Development of system analysis code and its application in transient simulation of supercritical CO2 Brayton cycle direct cooled reactors - Haijie Wu; Minyun Liu; Shenghui Liu; Jiatao Meng; Shuangqing Chen; Ruohan Zheng; Yanping Huang; Houjun Gong; Xiaoliang Zhu; TianYang Xing; Mudi Jiang (Annals of Nuclear Energy, 2025)