Modelling of Solidification Effect in Eulerian Fuel-Coolant Interaction Codes

Abstract

The solidification influence modeling in fuel-coolant interaction codes is strongly related to the modeling of the temperature profile inside the melt droplets and to the modeling of the mechanical effect of the formed crust on the fine fragmentation process. A purpose of the study was to enable solidification influence modeling in codes with an Eulerian formulation of the droplet field. Therefore additional transporte quantities based on the most important melt droplet features regarding the steam explosion phenomenon were derived. This enables a more accurate prediction of the amount of droplets participating in the fine fragmentation process during the explosion phase. Also the potential effect of the proposed modeling was assessed. The simulations supported the key role of the solidification in the steam explosion phenomenon.