Simulation of turbulent electrocoalescence

Abstract The combination of an electric field and a moderate turbulent flow is a promising technique for enhancing the separation of water from oil. In this work, a numerical framework based on the Eulerian–Lagrangian approach is presented, where the turbulent dispersion and the inter-droplet hydrodynamic and electrical forces are carefully handled. Water-in-oil emulsions are studied in a channel flow with almost isotropic, decaying turbulence. The results obtained agree qualitatively with experimentally data reported in the literature. Our simulations show that the collision frequency is mainly controlled by the turbulence, but strong electric fields may increase the collision rate at low turbulence levels. It is also observed that turbulent electrocoalescence works equally well for all simulated volume fractions of water droplets.

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