The influence of charge on the coalescence of water drops in free fall

Abstract

The influence of charge on coalescence was determined in the laboratory for isolated pairs of 340 and 190μm water drops falling freely at terminal velocity. A single charge-independent critical impact angle of 43°±1° was observed that distinguished an inner collision cross section for coalescence from an outer annual cross section for noncoalescence. Collisions occurring for impact angles less than the critical value always resulted in coalescence regardless of charge. Collisions having impact angles greater than the critical value resulted in either bounce, temporary coalescence or coalescence depending on charge. A satellite drop was produced with temporary coalescence at the intermediate charges of this experiment. -from Authors