Lattice Boltzmann method for electrowetting modeling and simulation

In this paper a free energy-based lattice Boltzmann (LB) approach for modeling and simulation of electrowetting is presented. First, based on the solution of the Poisson–Boltzmann (PB) equation, it is shown that the potential distribution inside a microsized droplet can always be assumed one-dimensional. Then, spreading and transporting of a microsized fluid droplet on a flat substrate, due to the electrowetting, are studied. By applying a voltage to the substrate, liquid–solid surface tension is locally decreased. To estimate the contact angle after applying the potential, new relations for surface tensions based on the free energy functional Minimization are proposed. The results are compared to the analytical and experimental results reported in the literature. A good agreement is found.