横风工况下高速动车组空调表面气动性能数值分析

Aerodynamic Performance Numerical Analysis of Air-Condition in High-Speed EMU Under Cross-Wind

通过采用不可压缩粘性流体的N-S方程和k-ε双方程湍流模型,建立了高速动车组模型,对其在不同横风工况下运行的外流场进行了空气动力学仿真.分析动车组空调表面的压力分布规律,结果表明:列车空调机组所受阻力值由头车至尾车逐渐减小,横风等级增加,阻力值变化不大;空调机组进出口表面负压值及冷凝器进出口压差随横风等级的增加而增大,4、8、12级横风时,空调进出口表面负压总值较无横风时分别提高约30%、174%、561%;随横风等级增加,头车空调所受横向力并无显著变化,而中,尾车空调所受横向力急剧增加,且方向与头车所受横向力相反.4、8、12级横风时,三车空调及导流罩所受横向力总值分别为78、532、2 499 N.

Using N-S equation of uncompressible viscosity fluid and k-ε turbulence model,high-speed EMU model is constructed,a aerodynamic simulation is conducted on external flow under different cross-winds,and the distribution of pressure on the air-condition in the high-speed EMU is analyzed.The calculation results show that the resistance on the air-condition and the wind deflector reduces from head to tail.The resistance has changed little while increasing the level of the cross-wind;the negative pressure on the imports and exports of the air-condition and the pressure difference between the imports and exports of the condenser increase with the accretion of the cross-wind speed.When the level of the cross-wind is 4,8 and 12,the negative pressure on the imports and exports of the air-condition increases about 30%,174% and 561% comparing with the situation of none cross-wind.The increase in the cross-wind has little effects on the change of cross force on the head car,but rapidly increase on the rest cars.The direction of the cross-force on the head car is reverse with the other cars.When the level of cross-wind is 4,8 and 12,the total value of the cross-force is 78 N,532 N and 2 499 N respectively.