列尾压强对列车纵向冲动影响研究
Research on the Influence of Train Pipe Tail Pressure on Train Longitudinal Impulse

重载列车是铁路货运发展方向，2020年发生的3起事故，使重载列车安全问题再一次引起人们的关注，重载列车所有事故都起源于较大的车钩力，缓解时车钩力又是重中之重。由于重载列车缓解充风时间的不同，再制动时列尾压强通常存在较大差异，对列车车钩力产生影响。为探究不同列尾压强下的列车制动后缓解产生的纵向冲动水平，使用列车空气制动与纵向动力学联合仿真系统，对2万t重载列车在不同列尾压强时制动并缓解的工况进行计算，并对该过程中产生的纵向冲动水平及其成因进行分析。结果表明：列尾压强较低的列车空气制动力较弱，制动同步性较差但缓解同步性较好，空气制动时会产生较大的压钩力，但缓解时产生的拉钩力大幅减小，列尾压强较高的列车反之。
Heavy haul train is the development direction of railway freight transportation. With three acci-dents in 2020, the safety of heavy haul trains has attracted people’s attention again. All accidents of heavy haul trains originate from large coupler force, and the coupler force is the top priority when releasing. Due to the different release air charging time of heavy haul trains, there is usually a large difference in the pressure of train tail during re-braking, which has an impact on the train coupler force. In order to investigate the longitudinal impulse caused by the brake and release of trains with different pressure of train tail, this paper uses the Train Air Brake and Longitudinal Dynamics Simulation System to predict the brake and release of 20,000 t heavy haul trains under different pressure of train tail, and analyzes the level and causes of the longitudinal impulse generated in the process. The results show that the air brake force of the train with a lower pressure of train tail is weaker, the braking synchronization is poor, but the releasing synchronization is better. The train with a lower pressure of train tail will produce a larger compressing coupler force during air braking, but the tensile coupler force during the release will be greatly reduced. The train with high pressure of train tail is on the contrary.