The Experimental Study of Evaporation of Water–Alcohol Solution Droplets

Abstract

Experimental data have been presented on the evaporation of water–alcohol solution droplets with different concentrations. The droplets have been suspended by a thread and applied onto a planar surface. The dynamics of variations in the geometric parameters of the evaporating water–alcohol solution droplets has been studied with the use of high-speed microphotography. Infrared thermography has been employed to confirm the three-stage variation in the surface temperature of the evaporating droplets, namely, an initial dramatic decrease in the temperature, the stage of a constant temperature, and its smooth increase up to the ambient air temperature. The experimental data have shown an essential influence of the solution concentration on the droplet evaporation process. The higher the ethanol concentration in a droplet, the closer the character of variations in the surface temperature and geometric parameters of the droplet to the variations in the same parameters of an alcohol droplet.