CFD modeling of water-in-crude oil emulsions

A CFD model has been developed that fits laminar data of both suspensions and stabilized water-in-oil emulsions using a relative viscosity model combined with a model for the stress of particles in a suspension. An analysis of rheology data for both suspensions and emulsions revealed that they share similar physics. We follow the approach that an emulsion can be treated as a suspension that does not reach maximum packing of particles, but rather undergoes a phase inversion at a critical dispersed volume fraction. By combining the rheology with a model of suspension stress in the context of Eulerian multiphase flow in a commercial CFD code STAR-CCM+, it has been possible to quantitatively model the pressure drop of salt water in crude oil emulsions during pipe flow with minimal fitting.