비등점의 가열 표면에서 나노유체 액적의 증발 특성

Abstract

This study aims to experimentally investigate the evaporation characteristics of nanofluid droplet on heated surface at boil- ing temperature of DI-water. In particular, textured surface was used to examine the effect of wettability on evaporation. At the initial stage of evaporation process, dynamic contact angle (DCA) of nanofluid droplet with 0.01 vol.% concentration on textured surface rapidly increased over its equilibrium contact angle by generated large bubble inside the droplet due to lower wettability. However, contact angle of nanofluid droplet with higher concentration on textured surface decreased with surface tension. In addition, total evaporation time of droplet on textured surface was considerably delayed due to reduction of con- tact area between droplet and solid surface. Thus, evaporation characteristics were highly affected by the nanofluid concen- tration and surface wettability.

This study aims to experimentally investigate the evaporation characteristics of nanofluid droplet on heated surface at boil- ing temperature of DI-water. In particular, textured surface was used to examine the effect of wettability on evaporation. At the initial stage of evaporation process, dynamic contact angle (DCA) of nanofluid droplet with 0.01 vol.% concentration on textured surface rapidly increased over its equilibrium contact angle by generated large bubble inside the droplet due to lower wettability. However, contact angle of nanofluid droplet with higher concentration on textured surface decreased with surface tension. In addition, total evaporation time of droplet on textured surface was considerably delayed due to reduction of con- tact area between droplet and solid surface. Thus, evaporation characteristics were highly affected by the nanofluid concen- tration and surface wettability.