Investigation of small break LOCA with failure of the emergency core cooling system accident management in VVER-1000 reactor type

Abstract

In this study, the thermohydraulic condition of the power plant is estimated as a result of the Small Break Loss of Coolant Accident (SB-LOCA) for Bushehr Nuclear Power Plant (BNPP) and the effect of control measures in postponing severe events as well as increasing the time available to enter control measures has been investigated. Two scenarios including control measures with and without operator action have been considered, considering the progress of the accident and the lack of effective intervention of control measures, both scenarios lead to the melting of the reactor core. The critical times for entering additional measures and restoring systems has been obtained from the progress of the accident for two scenarios that is used to develop an accident management strategy. The thermohydraulic calculation in this article deals with the estimation of time of critical point for accident management measures at a different phase of SB-LOCA.