ABSTRACT In-vessel retention (IVR) is a strategy for severe accident management in which the lower head of the reactor vessel is submerged in a water-flooded reactor cavity. Critical heat flux (CHF) data for IVR are important for estimating cooling capacity of the reactor vessel. The existing CHF data for IVR which were obtained for the specific geometries and thermal-hydraulic conditions of actual plants are difficult to be applied to plants with other specifications. Hence, the purpose of this study is to develop CHF correlations applicable to various pressurized water reactor plants in a wide range of thermal outputs based on newly obtained CHF data. A rectangular test section with a cross-section of 150 mm × 150 mm and length of 600 mm was used for simulating a cooling channel. The thermal-hydraulic conditions expected in actual plants were studied, and the results were used in the experiment. The effects of parameters such as pressure, mass flux, thermodynamic quality, and angle on CHF were investigated . Based on these results, we developed a CHF correlation formula that can be applied to a wider range than previously, up to a maximum heat flux of 3000 kW/m2, and that predicts CHF with an error of ± 10%.

中文翻译：

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用于容器内滞留的临界热通量关联式的开发

摘要 容器内滞留 (IVR) 是一种严重事故管理策略，其中反应堆容器的下水头浸没在充满水的反应堆腔中。IVR 的临界热通量 (CHF) 数据对于估计反应堆容器的冷却能力很重要。现有的 IVR CHF 数据是针对实际工厂的特定几何形状和热工水力条件获得的，难以应用于具有其他规格的工厂。因此，本研究的目的是基于新获得的 CHF 数据，开发适用于各种压水反应堆工厂的各种热输出的 CHF 相关性。使用横截面为 150 mm × 150 mm、长度为 600 mm 的矩形测试截面来模拟冷却通道。研究了实际工厂中预期的热工水力条件，并将结果用于实验。研究了压力、质量通量、热力学性质和角度等参数对 CHF 的影响。基于这些结果，我们开发了一个 CHF 相关公式，该公式可以应用于比以前更广泛的范围，最大热通量可达 3000 kW/m2，并且预测 CHF 的误差为 ± 10%。