Evaporating sessile droplet pair: Insights into contact line motion, flow transitions and emergence of universal vaporisation pattern

Abstract

We have deciphered that the vaporization rate of a pair of sessile droplets placed in a close vicinity of each other not only gets suppressed but also approached a universal pattern in the long time asymptotic limit, irrespective of substrate hydrophobicity. In a short time, these droplets exhibit a series of naturally evolving characteristics such as alteration of evaporation modes, flow transitions, asymmetric deformation, and motion of the contact line. Such dynamics are uniquely determined by the degree of pinning. In addition, we show that the enhanced hydrophobicity does not always lead to lower evaporation rate in droplets.