Abstract In this work the capabilities of RELAP5-3D are tested against the experimental data gathered in the first experimental campaign on THALLIUM (Test HAmmer in Lead LIthiUM). THALLIUM, a LiPb facility, was built in 2015 at ENEA R.C. Brasimone with the aim to study the In-box LOCA by reproducing the LiPb loop of the HCLL TBS and the pipe forest at 1:1 scale. HCLL TBS (Helium Cooled Lithium-Lead Test Blanket System) was one of the Breeding Blanket concepts selected for ITER. The ITER classification system identified the In-box LOCA as a critical accidental transient for this type of TBS. For this reason, codes able to reproduce the consequences of this transient are needed to support the design of the LiPb loop. The simulations with RELAP5-3D used LBE (Lead-Bismuth Eutectic) as system fluid, as the thermophysical properties of LiPb are tabulated only up to a maximum value of 40 bar. The results of the simulations suggest that RELAP5-3D is able to reproduce the pressure wave propagation in the facility, with an average discrepancy of about 3.5 bar (i.e. an average percentage discrepancy of about 9.7 %), but also highlight two general discrepancies between computations and experiments.

中文翻译：

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使用 RELAP5-3D 对 HCLL TBS 的盒内 LOCA 瞬变的第一次实验活动进行数值模拟

摘要 在这项工作中，RELAP5-3D 的能力根据第一次 TALLIUM（铅锂测试锤）实验活动中收集的实验数据进行了测试。THALLIUM 是一个 LiPb 设施，于 2015 年在 ENEA RC Brasimone 建造，旨在通过以 1:1 的比例再现 HCLL TBS 的 LiPb 回路和管道森林来研究 In-box LOCA。HCLL TBS（氦冷锂铅测试毯系统）是为 ITER 选择的育种毯概念之一。ITER 分类系统将 In-box LOCA 确定为此类 TBS 的关键偶然瞬变。因此，需要能够重现这种瞬态后果的代码来支持 LiPb 回路的设计。RELAP5-3D 的模拟使用 LBE（铅铋共晶）作为系统流体，因为 LiPb 的热物理特性仅在最大值为 40 bar 时列出。模拟结果表明，RELAP5-3D 能够重现设施中的压力波传播，平均差异约为 3.5 bar（即平均百分比差异约为 9.7%），但也突出了计算之间的两个一般差异和实验。