Visualization of entrainment and surface behavior of high speed air jet blowing out from a hole to stagnant water

Nago, Kohei*; Koizumi, Yasuo*; Uchibori, Akihiro ; Ohshima, Hiroyuki

The experiment on a two dimensional air jet in a thin vessel filled with water was carried out to investigate the behavior of the jet interface and liquid droplet entrainment. The air jet in the water was recorded with a high speed video camera. The recorded photos showed that the filament-like ears and wisps were pulled out from the wavy water surface and the droplets were entrained. Droplet diameters and entrainment rate were obtained from the recorded photos. As the air velocity increased, the number of droplets increased lineally and the smaller droplets increased. The correlation for the droplet diameter distribution developed for the annular dispersed two-phase flow in a pipe predicted well the present experimental results. The correlations for the gas jet in the liquid pool underestimated the experimental results.