列车大提速后周围流场变化诱发的事故隐患分析

选用CRH2型动车组l:l模型,对不同时速条件下列车周围流场进行模拟计算,得到列车所受空气动力随车速的变化规律,分析可能存在的安全问题.模拟结果表明:列车侧向力、升力和倾覆力矩均随着时速的增加而增大；列车快速行驶时,两侧处于负压状态,随着时速的增加负压程度也增强,垂直于列车方向压强梯度不断增大,轨道沿线两侧的行人或其它物体被卷入的可能性增加；与单列车模拟结果进行比较分析可以看出:两车交会时中间的压力非常低,列车的倾覆力矩明显增大,车体对内侧轨道的作用力也随之增大,列车运行危险性增加.

Analysis on security hidden troubles induced by variability of flow field due to raising train speed greatly

This paper used 1：1 model of EMU with its type GRH2,simulate and calculate the flow field around the train at under different speed conditions,got change rules of the train aerodynamic force with the speed and analyzed the potential safety problems.The simulation results showed that the side-force,lift-force and capsizing moment of the train increased with the increase of the speed;when the train was driving its two sides was in negative pressure,the negative pressure level increased with the increase of the speed,pressure gradient perpendicular to the train direction increased gradually and the pedestrians or other objects both sides of the train rail got involved more probably;.Compared with simulation results of a train,we could know that the intermediate pressure was very low when two trains met,the train capsizing moment increased sharply,the applied force which the train bodies acted on the inner side rail also increased and the driving risk of the train increased.