Effects of dynamic contact angle on numerical modeling of electrowetting in parallel plate microchannels

Abstract

Electrowetting phenomenon in parallel plate microchannel is investigated numerically. The current study advances accuracy of numerical modeling of electrowetting by considering dynamic behavior of the tri-phase contact line using molecular-kinetic theory. This theory in conjunction with volume of fluid method, which has been proved to be a powerful approach for free surface modeling, is used to simulate the phenomenon. By comparing the results against experimental data from literature, the simulation demonstrates significant improvement in results. It is concluded that ignoring dynamic features of wetting leads to overestimation of the effect of electrowetting actuation on various parameters including contact angle, aspect ratio and velocity of the droplet.

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Acknowledgments

The authors would like to acknowledge SIMULENT Inc., Toronto, Ontario for making SIMULENT code accessible for this study. We thank four anonymous reviewers and Nima Maftoon for their many helpful comments. A. D. would like to thank the support of MDEIE and FQRNT.

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Correspondence to Lyes Kadem or Ali Dolatabadi.

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Keshavarz-Motamed, Z., Kadem, L. & Dolatabadi, A. Effects of dynamic contact angle on numerical modeling of electrowetting in parallel plate microchannels. Microfluid Nanofluid 8, 47 (2010). https://doi.org/10.1007/s10404-009-0460-3

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Keywords

  • Electrowetting
  • Molecular-kinetic theory
  • Dynamic contact angle
  • Contact line velocity