Korean Chemical Engineering Research

The Korean Institute of Chemical Engineers (한국화학공학회)
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Coalescence of Two Oppositely Charged Droplets at Constant Electric Potential

  • Lee, Dong Woog (Energy and Environment Laboratory, Kepco Research Institute) ;
  • Kang, In Seok (Department of Chemical Engineering, Pohang University of Science and Technology)
  • Received : 2021.01.21
  • Accepted : 2021.03.03
  • Published : 2021.05.01
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Abstract

Electrocoalescence is an active technique in petroleum industry, formation of raindrop in cloud, and digital microfluidics. In the present work, electrocoalescence of two droplets under the constant electric potential in air was studied. Through this experiment, we found that the electrocoalescence process could be divided three phases; deformation, formation of liquid bridge, and merging. And the condition for formation of liquid bridge between two droplets was obtained. For the connection of experimental result in constant potential condition with general case in constant charge condition, relationship of charge and potential difference was deduced by numerical computation. In high electric potential case, flat interfaces after recoiling were observed. It was interpreted through a numerical simulation of electric field.

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References

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