Electrowetting on dielectric and superhydrophobic surface: lattice Boltzmann study

Electrowetting (EW) effect is defined as changing in the interfacial energy of solid–liquid interface which causes to change in solid–liquid contact angle. In EW on dielectric (EWOD) actuations, the microliter drops are usually placed between two substrates which have some advantages. By modifying the voltages applied to the electrodes, it is possible to manipulate the droplets by setting up surface tension gradients along the plate. In this paper, the free energy based lattice Boltzmann method which has been recently extended by the authors for modeling and simulation of EW phenomenon has been applied to simulate EWOD. Also here we report the results of simulation of EW on superhydrophobic surfaces and pinning problem. The results have been compared with experimental data and show good accuracy of the numerical simulation.

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