The method of corium cooling in a core catcher of a light-water nuclear reactor

Abstract

During the development of a severe accident at nuclear power plant with a core melting, corium is formed. One of the main barriers preventing outflow of corium into the environment is a melt localization device or a melt trap. The melt trap must accept and prevent the corium parameters from exceeding critical values, ensuring its retention in a controlled volume and cooling. For this reason, melt traps are subject to serious requirements regarding cooling methods to ensure effective containment of the melt in the core of a nuclear reactor. In the presented article, experimental studies of the interaction between corium and water, which was supplied to the surface of the corium in a melt trap for its cooling, were analyzed. As a result of the work, a number of significant problems associated with the low efficiency of this cooling method were identified, and possible ways to eliminate them were considered. A solution is proposed for optimizing the method of corium cooling in a melt trap, as well as for the scope of research on the possibility of implementing the proposed method in practice and analyzing its effectiveness using the VCG-135 test-bench and the Lava-B facility.