Frost layer growth behavior on ultra-low temperature surface with a superhydrophobic coating

Abstract

Experimental research was conducted to study the frost formation on superhydrophobic surfaces at ultra-low temperatures, which might broaden the insight into frost growth behavior on the heat exchangers. The frost properties were examined over time, and the frost retardation according to the frosting factor was identified using the frost reduction ratios. The ablimation-dominant (desublimation) mechanism was observed at ultra-low temperatures in which almost no water droplets were generated. Consequently, the influence of the superhydrophobic surface on frost retardation was insignificant within −5% owing to the frosting mechanism. It is difficult to expect an increase in thermal performance of heat exchangers by applying superhydrophobic surfaces; using superhydrophobic surfaces for the purpose of frost retardation at ultra-low temperatures is not recommended.