Preliminary study of system design and safety analysis methodology for supercritical carbon dioxide Brayton cycle direct-cooled reactor system

Due to advantage of compact component and simply layout, supercritical CO2 (s-CO2) Brayton cycle is considered as power conversion system for small modular reactors (SMRs). The safety performance of SMRs coupling with s-CO2 Brayton cycle, especially for s-CO2 Brayton cycle direct cooled reactor, is quite different from that of conventional reactor systems. Safety analysis is essential work before the system design of a newly proposed reactor system is finalized. In this paper, preliminary system design and safety analysis methodology is proposed for a direct cooled reactor system (SCFR-300). System characteristic is clarified through simulation and analysis. Conceptual design of overall plant system is developed based on its unique characteristics. 35 initial accident events are obtained through main logic diagram. The system design and protection logic, and safety analysis methodology determined in this study will be used in further safety analysis. This work will provide helpful implications for safety performance evaluation for s-CO2 direct cooled reactor systems. (C) 2020 Elsevier Ltd. All rights reserved.