Uncertainty Analysis of Molten Corium-Concrete Interaction during a Postulated Degraded Core Accidents for a Typical PWR

摘要

This paper illustrates the application of a severe accident analysis computer program to the uncertainty analysis of molten corium-concrete interaction (MCCI) phenomena in cases of severe accidents in nuclear power plants. The potential hazard of MCCI is the integrity of the containment building due to the possibility of a basemat melt-through, containment overpressurization by non-condensible gases, or oxidation of combustible gases. However, the MCCI has still large uncertainties in several phenomena such as melt spreading area, and/or heat transfer between the molten corium and overlying water pool (or basemat concrete). Therefore, an evaluation of the extent of the basemat melt-through, containment overpressurization by non-condensible gases, and oxidation of combustible gases was performed via uncertainty analysis using a MAAP computer program. The South Korean standardized nuclear power plant, OPR-1000, was used as a reference plant for the analysis.