青藏线棚车在强横风下的倾覆稳定性

Overturning stability of box-car on Qinghai—Tibet railway line with strong cross wind

采用缩比棚车模型风洞实验的方法研究棚车在5 m高路堤和15 m高桥梁上的气动性能,得到气动力系数与侧滑角之间的关系,在此基础上,根据静力矩平衡原理建立棚车整车在轨道上倾覆及车体在转向架上倾覆的数学模型,得到车辆在直线和曲线上运行时车辆运行车速和临界倾覆风速关系。研究结果表明:路堤或桥梁上棚车的气动力系数均随着侧滑角的增大而增大,在桥梁上侧滑角为75°时达到最大值,之后稍微降低;车体在转向架上倾覆时的临界风速小于车辆整车在轨道上倾覆的临界风速,车辆的安全速度限值应当以车体在转向架上倾覆为基础进行研究;车辆在曲线上静止时,其在路堤和桥梁上的临界倾覆风速分别为37.0和39.5 m/s,当车速为100 km/h时,其临界倾覆风接近30 m/s;若车辆在直线上静止时,其在路堤和桥梁上的临界倾覆风速分别为45.0和49.0 m/s,当车速为120 km/h时,在路堤或桥梁上棚车的临界倾覆风速接近33 m/s。

Scaled model and wind tunnel test were used to research on the aerodynamic performance of the box-car on 5 m high embankment and 15 m high bridge,and the relationship between the aerodynamic coefficients and the side sliding angle was gotten.Based on this,math models were built of the whole train overturning on the track and the car-body overturning on the bogie according to static moment balance,and the relationship between running speed and critical overturning wind speed was also gotten when they are running on straight and curve lines.The results show that the aerodynamic coefficients of the whole train increase with the increase of side sliding angle,and reach the maximum when the side sliding angle reaches 75° and decrease a little while on bridge.The critical wind speed of car-body overturning on bogie is less than that of train overturning on track,so train speed regulation should be based on car-body overturning on bogie.If train stays on a curve embankment or bridge,the critical wind speeds are 37.0 and 39.5 m/s separately,and if train speed is 100 km/h,the critical wind speed is near 30 m/s.If train stays on a straight embankment or bridge,the critical wind speeds are 45.0 and 49.0 m/s separately.If train speed is 120 km/h,the critical wind speed is near 33 m/s.