Abstract In this study, measurement of turbulence intensity, pressure drop and local velocity field in the sodium fast reactor (SFR) wire-wrapped 19-pin bundle have been conducted to compare with the Reynolds averaged Navier–Stokes equations (RANS)-based computational fluid dynamics (CFD) simulations. The refractive indices between test section and working fluid, anise oil, were matched for the flow visualization. The turbulence intensity measurement showed that the transition of flow regime occurs at around Re = 13,800 at the test section. Pressure drop results revealed that the low-Re model showed the superior agreement with the experimental results. The particle image velocimetry (PIV) measurement was performed at the Reynolds numbers from 15,000 to 17,000. The velocity fields measured in the edge and interior subchannels. From the comparisons, it was found that the CFD simulation showed good agreement with the PIV measurement on specific flow characteristics such as vortex structure, swirl flow, and velocity direction change.

中文翻译：

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使用 MIR-PIV-PLIF 的 SFR 绕线 19 针束几何结构的流动可视化以及与基于 RANS 的 CFD 分析的比较

摘要 在这项研究中，测量了钠快堆 (SFR) 绕线 19 针束中的湍流强度、压降和局部速度场，以与基于雷诺平均纳维 - 斯托克斯方程 (RANS) 的计算进行比较。流体动力学 (CFD) 模拟。测试部分和工作流体（茴香油）之间的折射率与流动可视化相匹配。湍流强度测量表明，流态的转变发生在测试段的 Re = 13,800 附近。压降结果表明低 Re 模型与实验结果非常吻合。粒子图像测速 (PIV) 测量在雷诺数为 15,000 至 17,000 时进行。在边缘和内部子通道中测量的速度场。从对比来看，