Electrokinetic motion of a submerged oil droplet near an air–water interface. (31st December 2018) - Wang, Chengfa
Highlights: There is a separation distance between an oil droplet and an air–water interface. A negatively charged interface moves in opposite direction of the DC electric field. The effect of the mobile air–water interface on the droplet velocity was analyzed. This moving oil droplet surface and the inner flow affect the droplet velocity. Abstract: A numerical study on the electrokinetic motion of a charged oil droplet near a charged air–water interface is presented in this paper. First, the separation distance between the oil droplet and the air–water interface is calculated, and then the electrokinetic velocity of the droplet is simulated utilizing a three-dimensional numerical model under different applied electric fields, droplet's radii, ionic concentrations, zeta potentials of the oil–water interface, and zeta potentials of the air–water interface. The numerical results indicate that a negatively charged oil droplet near a negatively charged air–water interface moves in opposite direction of the direct current electric field and has larger velocity under higher electric field strength, droplet's radius, ionic concentration, and absolute values of the two interface zeta potentials.