Research on the Simulation of the Motion Characteristics of Electrowetting-on-dielectric for Galinstan

In recent years, microfluidic technology has been widely applied in various fields. Electrowetting-on-dielectric (EWOD) technology, as one of the key techniques for droplet actuation, has broad application prospects in the electronics industry due to its excellent performance. This paper uses COMSOL Multiphysics® software to simulate the behavior of Galinstan droplets under EWOD, and investigates the droplet motion process. The simulation results show that the change in the droplet contact angle is caused by the slippage of the three-phase contact line. After applying a voltage, the three-phase contact line slides outward, altering the contact angle and inducing surface waves. After the surface waves attenuate, the droplet reaches a new stable state. Additionally, the paper simulates the electric field distribution of the system after EWOD stabilizes, confirming that the slippage of the contact line is a result of the electric field force acting on the three-phase contact line. The study provides theoretical support for understanding the motion mechanism of Galinstan in the EWOD process and for developing novel microscale devices based on this technology.