Severe accident analysis and related nuclear data

Tsujimoto, Kazufumi 

The design of any nuclear power plant is impossible without safety evaluation. Analysis of design basis accident (DBA) considered to prove safety features of installed equipment to prevent accidents. On the other hand, analysis of severe accidents plays a very important role in risk assessments in order to reduce the probability of severe accidents with core melt to the level of 10 and less. In comparison to DBA, the main differences for the modeling of severe accident are connected fact that the object of modeling itself is not well defined due to changes of geometrical factors, composition of the melt and its properties. Evaluations related to nuclear data in the analysis of severe accidents are as following; (1) core composition and source term, (2) decay heat, and (3) criticality.