Exploring Flow Structures Around a Simplified ICE2 Train Subjected to A 30° Side Wind Using LES
Exploring Flow Structures Around a Simplified ICE2 Train Subjected to A 30° Side Wind Using LES
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DOI：
10.1080/19942060.2009.11015252
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发表时间：
2009-01
影响因子：
6.1
通讯作者：
H. Hemida;S. Krajnović
中科院分区：
文献类型：
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作者：
H. Hemida;S. Krajnović
摘要 采用大涡模拟 (LES) 来研究在 30° 偏航角的侧风条件下简化的 ICE2 列车周围的流动。基于列车高度和自由流速度的雷诺数为2×105。对具有不同节点数的两个不同网格进行两次计算，以检查网格分辨率对结果的影响。精细网格和粗网格给出相似的结果，这意味着结果与网格无关。结果还根据可用的实验数据进行了验证。 LES 结果与实验数据之间取得了良好的一致性。 LES 结果表明尾流中存在两种流态。第一个流态由尾流上部的稳定涡流线组成。从它们在列车表面开始的距离大约五个列车高度后，它会变成不稳定的脱落。第二种流态是尾涡下部的不稳定运动。它们以常规方式附着在火车表面或从火车表面分离。研究了 30° 偏航角下 ICE2 列车周围的时间平均流量和瞬时流量。
Abstract Large-eddy simulation (LES) is conducted to investigate the flow around a simplified ICE2 train under side wind conditions at 30° yaw angle. The Reynolds number based on the height of the train and the free stream velocity is 2×105. Two computations on two different meshes with different numbers of nodes are made to check the effect of the mesh resolution on the results. The fine and the coarse meshes give similar results meaning that the results are mesh independent. The results are also verified against available experimental data. Good agreement is obtained between the LES results and the experimental data. The LES results show that two flow regimes exist in the wake. The first flow regime consists of steady vortex lines in the upper part of the wake flow. It changes into unsteady shedding after a distance of about five train heights from their onset on the surface of the train. The second flow regime is the unsteady movement of the lower part of the wake vortices. They attach and detach from the surface of the train in a regular fashion. The time-averaged flow and the instantaneous flow around the ICE2 train at 30° yaw angle are explored.