Modeling of phase inversion phenomenon in two-phase pipe flows

Phase inversion in oil–water flow systems corresponds to the transitional boundary between oil-in-water dispersion and water-in-oil dispersion. In this study, the criterion of minimum of the system free energy is combined with a model for drop size in dense dispersions to predict the critical conditions for phase inversion. The model has been favorably compared with available data on the critical holdup for phase inversion. It also provides explanations of features of phase inversion phenomena in liquid–liquid pipe flows and in static mixers.