A numerical model is developed to study the transient behavior of a liquid jet leaving a capillary tube under an electrostatic field. The surface profile of the deforming jet is defined using the Volume-of-Fluid (VOF) scheme and the advection of the liquid free-surface is performed using Youngs’ algorithm. Surface tension force is treated as a body force acting on the free-surface using continuum surface force (CSF) method. To calculate the effect of the electric field on the shape of the free-surface, the electrostatic potential is solved first. Next, the surface density of the electric charge and the electric field intensity are computed, and then the electric force is calculated. Liquid is assumed to be a perfect conductor, thus the electric force only acts on the liquid free-surface and is treated similar to that of surface tension using the CSF method. The developed model is validated by a comparison between the calculated results and measurements for an electrowetting scenario for which experimental results are available in the literature.

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