2020 Volume 5 Pages 63-68
A detailed experimental investigation was made on the droplet evaporation of an azeotropic mixture, ethanol solution of 1-heptane. The solution was a pressure-maximum azeotropic mixture and had a minimum boiling point in the azeotropic composition. The mixture droplet of 10 mm3 volume was slowly dripped on to heated brass surface, which was smoothly burnished and thinly gold plated to prevent oxidization. The evaporating behavior and the lifetime of the droplets were examined within a temperature range of the wall from 100 to 300℃. The results were compared with those of a non- azeotropic mixture, ethanol solution of 1-butanol. There were clear differences on the variations of Leidenfrost point and the variations of droplet-lifetime at Leidenfrost point with an increase in the concentration of the mixture, although the evaporating behavior of the azeotropic mixture droplets did not differ much from that of the non-azeotropic mixture droplets.
