基于空簧气动响应的高速列车交会动力学分析

空气弹簧的动态特性受其内部压力影响较大，为了更深入地分析动车组高速交会时的运行安全性，需要考虑空气弹簧在交会流场下的气动响应。将空气弹簧的气动流体力学模型与某型动车组的整车动力学模型相结合，以列车交会气动流场压力的时间历程作为空气弹簧与车体的外部激励，分析了动车组以不同车速交会时的动力学特性。研究结果表明，交会车速越高，空气弹簧的内压波动幅度越大；会车中车体的垂向平稳性优于横向平稳性；轮轨垂向力与轮重减载率受会车流场的影响较小，在会车时有较大的安全余量；当两车以450km／h车速交会时，空气弹簧内压波动可达30．78％，且轮轴横向力与脱轨系数会在车头鼻端通过观测点的瞬间超过安全限制，影响列车的运行安全性。

A Dynamic Analysis of High Speed Trains Passing Based on the Pneumatic Response of the Air Springs

As the dynamic characters of the air spring are influenced greatly by its internal pressure, in or- der to analyze more deeply the running safety of high speed trains passing, the pneumatic response of the air spring under the flowfield around the trains is taken into consideration. A pneumatic fluid mechanics model of the air spring and a vehicle dynamics model of a certain type of EMU are connected together and the pressure time history of the trains passing flowfield is taken as the external excitation for the air spring and the carbody to analyze the dynamics characters of EMU in the cases of different speeds. The results show that, the higher the passing speed, the greater the fluctuation of the air spring internal pressure; the vertical comfort is better than the horizontal comfort during passing; the wheel/rail vertical force and the rate of wheel load reduction are influ- enced less by the passing flowfield, which still have large safety margins during passing; in the case of 450km/ h, the fluctuation of the air spring internal pressure can reach 30.78%. What~ more, the axle lateral force and the derailment coefficient are beyond the safe limit by the servation point, which will affect the running safety. moment when the front nose of the train passes the ob-