傾斜上昇環状流における気液界面の性状  [in Japanese] Gas-Liquid Interfacial Characteristics in an Inclined Upward Annular Flow  [in Japanese]

This paper presents experimental data of the effects of pipe inclination on the circumferential variation of characteristics of annular liquid film and on the interfacial shear stress. In this experiment, film thickness was measured using the needle contact method and disturbance wave frequency and wave velocity were calculated from the output signals of time varying liquid film thickness by the constant current method. The inclination angles examined were 0°, 15°, 30°, 45°, 60° and 75° from the horizontal. Superficial velocities of air and water ranged from 20 m/s to 40 m/s and from 0.06 m/s and 0.20 m/s, respectively. The following results were obtained : i) The increase in pipe inclination makes the circumferential distribution of disturbance wave height uniform, while the wave velocity, frequency and length are not affected by the inclination. ii) A new correlation for the interfacial friction factor in an inclined upward pipe is obtained by modification of Fukano's correlation. iii) Simple charts were obtained to represent the relationship among interfacial shear stress, film thickness and flow rates of both phases.