Bubble Dynamics in a Horizontal Rectangular Pipe with Rough Wall

抄録

An experimental study on a bubbly two-phase flow has been performed in a horizontal rectangular pipe with rough wall. The bubbles glide under the upper wall, the size of which decreases with an increasing roughness of the wall. The bubble diameter and the bubble population density have been well correlated with F=X^1/3Re^-1K^-1/4, where X, Re and K are quality, Reynolds number and roughness factor respectively. The distorted shape of large bubbles by buoyant force has well agreed with analysis. The bubble velocity is proportional to and lower than the liquid velocity around a bubble. It depends on the size but does not directly depend on the wall roughness.