Description of the VOF based pressure algorithm and application to XT-ADS like spallation target

Abstract

The simulation of Heavy Liquid Metal Vacuum complex interfaces with Starccm+ from CD-Adapco using the Volume of Fluid (VOF) framework requires specifi c care. In a first part, we describe how we managed to deal with the high density ratio and the interface smearing in the context of three different windowless spallation targets. The interface smearing is controlled with a non-conservative condensation term. The second part is dedicated to the individuation of the relevant physical process leading to the interface sharpening and its inclusion in the set of constitutive equations. The methodology used has been to re-derive the VOF equations for momentum and phase transport from the constitutive phase equations. Two candidates for sharpening are individuated: baro-diffusion and surface tension effects. Only baro-diffusion is however likely to have the required strength in the foreseen applications.