Lattice-Boltzmann Simulations of Electrowetting Phenomena

Rodrigo Ledesma Aguilar, Elfego Ruiz Gutierrez

Research output: Contribution to journalArticlepeer-review

6 Citations (Scopus)
12 Downloads (Pure)

Abstract

When a voltage difference is applied between a conducting liquid and a conducting (solid) electrode, the liquid is observed to spread on the solid. This phenomenon, generally referred to as electrowetting, underpins a number of interfacial phenomena of interest in applications that range from droplet microfluidics to optics. Here, we present a lattice-Boltzmann method that can simulate the coupled hydrodynamics and electrostatics equations of motion of a two-phase fluid as a means to model the electrowetting phenomena. Our method has the advantage of modeling the electrostatic fields within the lattice-Boltzmann algorithm itself, eliminating the need for a hybrid method. We validate our method by reproducing the static equilibrium configuration of a droplet subject to an applied voltage and show that the apparent contact angle of the drop depends on the voltage following the Young-Lippmann equation up to contact angles of â‰50°. At higher voltages, we observe a saturation of the contact angle caused by the competition between electric and capillary stresses, similar to previous experimental observations. We also study the stability of a dielectric film trapped between a conducting fluid and a solid electrode and find a good agreement with analytical predictions based on lubrication theory. Finally, we investigate the film dynamics at long times and report observations of film breakup and entrapment similar to previously reported experimental results.

Original languageEnglish
Pages (from-to)4849–4859
Number of pages11
JournalLangmuir
Volume35
Issue number14
Early online date14 Mar 2019
DOIs
Publication statusPublished - 9 Apr 2019

Fingerprint

Dive into the research topics of 'Lattice-Boltzmann Simulations of Electrowetting Phenomena'. Together they form a unique fingerprint.

Cite this