Abstract We develop an analytical model about concrete ablation during ex-vessel cooling in a pre-flooded cavity. The model considers the melting of dry debris bed, the formation of crust, the growth of crust and the thermal ablation of concrete. This model can obtain concrete ablation depth during ex-vessel cooling. It is evaluated the adequacy of ex-vessel cooling in the pre-flooded reactor cavity of Westinghouse 3-loop nuclear power plants. If the debris bed is formed only in the zone directly below the reactor vessel narrowly and thickly, the characteristic of the debris bed should be like POMECO BED-5 and the pressure should be 2 bar or above to keep the integrity of the containment. However, if the debris bed is evenly distributed on the reactor cavity, it is assessed the pressure should be equal to or greater than 1 bar, 2 bar and 3 bar for POMECO BED-5, STYX BED and COOLOCED-8 BED, respectively.

中文翻译：

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预注西屋核电厂三回路核电站反应堆腔室出舱冷却过程中混凝土烧蚀的初步研究

摘要 我们开发了一个关于在预注水腔中的容器外冷却过程中混凝土烧蚀的分析模型。该模型考虑了干碎屑床的熔化、地壳的形成、地壳的生长和混凝土的热烧蚀。该模型可以在离船冷却过程中获得混凝土烧蚀深度。评价了西屋三回路核电站预充式反应堆腔内的船外冷却是否充分。如果碎片床只在反应堆容器正下方的区域形成又窄又厚，碎片床的特性应该像POMECO BED-5，压力应该在2巴或以上，以保持安全壳的完整性。但是，如果碎片床均匀分布在反应器腔体上，则评估压力应等于或大于 1 bar，