Investigation of droplet dielectrophoresis movement under non-uniform AC electric fields

被引：0
|
作者：
Sun Z.-Q. [1 ]
Zhou Y.-T. [2 ]
Li N. [1 ]
Wang Z.-B. [1 ]
机构：
[1] College of New Energy, China University of Petroleum (East China), Qingdao
[2] School of Energy and Power Engineering, Xi'an Jiaotong University, Xi'an
来源：
Gao Xiao Hua Xue Gong Cheng Xue Bao/Journal of Chemical Engineering of Chinese Universities | 2021年 / 35卷 / 03期
关键词：
Dielectrophoresis; Electrocoalescence; Non-uniform electric field; Numerical simulation;
D O I：
10.3969/j.issn.1003-9015.2021.03.010
中图分类号：
学科分类号：
摘要：
Based on microscopic observation and numerical simulation, mechanism of droplet dielectrophoresis movement under non-uniform sinusoidal AC electric fields between honeycomb and suspended needle electrodes was studied. The results show that as voltage amplitude increases, dielectrophoretic force, velocity, droplet acceleration, fluctuation amplitude and frequency of instantaneous velocity all increase significantly. The average droplet velocity increased and then decreased with the increase of electric field frequency due to the influence of polarization and relaxation of droplet. The average velocity was the highest when the electric field frequency was 200 Hz. The resisting force increased with the increase of oil viscosity, and the transient migration velocity of droplet decreased to 1 mm∙s-1. With the increase of droplet diameter, the charge quantity of droplet increased, and the instantaneous velocity can reach as high as 3 mm∙s-1 when the droplet size was 2 mm. Droplet velocity fluctuated due to the change of electric field. Voltage amplitude and droplet size had significant effects on the fluctuation amplitude and frequency of instantaneous velocity, while electric field frequency and oil viscosity had few effects. These results can provide theoretical guidance for the design of efficient and compact electrocoalescer. © 2021, Editorial Board of "Journal of Chemical Engineering of Chinese Universities". All right reserved.
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页码：464 / 470
页数：6
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