Directional motion of dielectric droplets on polymer-coated conductor driven by electric corona discharge

Abstract

Achieving better control of liquid droplet movement is an important subject for academic research and industrial applications. In this study, we investigate the use of electric corona discharge to drive and control oil droplet movement. For a fully covered polymer-coated copper plate, all droplets on the surface were found to move outward in the same direction. Interestingly, for a polymer coating a hole directly beneath a needle biased with a high DC voltage, we observed the existence of a zone boundary at which all of the droplets within the boundary move inward, whereas droplets outside the boundary move outward. The boundary appeared to depend on the hole size and the voltage bias. Our model simulations reasonably agree well with the experimental measurements of these peculiar phenomena.