Small break LOCA analysis without emergency core cooling systems using the RELAP5/SCDAP code in VVER-1000 reactor

摘要

In this study, the loss of coolant accident analysis without emergency core cooling system on in-vessel core melt progression is evaluated under a severe accident scenario in Bushehr VVER-1000 reactor. Using the RELAP5/SCDAP mod3.4 computer code, a best estimate simulation event of a 25 mm break SBLOCA, without ECCs is conducted until the reactor pressure vessel failure. In the performed analysis some important parameters such as the amount of hydrogen production, debris bed height and failure of lower plenum due to creep rupture are considered which are not included in the reactor FSAR.