Natural Circulation Capability Assessment for Small-Medium Reactor

Small-medium reactors have been highly evaluated to have more safe characteristics than those of large reactors. In addition, it could be used for a variety of purposes, such as small-scale power production in mountainous or island area, seawater desalination, regional heating system, or large ships promotion power source. Various countries recently have substantiated the small-medium reactors . AST-500 (Russia), NHR-5 and NHR-200 (China), GHR (Germany), SMART (Korea). Since SMART (System-integrated Modular Advanced ReacTor) is integral type contrarily to the original reactors, it contains primary systems including a core, main coolant pumps, steam generators and a pressurizer within a reactor pressure vessel. Accordingly, it can exclude LBLOCA(Large Break Loss Of Coolant Accident) which is primary DBA(Design Basis Accident) of separated reactors. For a higher safety, we are designing a small sized reactor, REX-10(Regional Energy Reactor - 10 MWth), which uses a natural circulation system. In This study, to evaluate thermal-hydraulics of REX-10, we built experiment facility using the scaling law by Ishii