Electrocapillarity motion of metal droplets

doi:10.7523/j.issn.2095-6134.2021.01.008

Abstract

Abstract: In this paper, the formula of electrocapillary motion was derived theoretically, and the electrocapillary motion of metal droplets in NaOH-starch mixture under the action of gravity was studied by a self-designed experimental apparatus.The electric field was applied in the above simulation system to film the motion track of the metal droplet and conduct image processing to obtain the instantaneous motion rule of the droplet. It is found that after applying electric field, the horizontal velocity component of the droplet goes through three stages:rapidly increasing to a maximum value, slowly decreasing to a stable value, and maintaining a stable velocity.The results show that when the mixture viscosity is between 853-1 760 mPa·s, the electric field intensity is between 90-135 V/m or the droplet radius is between 0.91-1.31 mm, the droplet velocity satisfies the formula of electrocapillary motion, that is, the electrocapillary velocity is proportional to the electric field intensity and droplet radius, and inversely proportional to the mixture viscosity.

Key words: interfacial tension, electrocapillary motion, image processing, two phase flow

CLC Number:

O647.6
O359

GUO Shengrong, LIU Runcong, DAI Xiaotian, WANG Xiaodong, NA Xianzhao. Electrocapillarity motion of metal droplets[J]. Journal of University of Chinese Academy of Sciences, 2021, 38(1): 54-61.

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