抄録
Under forced convection and atmospheric pressure conditions, heat transfer characteristics were studied using the annulus channel of a heater rod with highly-wettable surface. Improvement of phase change heat transfer under boiling and condensation process requires that either heating liquid or cooling vapor can contact a heat transfer surface, while a vapor-layer or liquid film is formed repeatedly on the surface during boiling or condensation process respectively. As oxide semiconductor materials such as TiO2 are known to be highly wettable, we made TiO2 coated surface on a metal surface. The Leidenfrost temperature for the TiO2 coated surface was higher than without coating. The surface temperature for variable power input was measured with thermo-couples located on the heater rod surface under forced convection conditions of 600-1700 kg/m2s in mass flux. The results for the TiO2 coated heater showed higher heat flux where the forced convection vaporization and larger critical heat flux.
