A Phase-Field-Based Hybrid Lattice-Boltzmann Finite-Volume Method and Its Application to Simulate Droplet Motion under Electrowetting Control

Abstract

A phase-field-based numerical model combining the lattice-Boltzmann method (LBM) and the finite-volume method (FVM) is proposed and applied for the study of two-dimensional (2-D) droplet under electrowetting (EW) control by using alternating current (AC). The new model overcomes several limitations of the pure LBM in interface dynamics, while keeping the key advantages of LBM for hydrodynamics. The model formulation is presented and some numerical issues are discussed. Droplet motions under EW control are investigated by using this method, with the focus on the effects of key control parameters on the induced droplet oscillation. This study may provide useful guidelines for mixing enhancement within the droplet by EW control.

Keywords:

• Droplet oscillation
• electrowetting
• AC control
• phase-field model
• lattice-Boltzmann method
• finite-volume method