Response characteristics of PWR primary circuit under SBLOCAs considering steam bypass discharging  

作　　者：Shuai Yang Xiang-Bin Li Yu-Sheng Liu Jia-Ning Xu De-Chen Zhang 

机构地区：[1]School of Nuclear Science and Engineering,North China Electric Power University,Beijing 102206,China [2]Beijing Key Laboratory of Passive Safety Technology for Nuclear Energy,Beijing 102206,China [3]Nuclear and Radiation Safety Center,MEP,Beijing 100084,China

出　　处：《Nuclear Science and Techniques》2024年第6期189-201,共13页核技术（英文）

摘　　要：Small-break superposed station blackout(SBO)accidents are the basic design accidents of nuclear power plants.Under the condition of a small break in the cold leg,SBO further increases the severity of the accident,and the steam bypass discharg-ing system(GCT)in the second circuit can play an important role in guaranteeing core safety.To explore the influence of the GCT on the thermal-hydraulic characteristics of the primary circuit,RELAP5 software was used to establish a numerical model based on a typical pressurized water reactor nuclear power plant.Five different small breaks in the cold-leg super-posed SBO were selected,and the impact of the GCT operation on the transient response characteristics of the primary and secondary circuit systems was analyzed.The results show that the GCT plays an indispensable role in core heat removal during an accident;otherwise,core safety cannot be guaranteed.The GCT was used in conjunction with the primary safety injection system during the placement process.When the break diameter was greater than a certain critical value,the core cooling rate could not be guaranteed to be less than 100 K/h;however,the core remained in a safe state.

关 键 词：Steam bypass discharging Pressurized water reactor SBLOCA Numerical simulation 

分 类 号：TL421.1[核科学技术—核技术及应用]