Observation of Condensation Phenomena on Thin Tubes for Steam

Abstract

The steam condensation on the thin tubes was investigated. It was expected that the surface tension instability of the condensate appeared under the case when the vapor condensed on the thin tubes. The wettable surface of the stainless steel tube was prepared by using the wetting coating agent of titanium oxide. The wavy shaped condensate film appeared for the tubes having the diameter of 0.5mm and 0.2mm, while the smooth surface of condensate was observed for 1.0mm in diameter. It was clarified that although the distance between the neighboring convexes coincided with the analysis of Rayleigh for relatively low heat flux, it increased with increasing heat flux.