Study on the Influence of Safety Injection Rate on the Process of SBLOCA

After the nuclear accident of TMI-2, more and more researchers devote to the researches of SBLOCA. It is almost impossible for the large break LOCA depending on the probability of the accident during the reactor life cycle. But it is possible for SBLOCA, such as opening a relief valve for a long time. After reactor shutdown, reactor takes the form of directly safety injection, which has great effects on the flow and heat transfer of the reactor pressure vessel and it has influence on the process of the SBLOCA finally. In present work, an SBLOCA analytical model has been developed with RELAP5 code to analyze special design features at SBLOCA accident. The results are compared with the calculations from Westinghouse NOTRUMP code. This analytical model has also used to analyze the effects of different safety injection rate on the process of accident. The transient variation about some key parameters have been obtained. e.g. the temperature, pressure variations of core, void fraction of core. The results show that the rate of safety injection has significant influence on the process of SBLOCA and the characteristics about the heat transfer of pressure vessel. Different safety injection rates influence the nuclear reactor safety differently.