The lormation and initial motion of distilled water droplets injected into a viscous oil were studied in the absence of an electrical field and under the influence of a high voltage (up to 10 kV) field. The droplets were formed at a stainless steel nozzle in a rectangular cell (38 X 10 X 10 cm) equipped with grounded parallel plate electrodes along two sides of the cell.As the voltage applied to the nozzle was increased, the formed droplets were reduced in size and showed repulsion and some upwards scattering; the droplet velocity near the nozzle was greatly increased by the field, with the droplets decelerating as they moved away from the nozzle.Droplet formation and motion with and without electric field have been compared with predictive models, showing qualitative agreement and partial quantitative agreement.La formation et le dkplacement initial de gouttelettes d'eau distillte injectte dans une huile visqueuse, sont Ctudiis en I'absence d'un champ Clectrique et sous I'influence d'une haute tension (jusqu'a 10 kV). Les gouttelettes se foment h I'orifice d'un tuyau en acier inoxydable dans une cellule rectangulaire (38 X lox 10 cm) t5quipCe d'klectrodes plates paralleles mises h la terre sur les deux cBtes de la cellule.Lorsque la tension imposee a I'orifice est augmentke, la taille des gouttelettes formkes diminuent et les goutelettes rnontrent une repulsion et une dispersion vers le haut: la vitesse des gouttes prks de I'orifice est fortement augnientke par le champ, la vitesse diminuant a mesure que les gouttes s'kloignent de I'orifice.La formation et le dkplacement des gouttelettes avec et sans champ Clectrique ont et6 comparks a des modkles predictifs et Ics resultats montrent un bon accord qualitatif et un accord quantitatif partiel.

Mass transfer of benzoic acid from drops dispersed into a continuous phase of mineral oil with high viscosity has been investigated both with and without an imposed non‐uniform d.c. electric field. Total mass transfer efficiency was significantly enhanced in the presence of the high voltage electric field. The results indicate that the application of the electric field to the drop formation process does not change the fundamental mass transfer mechanisms and the mass transfer during drop free fall can also be described by existing mass transfer models. The results also suggest that the high viscosity of the continuous phase inhibits the drops oscillation as well as circulation when the drop sizes become smaller under the applied high voltage electric field. Therefore the significant enhancement of mass transfer efficiency in the present work is mainly due to the increased specific interfacial area.

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