Calculations and Analysis of Molten Core-Concrete Interaction and Its Mitigation Measures under Severe Accidents

This paper describes the major mechanism and model of MEDICS code,introduces the calcu-lation methods of the molten core-concrete interaction under severe accidents with MEDICS code,and gives the calculation results of MCCI under severe accidents and its mitigation measures.The calculation results indicate that the top cooling is an effective mitigation measures to MCCI.It can obviously delay the melt-through time of containment base,and largely reduce the total H2 and non-condensible gases release.