Abstract The falling thin water film on the vertical or inclined structure surface has been observed in various industrial fields. The water film behavior is also a key concern in nuclear safety, e.g. the PCCS water film cooling employed in advanced pressurized water reactors for containment heat removal and the process of washdown of aerosols deposited at the containment inner surface. The article briefly introduces the integrated falling liquid film model previously developed by the authors for the containment code COCOSYS and summarizes the current status of the model validation. Then the preliminary application of the model for aerosol washdown during accidents of nuclear power plants is performed and the possible approach involving the physical properties of aerosol particles for the washdown process is discussed. Afterwards, the integrated liquid film model is applied for the AP1000 PCCS film cooling with a refined COCOSYS containment model, for which the plume nodalization and the “Jet zones” are employed. The optimal strategy for the water film mass flow rate is discussed as well. The application and discussion of the integrated liquid film model in the field of nuclear safety also indicate that further theoretical and experimental studies ought to be carried out.

中文翻译：

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核安全评价安全壳规范中一体化降液膜模型研究

摘要 在各个工业领域都观察到垂直或倾斜结构表面上的薄水膜下降。水膜行为也是核安全中的一个关键问题，例如，先进压水反应堆中使用的 PCCS 水膜冷却用于安全壳热量的去除和沉积在安全壳内表面的气溶胶的冲洗过程。文章简要介绍了作者之前为遏制代码COCOSYS开发的一体化降液膜模型，并总结了模型验证的现状。然后进行了核电厂事故气溶胶冲刷模型的初步应用，并讨论了涉及气溶胶粒子物理特性的冲刷过程的可能方法。然后，集成的液膜模型应用于 AP1000 PCCS 薄膜冷却，采用精制的 COCOSYS 密闭模型，采用羽流节点化和“喷射区”。还讨论了水膜质量流量的最佳策略。综合液膜模型在核安全领域的应用和讨论也表明需要进一步开展理论和实验研究。