画像解析による環状噴霧流液滴の計測

抄録

In this study, measurements of droplet size and velocity in vertical upward annular-mist flow flowing up a vertical pipe with 10 mm-ID were performed using an image-processing based on a shadowgraph technique. Transient characteristics of droplet flux and velocity were also evaluated by means of the present technique. Total 9 datasets were obtained at the predetermined superficial liquid and gas velocities, ranging from 20 to 40 m/s for gas phase and from 0.1 to 0.4 m/s for liquid phase. The measured droplet size distribution varied greatly with change in gas flow rate, while its weak dependence on liquid flow rate at the fixed gas flow rate was confirmed. The measured droplet velocity profiles in pipe cross-section tended to obey the one-seventh-power law. Insignificant local slip velocity between gas phase and droplets was confirmed, while its average value tended to slightly increase with droplet size.