Abstract The boundary layers that develop at the sides of full-scale operational inter-modal freight trains were measured using rakes of 4-hole dynamic-pressure probes. The average boundary-layer displacement thickness at the middle of the trains measured under low crosswind was 1.6 ​m (within the range of 0.5–3 ​m), showing turbulence intensities of 4– 13 % , and length scales of 5–30 ​m. These characteristics, together with other quantitative details provided in the paper, are intended to provide insight for future experiments and simulations to model real-world conditions around freight trains. The sensitivity of the boundary layer and flow topology to environmental crosswinds and loading configuration was also investigated. In addition, insight is provided into the unsteady flow topology around freight trains, the frequency content of the induced flow, and correlation characteristics.

中文翻译：

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全尺寸运营联运货运列车的边界层特征和非定常流拓扑

摘要 使用 4 孔动压探头的耙子测量了在全尺寸运行的多式联运货运列车侧面形成的边界层。低侧风下测得列车中部平均边界层位移厚度为1.6m（0.5-3m范围内），湍流强度为4-13%，长度尺度为5-30米。这些特征与论文中提供的其他定量细节一起，旨在为未来的实验和模拟提供见解，以模拟货运列车周围的真实世界条件。还研究了边界层和流动拓扑对环境侧风和负载配置的敏感性。此外，还提供了对货运列车周围非定常流动拓扑结构的洞察，