Experimental Studies of the Evaporation of Pure Liquid Droplets in a Single-Axis Non-Resonant Levitator

Though a simple daily observation, evaporation of drops is still poorly understood due to the complex nature that involves hydrodynamic effects in the bulk fluids and transport phenomena at the liquid-vapor interface. This paper reports on the evaporation of single component droplets (water, ethanol, acetone, and glycerol) levitated in a single-axis non-resonant levitator. It was observed that the acetone and ethanol evaporated faster than water, although the acetone is the most volatile. The estimated lifetime of acetone is less than ۵min, which is much shorter as compared to ۵۶min for ethanol or about ۹۰min for water droplets. On the other hand, glycerol showed no tendency to evaporate. With increasing the evaporation time, the ratio of large and small semi-axis decreases and tends to ۱ corresponding to changes in drops shape from oblate ellipsoid to a sphere. Based on the classical D۲-law, the surface regression rates have been estimated.

Keywords:

Evaporation , Surface regression , Pure liquid droplet , resonant levitator , Non