Numerical Study of the Efficiency of Reflooding the Heated Core of a VVER-1000 Reactor at the Beginning of a Beyond Design Basis Accident with a Large Break LOCA

This article presents the results of a parametric study of reflooding efficiency performed using the example of a representative large break LOCA of a VVER-1000 reactor power unit. The study was performed using the SOCRAT/V3 code in relation to two parameters: the fuel rod cladding temperature at the coolant supply into the reactor downcomer and the coolant flow rate. The level of radiological consequences according to the INES scale is considered as an efficiency criterion. An analysis allowed for conclusions to be drawn about the efficiency of using reflooding as an accident management measure in accordance with the current level of knowledge.