ICONE23-1075 A NUMERICAL SIMULATION OF HYDRODYNAMIC BEHAVIOR OF MOLTEN JET IN FUEL COOLANT INTERACTION

Abstract

It is important to investigate the molten jet behavior in fuel coolant interaction (FCI) during reactor severe accidents, which affects the subsequent phenomena, such as vapor explosion in light water reactor (PWR) or the molten core coolability in fast breeder reactor (FBR). The focus of the present study is placed on the numerical simulation of hydrodynamic behavior of molten jet including the deformation and surface waves in nonboiling conditions in order to isolate the jet breakup phenomenon from the complex interactions caused by coolant boiling. A multi-phase code with the Volume of Fluid Method (VOF) is used. Experimental data (Iwasawa Y, et al., 2014) is used as a benchmark to examine the capability of current approach. In this paper, effect of inject velocity and inject diameter on jet breakup length and breakup time are quantitatively analyzed. Effect of solidification is also discussed.