空气动力制动风翼在车上布置数值仿真研究

采用流体仿真分析软件FLUENT研究制动风翼尾迹的影响范围及制动风翼纵向间距对制动效果的影响,同时分析制动风翼不同横向间距对制动阻力影响的规律.结果表明:2幅制动风翼的纵向间距越大.列车前部制动风翼对后部制动风翼的尾迹影响越小,当2幅制动风翼的纵向间距超过2节车厢长度时,这种影响完全消失；在制动风翼面积相同的条件下,增大每幅2片制动风翼的横向间距,能够提高风翼的单位面积制动阻力;由制动风翼产生的制动瞬时减速度随制动初速度的增加而增加,在紧急制动初速度为500km>h-1时由制动风翼产生的制动合阻力约为160kN.此时的制动瞬时减速度约为0.33m.s-1,可知,列车高速运行时由空气动力制动产生的制动阻力对高速列车制动贡献很大,空气动力制动在高速时具有优良制动性能.

Numerical Simulation Research on the Arrangement of the Aerodynamic Braking Plates in the Train

Fluid simulation analysis software FLUENT was adopted to study the influence zone of the wake of the braking plate as well as the influence of its lengthwise distance on braking effect.Meanwhile,the influence law of its different lateral distance on braking resistance was analyzed.Results indicate that the lengthwise distance between two braking plates has a negative correlation with the effect of the wake of the front braking plate on the back one.As the lengthwise distance between two braking plates exceeds the length of two railway carriages,the effect completely diminishes.The increase of the lateral distance of two braking plates can increase the braking resistance per unit area provided that the areas of the plates are equal.The instantaneous deceleration caused by braking plate increases with the initial speed.The total braking resistance caused by braking plate is about 160 kN when the initial speed of emergency braking is 500 km·h-1,here the instantaneous deceleration is around 0.33 m·s-1.In conclusion,the braking resistance generated by aerodynamic braking contributes a great deal to the braking of high-speed train when train speed is very high,which proves that aerodynamic braking has excellent braking performance for high-speed train.