Integral Effect Test Coupling Reactor Coolant System (RCS) and Containment for Direct Vessel Injection (DVI) Line Break Loss-of-Coolant-Accident (IBLOCA)

A best-estimate evaluation for the safety of a reactor containment can be improved by a coupled analysis with a reactor coolant system (RCS), since major thermal hydraulic phenomena in the containment including a pressure and temperature (P/T) transient are highly dependent on the behavior of a mass and energy (M/E) supply from the RCS. In order to experimentally investigate the interaction between the RCS and the containment, an integral effect test facility, ATLASCUBE (Advance Thermal-hydraulic Test Loop for Accident Simulation Containment Utility for Bestestimate Evaluation) has been designed and constructed [1] at KAERI (Korea Atomic Energy Research Institute). In this study, a direct vessel injection (DVI) line intermediate-break loss-of-coolant accident (IBLOCA) was simulated by utilizing the ATLASCUBE facility, regarding that the IBLOCA scenario was of importance in a safety analysis according to a risk-informed regulation (RIR) [2]. Also, the characteristics of the M/E during the IBLOCA and the multi-dimensional effect in the containment according to the break simulation position were investigated with considering its impact on the P/T behavior.