Numerical simulation of a novel non-uniform electric field design to enhance the electrocoalescence of droplets

摘要

The behavior of binary droplet collision, exposed to an external electric field is studied numerically. Based on a fundamental understanding of the role of the electric field in the coalescence of aqueous drops in an immiscible oil phase, it is possible to optimize the design and operation of these external stimulators. In this research, numerical modeling of electrocoalescence is implemented, using Computational Fluid Dynamics (CFD) methods. Level set method is used to evaluate water droplet evolution in an oil phase under a novel concentric semi-elliptic non-uniform electric field configuration. The observations show that the shape of applied non-uniform fields can remarkably alter the electrocoalescence performance in a nontrivial way, which is sensitive to the drop-medium system. In addition to the shape of the medium, some other parameters such as droplets initial distance, initial skew angle of the droplets, applied voltage amplitude and oil viscosity are analyzed in the present paper. Our results can be useful in designing an optimum electrode configuration, achieving an efficient electrocoalescence. (C) 2019 Elsevier Masson SAS. All rights reserved.