静止水中を上昇する単一大気泡周囲液相流れ場への管内径の変化が及ぼす影響

抄録

The measuring method of the averaged liquid velocity fields around a large bubble rising in stagnant liquid in a vertical round pipe using Ultrasonic Velocity Profile monitor (UVP), which the authors have developed in the previous report, was applied to make clear the effect of pipe inner diameter, D, on the velocity field in this report. Two ultrasonic transducers inclined +20 degrees and -20 degrees from the horizontal line, respectively, were used for the measurement to get two dimensional velocity vectors. Three pipes of D = 32, 42 and 54mm were used in the measurement. According to the measured results, the velocity fields in the liquid phase above the large bubble, in the liquid film around the large bubble, and in the wake were presented and discussed, focusing especially on the effect of pipe inner diameter D.