Corona Discharge-Induced Water Droplet Growth in Air

Abstract

In natural clouds, water droplets grow by condensation in a supersaturated environment. Under subsaturated conditions, water droplets normally keep evaporating until they eventually disappear. In this article, we study the effect of corona discharge on water droplet growth under both supersaturated and subsaturated conditions. It is shown that the formation of mist visible to the naked eyes could be induced by direct current (dc) corona discharge under supersaturated conditions. Furthermore, we find that corona discharge could promote the growth of water droplets even under subsaturated conditions. Possible mechanisms are discussed, and the results suggest that the droplet growth enhancement is supported by the synergetic effects of droplet surface charge, external electric field, and ionic wind generated by the corona discharge.