Numerical Study of the Collision and Coalescence of Water Droplets in an Electric Field

The coalescence of binary water droplets in oil exposed to an external electric field is simulated using a model including both electrostatic and hydrodynamic sections. Available mathematical models for electric dipole-dipole force are presented in the first part of the model. Volume of Fluid approach is applied in the second part of the model. The simulation results were in good agreement with the published experimental observations. The results indicated that an improvement in electrocoalescence speed could be achieved. It was also revealed that the skew angle of the electric field, the oil viscosity, and the initial drops distance influence the electrocoalescence. Moreover, a correlation was developed to predict electrocoalescence kinetic as a function of the participant parameters.

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