An Integrity of Reactor Vessel Head and ICI Nozzle under In-Vessel Vapor Explosion Loads

摘要

An integrity assessment of lower head and ICI nozzle of the reactor vessel of Sinkori (SKR) #3/4 units under in-vessel vapor explosion loads has been performed. The core melt relocation parameters were chosen within the ranges of physically realizable boundaries. The premixing and explosion calculations were performed using TRACER-H code. Using the calculated explosion pressures imposed on the lower head inner wall and ICI nozzles, strain and stress were analyzed using ANSYS code. Then, the calculated strain results and the established failure criteria were used in determining the failure probability of the lower head and the ICI nozzles. Strain analyses showed that the failure of the lower head and the ICI nozzle due to the vapor explosion was not possible under the present framework of assessment.