Spreading of Droplets with Evaporation and Nucleation on Solid Surfaces

Abstract

An experimental investigation was conducted to visually observe the dynamical characteristics of water droplets with evaporation and nucleation on stainless steel and polished silicon surfaces. The water droplet diameter, contacting area and spreading speed were measured using a high-speed CCD camera at the surface temperature ranging from 110°C to 190°C. The spreading of water droplets under evaporation and nucleate boiling had a close relationship with the dynamic bubble behavior in the droplet as well as the surface properties. A model was proposed to describe the dynamical behavior of droplet spreading. Particularly, bubble volume, bubble interaction, surface temperature and surface properties had very strong influence on droplet spreading. Water droplets was easiest to spread at the surface temperature of 130 , and the spreading tendency increased with increasing surface coarseness. ℃