底部结构对高速列车流场及气动优化规律的影响

为了得到底部结构对列车流场及气动阻力优化规律的影响,通过计算流体力学和正交试验设计分析的方法,研究真实复杂车体的底部流动和尾迹特征,得到了复杂车体气动阻力优化规律.结果表明,尾车鼻尖静压系数在底部结构影响下降低了0.06,尾车流动分离提前,两反对称尾涡核间横向距离增大,尾涡间夹角增大.头型概念设计时的拓扑简化车体模型可以作为真实复杂车体的气动阻力优化设计模型,但考虑底部结构使得头车参数优化的极差值减小、尾车参数的优化极差值增大.头车阻力优化重点为转向架周边结构,尾车阻力优化对流线型长度参数更加敏感.

Influences of Underbody Structures on Flow Field and Aerodynamic Optimization Laws of High Speed Train

In order to obtain the influence of underbody structures on flow field and aerodynamic drag optimization laws of high speed train, the computational fluid dynamic and the orthogonal experimental analysis methods were adopted to studied underbody flow field, wake and the optimization law in complex train model. The results indicated that the pressure coefficient drops 0.06 in nose region of the tail car, and bogies moved the flow separation of the tail car ahead. The distances and the angle between antisymmetric wake vortices cores increased. The simplified topology model in concept design was suitable for aerodynamic optimization in complex train model design. However underbody structures decreased the optimization range of the head car, and increased the parameter optimization range of the tail car. The drag reduction of the head car should focus on bogie sections, and drag reduction of the tail car was more sensitive to streamline length.