水平バンドル内気液二相流の正方および千鳥配列の違いによる流動への影響

抄録

It is important to investigate two-phase flow phenomena in tube bundles. In this study, difference of instantaneous and time-average void fractions in in-line and staggered tube bundles at pitch-to-diameter ratio of 1.5 were investigated. Void fraction distributions around tubes across horizontal tube bundle in liquid-gas two-phase flow were measured using X-ray radiography. It was confirmed that time-dependency of void fraction was more apparent in intermittent flow. Time-average void fraction distribution was high at front of a tube and low at back of a tube in bubbly and intermittent flows in the staggered bundles. Time-average void fraction at the maximum gap was higher than that around the other points at intermittent condition in in-line bundles. Volume-average void fraction in in-line tube bundle was approximately 20% higher than that in staggered bundle. Further, it was confirmed that volume-average void fraction at higher mass flux could be predicted by the Feenstra's equation.