Analysis of interfacial forces on the physics of two-phase flow and hyperbolicity of the two-fluid model

The scope of this Master Thesis is the two-fluid model. This study aims at analysing their ill-posedness, showing how it is related to non-hyperbolicity and giving a measurement that I call the numerical hyperbolicity. As a cure to this important issue, we will propose a combination of physical and mathematical solutions. The physical forces that we will focus on are two interfacial forces: the interfacial pressure and the virtual mass. We will quantify the minimum correction that is necessary to ensure hyperbolicity of the two-fluid model. We will then compare the two forces and combine them into an aggregated correction. This correction is proposed for use as a criteria in the next generation of nuclear reactor thermal-hydraulics codes