The study of meta-theory of nuclear safety in one single Initial Event

The purpose of this paper is to extend the meta-theory of theory of nuclear safety to a new stage. Meta-theory method describes nuclear power plant's nuclear safety systematically and is devised to analyze and to assist the investigation of the theory of nuclear safety. Different types of “capacity” and “load” via RISMC method were present by meta-theory, which could be found out from the real examples that one of load and capacity is deterministic, while the other is probabilistic. In the current research, the authors intend to develop all four combinations in one single Initial Event, aiming to extend this meta-theory method to a more extensive and practical level. A methodology has been verified by a specific yet simple engineering case, i.e., LOCA. To validate its logic, we present an Event Tree to explain the different responses of different safety systems. Then, RELAP 5 is programmed to establish a traditional LOCA sequence to investigate the changing situations of various parameters in reactor coolant system. Based on these approaches, the “capacity” and “load” should be described and all the four “capacity - load” cases in an Initial Event are determined.