多成分系の影響を考慮した燃料溶融挙動解析手法の開発

抄録

For improvement of Sever Accident (SA) codes, the core melting process has to be clarified because the numerical methods in SA codes for analyzing the core melting process are simplified. To clarify the core melting process quantitatively, it is necessary to understand the melting behavior of fuel elements which consist of fuel assemblies and control rods. Then we have been developing the numerical simulation method for fundamental melting behavior of fuel elements based on the POPCORN code. The POPCORN code was developed in Japan Atomic Energy Agency and is based on the Moving Particle Semi-implicit (MPS) method. In this paper, we introduced the numerical method for melting behavior in multi-component system including chemical reaction to the MPS method. In a melting process of fuel rod, some materials move in fuel rod and melting point changes. And chemical reactions including zirconium oxidation is also affect the melting behavior because of a heat generation. To consider these effects on melting behavior, we focus on oxidation movement in fuel rod and develop the numerical method for melting behavior in multi-component system based on diffusion of oxidation.