Dynamic performance of heavy-haul combined train applying emergency braking on straight line

摘要

A heavy-haul train-track coupled model is developed.Taking the emergency braking of the 2× 104 t combined train as example,the train longitudinal impulse,the coupler dynamic behaviors and wheel-rail interactions of vehicles distributing in the different positions are analyzed.The results indicate that under the coupler compressing forces,the couplers of middle locomotives may tilt to the free swing limits,which induces the unidirectional tilt of their connected wagon couplers.Consequently,the coupler longitudinal forces produce the lateral components,and then affect the wheel-rail dynamic interaction.The performance of the middle locomotive and their neighboring freight wagons deteriorate significantly,becoming the most dangerous parts in the combined train.The wagons disconnecting with the locomotives can basically keep their couplers to stabilize in the centering positions,even though the maximum coupler longitudinal force acts on it.And its corresponding running safety also has little changes.