting speed obviously and the lateral riding comfort index to some extend.But this has little influence on the vertical riding comfort index when running on straight tracks and the derailment factor,wheel unloading ratio and the lateral wheelset-rail forces when running on the small-radius curved tracks.Increasing the lateral mounting position of the yaw dampers will make the yaw dampers more sensitive to the yaw motion between the carbody and the bogies so the hunting motion of the high-speed locomotive will be more effectively restrained.However, increasing the lateral mounted position of the yaw dampes may cause the locomotive exceeding the delimitation at the bottom.Based on the investigations and trouble above, in order to solve this issue this paper removed all the lateral dampers and mounted the yaw dampers on the end beams of the frame.The yaw dampers can function as yaw dampers and lateral dampers at the same time after parameters optimized which not only improved the dynamic performance of the locomotive further but also simplified the structure of bogies.This paper systematically investigated the influence of serise stiffness,unloading velocity,unloading force and cutting frequency of the yaw dampers when mounted on the end beams on the dynamic performance of the locomotives.Simulation results show that the series stiffness when the unloading force was choosed has a singnificant influence on critical speed of the locomotive,but the extent of the influence is affected by the unloading velocity;The unloading velocity and force also has a significant influence on the critical speed of the locomotive;The critical speed of the locomotive will be in direct proportion to the damping coefficient when the values of the unloading velocity are big and remain unchanged when the values are small.The trend of the critical speed varied with the variation of the parameters of the yaw dampers is determined by the cutting frequency and the damping coefficient.The cutting frequency determines the trend and the damping coefficient determines the maximum valve of the critical speed that the locomotive can achieve.After the unloading force was choosed,the lateral riding comfot index will be deteriorated with the decreasing of the unloading velocity which will be further deteriorated when increasing the series stiffness.The vertical riding comfort index was little influenced when changing the parameters of the yaw dampers.After the unloading force was choosed,changing the unloading velocity and the series stiffness has little influence on the derailment factor,wheel unloading ratio and the lateral wheelset-rail force when running on the small-radius curved tracks.After the series stiffness was choosed,increasing the unloading force will improve the derailment factor, wheel unloading ratio and the lateral wheelset-rail force when running on the small-radius curved tracks to some extent at first but will deteriorate the indexs soon after the improvement.