Dispersion Phenomena of Gas Molecules Diffusing from a Gas Bubble into a Liquid

Abstract

The purpose of this study is to observe directly how the gas molecules diffusing from a gas bubble disperse in the liquid phase. The single bubble was formed at single nozzle and rising up through the column full of a quiescent liquid. The observation of dispersion phenomena around a bubble were mainly carried out in the region from the release point of the bubble to the point where the bubble velocity reaches the steady state. Some observation were also carried out in the steady state region.
When the dispersion of gas molecules were visualized by using the iodine-starch reaction the dispersion phenomena was continuously photographed with a camera which is designed to move with single bubble. Consequently, it was confirmed that the dispersion pattern of the gas molecules around the bubble can be classified by two dimensionless parameters, namely Reynolds number Re=d_eU_b/ν and the dimensionless time elapsed from the bubble release t*=tU_b/d_e.