Research On Dynamic Performance Of Articulated Emus Considering Traction

With the further research of rail transit technology and the rapid development of regional economy,intercity railway plays an important role in rail transit network because of its strengths of economic and comfort,safety and convenience,energy saving and environmental protection.At the same time,the proposal of the "One Belt and One Road" strategy has further driven the development of railway traffic construction in the Asia-Pacific region.With the vigorous development of international railway trade,in order to meet different operational needs,rail transit vehicles have been constantly updated and developed,structural forms have become more and more diversified in China.Articulated vehicles are widely used in high-speed trains,intercity trains,light rail trains and freight vehicles in foreign countries because of their low weight,good passive safety performance,excellent curve passing performance and mature foreign application technology.At present,there is little research on articulated vehicle with articulated power bogie in China.The influence of traction is not usually involved in the analysis of dynamic performance.Based on this,the study of dynamic performance of articulated EMU considering traction force is proposed.First of all,the characteristics and the research status of existing articulated vehicles and bogies at home and abroad are introduced in detail.Taking articulated vehicle with articulated power bogie as the research object,the overall of articulated EMU and structure scheme of articulated bogie are discussed.The dynamic model of4M1 T articulated intercity rail is established by SIMPACK.Based on this,the critical velocity,running stability,running quality and curve passing of articulated vehicle in idle running and traction condition are analyzed.The calculation results show that,when the articulated vehicle runs on a straight line,the stability index of car couplers is worse than the body ends,which is mainly because the articulated bogie makes the two adjacent car bodies hinged and have mutual influence.The variation trend of vehicle dynamic performance under traction condition is consistent with that under idle running condition,but there are differences.The dynamic performance indexes of articulated EMU under traction condition and idle running condition can all meet the relevant provisions of GB/T5599-2019.The effect of traction force on wheel-rail creep is analyzed and studied according to the difference of dynamic performance of articulated vehicle in traction and idle running condition.The results show that,the traction force makes the vehicle dynamic performance worse.Traction intensifies the fluctuation of wheel-rail creep rate and creep force,and changes the wheel-rail creep relationship of vehicles,thus indirectly affecting the vehicle dynamic performance.The longitudinal creep force of power bogie wheelset is significantly affected by traction force,so it is necessary to consider the influence of traction force in the calculation of vehicle dynamic performance.Finally,the influence of dynamic configuration on vehicle performance under traction condition was analyzed,and the study was carried out from the aspects of dynamic evaluation index,motion characteristics of articulated device,vehicle traction and adhesion performance.The results show that when the total traction power of the train is constant,the power dispersion mode reduces the influence of the traction force on the whole vehicle,and the increase of the ratio of the power bogie reduces the distribution of the traction force on the moving shaft and the wheel-rail adhesion coefficient at the starting stage.Among them,the dynamic performance and mechanical properties of the articulated device are better under 4M1T.