Numerical multiphase modeling of bubbly flows

摘要

Bubbly flows appear in a large variety of engineering applications from the petroleum to the nuclear industry. A common model used in these contexts is the so-called drift–flux model where the slip velocity (the difference between the velocities of the gas and of the liquid) is expressed on the basis of empirical correlations. However, depending on these empirical correlations, these models are not always hyperbolic and this induces severe mathematical and numerical difficulties. Using asymptotic analysis in the limit of large drag terms, we propose an Eulerian mixture model where the slip velocity is expressed under the form of a Darcy-like law. We study the mathematical properties of this model and describe a Godunov type scheme for its approximation. Some numerical relevant test-cases are presented.