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| Snow Flight Characteristic and Prevention Research on the High Speed Railway in Cold Region |
| JING Guoqing, DING Dong |
| (Beijing Jiaotong University, Beijing 100044, China) |
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Abstract Abstract：Research purposes： The problem of snow flight obsesses high speed railway in cold region, where train structure and ballast bed cross section are important factors. In the paper, the k-epsilon Realizable viscous model is adopted together with sliding mesh technique, and CRH3 train-ballast bed numerical model is used to investigate aerodynamic effects, which reveals the mechanism of snow flight and provides theoretical basis for optimizing ballast bed cross section and preventing snow flight. Research conclusions： (1) Train head, tail and bogie area result in large fluctuation of wind pressure and speed, where the probability of snow flight is high. (2) There is large wind pressure and speed in the center of ballast bed, and snow blocks are easy to move and splash; the value of wind pressure decreases from center to side, and snow blocks are prone to move and cumulate in crib. (3) The key aerodynamic factor of snow flight is train speed. The value and fluctuation of wind pressure become larger with train speed increasing. When the train speed is above 250 km/h and increased by 100 km/h, the peak value of wind pressure is double. (4) The wind pressure increases with shoulder height, whose height of the shoulder ballast is from 0 mm to 150 mm at train speed 350 km/h, and the peak value of negative pressure increases by 9.0%. With lateral resistance value reach requirements, the shoulder height should be reduced. (5) The research conclusions can provide basis and reference for prevention and control of snow flight.
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Received: 07 August 2017
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2017, Vol. 34 
