A 3D MCCI code, CORCAAB, has been developed to account for uncertainty factors in the long-term molten corium–concrete interaction including changes in the three-dimensional cavity contour, which affect the convective heat transfer of the molten debris and late ablation behaviors. In this work, a 3D concrete ablation front tracking algorithm was formulated using the piecewise linear interface calculation method. The ablation and crust growth rates are governed by the local heat transfer across the 1D boundary layer that consists of molten debris, crust, slag, and concrete. This combination of the 3D and 1D methods led to the energy mismatch that was shown to be small enough even under a significantly large change of the cavity contour shape; thus, the proposed algorithm is compatible with the energy conservation law of the entire MCCI code. In order to test the efficacy and restriction of the proposed ablation algorithm, a simple rectangular cavity connected with a double sump on the cavity floor was adopted. Ablation surface formations including saddle points with multiple curvatures were confirmed to be adequate. A moderate dependence on the cell size was observed in predicting the disappearance of the thin walls separating the two partitions.

已开发出3D MCCI代码CORCAAB，以解决长期熔化的Corre与混凝土相互作用的不确定性因素，包括三维空腔轮廓的变化，这会影响熔融碎屑的对流传热和后期的烧蚀行为。在这项工作中，使用分段线性界面计算方法制定了3D混凝土烧蚀前跟踪算法。消融和结壳的生长速率受一维边界层上的局部传热控制，该边界层由熔融碎屑，结壳，炉渣和混凝土组成。3D和1D方法的这种组合导致能量失配，即使在腔轮廓形状发生显着变化的情况下，能量失配也足够小。因此，所提出的算法与整个MCCI代码的能量守恒定律兼容。为了测试所提出的消融算法的有效性和局限性，采用了一个简单的矩形腔体，该矩形腔体在腔体底板上连接了一个双槽。包括多个曲率的鞍点的烧蚀表面形成被证实是足够的。在预测分隔两个分区的薄壁的消失中观察到对细胞大小的适度依赖。