The current research attempts to describe the association between the aerodynamic drag and flow structures induced by train running in time-averaged and time-dependant views. A ICE2 train model is used as the research object, with the flow field solved by Large Eddy Simulation (LES). The validation is carried out through comparison with existing research data, and grid independence study in terms of time-averaged and second-order statistics. Numerical results are firstly presented by description of the time-averaged near wake flow topology based on surface flow visualization. Then, the wake integration method is used both time-averaged and instantaneously to link the aerodynamic force with integrated flow quantities on different wake planes: from the time-averaged perspective, the contribution of different flow terms to total drag is presented and compared; from the instantaneous perspective, the overall wake variation tendency is linked to the fluctuating component of aerodynamic force, based on the wake convection velocity and downstream distance of wake planes. The dynamic features of flow quantities in different locations are presented, with cross-correlation method used to describe the correlation between fluctuating aerodynamic drag and wake motion. Approaches and findings presented in the current study could serve as fundamentals which support future study.

当前的研究试图以时间平均和时间相关的视图来描述由列车运行引起的气动阻力和流动结构之间的关联。以ICE2列车模型为研究对象，流场通过大涡模拟（LES）求解。验证是通过与现有研究数据的比较，以及时间平均和二阶统计方面的网格独立性研究来进行的。数值结果首先通过基于表面流可视化的时间平均近尾流拓扑描述来呈现。然后，采用时间平均和瞬时的尾流积分方法将气动力与不同尾流平面上的积分流量联系起来：从时间平均的角度来看，呈现并比较了不同流量项对总阻力的贡献；从瞬时角度来看，基于尾流对流速度和尾流平面下游距离，整体尾流变化趋势与气动力的波动分量有关。给出了不同位置流量的动态特征，并用互相关方法描述了脉动气动阻力与尾流运动之间的相关性。当前研究中提出的方法和发现可以作为支持未来研究的基础。给出了不同位置流量的动态特征，并用互相关方法描述了脉动气动阻力与尾流运动之间的相关性。当前研究中提出的方法和发现可以作为支持未来研究的基础。给出了不同位置流量的动态特征，并用互相关方法描述了脉动气动阻力与尾流运动之间的相关性。当前研究中提出的方法和发现可以作为支持未来研究的基础。