Abstract In thermal–hydraulic system codes, such as MARS and RELAP5/MOD3, the Savannah River Laboratory (SRL) model has been used as a subcooled boiling model for recent two decades. However, it has been known that the SRL model cannot properly capture the effects of liquid velocity and channel diameter on the development of axial void profile. The authors suggested the modifications of the SRL model in the previous studies, focusing on the net vapor generation model and the wall vapor generation model, and validated the modified model using 103 subcooled boiling experiments, of which pressures were limited up to 69 bar. In this work, the previous subcooled boiling model has been further improved for its extension to high-pressure conditions up to ∼ 150 bar using additional 42 sets of high-pressure experiments. The new model has been validated against a wide range of experiments. It was shown that the new model predicts axial void fractions better than the SRL model and the previous model for the whole pressure range and that it can completely replace the SRL model without any limitation.

中文翻译：

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热工水力系统代码过冷沸腾模型的改进

摘要 在热工水力系统代码中，如 MARS 和 RELAP5/MOD3，萨凡纳河实验室 (SRL) 模型已被用作最近二十年的过冷沸腾模型。然而，众所周知，SRL 模型不能正确捕捉液体速度和通道直径对轴向空隙剖面发展的影响。作者建议对先前研究中的 SRL 模型进行修改，重点关注净蒸汽生成模型和壁面蒸汽生成模型，并使用 103 次过冷沸腾实验验证了修改后的模型，其中压力限制为 69 bar。在这项工作中，使用额外的 42 组高压实验进一步改进了先前的过冷沸腾模型，将其扩展到高达 150 bar 的高压条件。新模型已经过广泛的实验验证。结果表明，新模型在整个压力范围内比 SRL 模型和以前的模型更好地预测轴向空隙率，并且它可以完全取代 SRL 模型而没有任何限制。