Experimental study on condensate droplets movements in Marangoni condensation of ethanol-water mixture vapors on a horizontal surface

In this paper, an experimental system for Marangoni condensation of ethanol-water mixture vapors on a horizontal surface was designed and set up. Marangoni condensation under different experimental conditions was carried out, and the droplets movements were observed and recorded by the high speed camera. The movement velocity was measured and analyzed under different experimental conditions. As the vapor-to-surface temperature difference decreased, the droplet movement velocity decreased and the movement direction changed from negative to positive axis gradually. As the ethanol vapor concentration and the vapor velocity increased, the droplet movement velocity decreased and the vapor-to-surface temperature difference corresponding to the zero movement velocity increased.