Assessment of Two-Phase Flow Heat Transfer Correlations for Molten Core-Concrete Interaction Study

In case of a pressurized water reactor's severe accident with core meltdown and vessel failure, corium would spread on the concrete basemat of the plant. The high temperature of the corium pool maintained by the residual power would lead to the erosion of the concrete walls and potentially to the bypass of the containment. The ablation velocity of concrete is governed by the heat flux between the corium pool and the concrete wall, and its calculation is of particular significance to predict whether and when the basemat would fail in such a situation. From a hydrodynamic point of view, this issue is related to heat transfer between a volumetric heated bubbling pool and a porous wall with gas injection. Several experimental studies have been performed in the past, and many correlations have been proposed to address this issue. The main purpose of this paper is to assess these correlations from comparisons against the available experimental data. After a review of these data, the different correlations are presented. Attention focuses here on the correlations generally used in molten core-concrete interaction study: The Kutateladze-Malenkov, Konsetov, and BALI correlations. Deckwer's correlation is also included in this review. The comparisons between the results of these correlations and the experimental data are then discussed.