고화를 동반한 용융물 퍼짐 거동 예측에 관한 수치해석적 연구

다국어 초록 (Multilingual Abstract)

This paper presents the numerical investigations on the spreading behavior of UO₂-ZrO₂ based corium (VOLCANO VE- U7 benchmark) in the light water reactors and molten salts of FLiNaK and NaCl-KCl-UCl₃ in the molten salt reactors considering the melt solidification effect. The CFD analysis results of corium spreading with a wide phase change temperature of 1250 K showed good agreements with the experimental results of early phase spreading. Both Ramaccioti’s temperature-dependent viscosity model and the enthalpy-porosity method with the constant viscosity were found very effective to reflect the corium solidification. In addition, the decay heat effect could be considerable to enhance the melt spreading. However, some limitations were found in simulating the freezing at the leading edge both for corium and molten salts, which could play a barrier to prevent further spreading. More research is needed to simulate the thermohydraulic behavior of the eutectic melt materials such as molten salts.