Shape oscillating bubbles: hydrodynamics and mass transfer - a review

Abstract

AbstractThe subject of bubble oscillations, the associated hydrodynamics and the effect of bubbles on mass transfer in gas–liquid contact equipment, is reviewed. The emphasis is on rising and shape oscillating bubbles (n>0 mode) with little or negligible apparent volume change, rather than on volume oscillations (n = 0 mode). Bubbles, as they move in liquid media, are subjected to forces that try to deform them as well as forces that try to keep them as individual entities, resulting in the fact that bubble contact area changes in time and so do the velocity profiles surrounding them. As a result, the concentration profiles are also affected, influencing the Sherwood number and the mass transfer rates from the gas phase to the liquid phase. The physical properties of the phases as well as bubble coalescence and breakup processes that occur within the equipment play an important role in defining the oscillation amplitude and decay. Thus, we summarise the main results and the theories behind bubble dynamics...