BUBBLE SIZE EFFECT ON PHASE DISTRIBUTION

The effect of bubble size on phase distribution in vertically upward two-phase flow in a round tube is discussed based on measurement and visual observations. It turned out that, for fixed values of j_l and j_g, the phase distribution was drastically changed even with a small change of bubble-size distribution. The two-phase flow pattern transition was also affected very much by the bubble-size distribution. A formula was proposed to derive bubble-size distribution from the probability density function for bubble chord length, which takes into account the effect of multi-directional bubble movement.