Abstract In this paper, transient numerical simulations of maglev trains of different marshalling lengths (2, 4, and 8-car group trains) were conducted in the open air and without wind. This was done by solving the three-dimensional incompressible Navier-Stokes equations using an SST K-ω double-equation IDDES turbulence model. The results were compared with the results of wind tunnel experiments to verify the feasibility of numerical simulation. The results show an increase in the marshalling lengths of the train affects the flow above and below the train. With the increase of the marshalling length, the position of the flow separation in the tail car is advanced. The turbulence generated by the average shear on the x, y-plane and the x, z-plane as a component of the turbulence of the wake region increases. The region that produces non-vorticial vorticity in the main vortex becomes narrow and moves towards tail car. The structural analysis of the wake indicates that the wake structure of the 8-car group train is quite different from the other two groups. Both the time-averaged slipstream and the gust analysis show that the maximum expected slipstream velocity at the track-side increases as the train marshalling length increases. At the platform height, the change in vertical position of the wake vortex structure of the 2, 4, and 8-car group trains caused the difference of the shear flow regions. This is why the maximum expected slipstream velocity generated by the 4-car group train at this position is largest. As the marshalling length of the train increases, the time-average drag and lift force coefficient of the tail car have a significant negative correlation.

中文翻译：

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编组长度对磁悬浮列车流动结构的影响

摘要 本文对不同编组长度的磁悬浮列车（2、4、8节编组列车）进行了露天无风瞬态数值模拟。这是通过使用 SST K-ω 双方程 IDDES 湍流模型求解三维不可压缩 Navier-Stokes 方程来完成的。将所得结果与风洞实验结果进行对比，验证数值模拟的可行性。结果表明，列车编组长度的增加会影响列车上方和下方的流量。随着编组长度的增加，尾车分流位置提前。在 x, y 平面和 x, z 平面上由平均剪切产生的湍流作为尾流区域湍流的组成部分增加。主涡中产生非涡旋涡的区域变窄，向尾车移动。尾流结构分析表明，8节车厢组列车尾流结构与其他两组有较大差异。时均滑流和阵风分析都表明，轨道侧的最大预期滑流速度随着列车编组长度的增加而增加。在站台高度，2、4、8车组列车尾涡结构垂直位置的变化引起了剪切流区域的差异。这就是为什么4车组列车在这个位置产生的最大预期滑流速度最大的原因。随着列车编组长度的增加，