制动性能对重载列车纵向冲动影响仿真分析研究

Simulation and analysis of the influence of braking performance on the longitudinal impulse of heavy-load trains

对于必须经常制动的重载列车,空气制动系统不应该存在故障。在这些列车中,远离机车的车辆比其他车辆晚几秒制动。相邻车辆制动之间的时间延迟很大程度上取决于主制动管中压力波(制动信号)的传输速度,该速度大约比自由空气中的声速低10-25%。后部车辆的滞后制动意味着后车与前车相撞,在缓冲器和车钩上产生较大的压缩力。这些压缩力主要是纵向的,被认为是产生机车车辆和轨道结构维修大量费用以及列车安全运行恶化的原因。相邻车辆的制动时间延迟,以及列车的车内动态相互作用,通过改变动力装置(机车)沿列车的位置而有很大不同。本文利用仿真分析技术,研究紧急制动过程中制动性能的位置对列车纵向冲动的影响。结果表明,列车之间动态相互作用的方式以及列车纵向压缩力和拉伸力的大小发生了巨大变化.

The air brake system should not be out of order for heavy haul trains that must be braked frequently.In these trains,the rear cars brake seconds later than the front cars.The time delay between the braking of adjacent vehicles depends to a large extent on the transmission speed of the pressure wave(brake signal)in the main brake tube,which is approximately 10-25 per cent lower than the speed of sound in free air.Late braking at the rear of the train means that the rear car collides with the front car,creating a greater compression force on the buffers and couplings.These compression forces,which are mainly longitudinal,are believed to be responsible for the large cost of maintenance of locomotives and the lower and upper structures of the track,as well as the deterioration of the safe operation of trains.The braking time delay of adjacent cars and the dynamic interaction of the train inside the train vary greatly by changing the position of the power plant(locomotive)along the train.In this paper,the effect of braking performance position on train longitudinal impulse during emergency braking application is studied by means of simulation analysis technique.The results show that the mode of dynamic interaction between trains and the magnitude of longitudinal compression force and tension of trains have changed greatly.The freight train considered is the freight train currently used by China Railway.