透明熱伝熱面を用いた高温壁面上の水の濡れの直接観測

抄録

In this experiment, single crystal sapphire and quartz glass are used for the heat transfer surface, and the liquid is cooled by a liquid jet with a two-dimensional temperature field fluctuation over time by a non-contact type temperature measurement using an infrared radiation thermometer and a high-speed video camera. We tried to measure the membrane behavior.In single crystal sapphire, the dependence of each liquid subcool degree on the MHF point temperature at the center of the superheated surface is qualitatively consistent with the value given by the Dhir-Purohit equation for each liquid flow velocity up to a liquid subcool degree of 20 K. In quartz glass, it was confirmed that the liquid subcooling degree of 40K has the strongest correlation with the Dhir-Purohit equation.The heat transfer coefficient of both single crystal sapphire and quartz glass improves as cooling progresses. At the same liquid flow rate at liquid subcool degrees of 10k, 20k, and 40k, the higher the liquid subcool degree, the better the heat transfer coefficient. At 10k, 20k, and 40k, the higher the liquid flow velocity, the better the heat transfer coefficient.The temperature at the tip of the liquid film when using quartz glass decreases as the liquid film progresses, and the liquid subcooling degrees 0K and 20K show close values. At 40K and 60K, the cooling water flow rate may affect the temperature at the tip of the liquid film.