Heat transfer characteristics of micron ultrathin shear-driven water film flowing on a horizontal metal surface

The heat and mass transfer characteristics of shear-driven water film is widely investigated. Most reported studies are modeling work with series of assumptions. In this study, an experimental investigation on the heat transfer characteristics of shear-driven water film flowing on a metal surface was carried out. The surface is simplified as flat and horizontal, and the wind speed is fixed at 20.8 ~ 56.6 m/s. Variation of the width and surface temperature gradient of water film and the heat flux on solid-liquid and liquid-gas interfaces were quantitatively analyzed. As indicated, the width of the water film is dominated by the wind speed, at about 80 ~ 85 mm for a wind speed of 32.8 m/s. When the solid-liquid interface is under cooling and heating conditions at the temperature difference of 15 °C, their heat transfer densities are at ranges of -2 ~ 16 kW/m2, and 18 ~ 30 kW/m2, respectively. The collected experimental data could directly validate these existing and developing models in this field. Conclusions of this work also benefit for understanding the glaze ice formation mechanism and optimizing the anti-icing or de-icing system.