Bubbly flow and gas–liquid mass transfer in square and circular microchannels for stress-free and rigid interfaces: dissolution model
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A model is proposed to describe the dissolution of a chain of spherical pure gas bubbles into a nonvolatile liquid, along square and circular microchannels. The gas–liquid interface is considered stress-free or rigid. This model enables predicting, in each considered case, the evolution along the microchannel of the bubble diameter, the bubble velocity, the separation distance between two successive bubbles, the liquid fraction, the pressure in both the liquid and the gas phases, the concentration of the dissolved gas in the liquid phase and the mass transfer coefficient between the bubble and the liquid phase. The influence on the gas dissolution of the interfacial boundary condition, the microchannel type, the operating conditions and the physicochemical properties of the liquid and gas is analyzed. Existing experimental data for a nearly square microchannel are convincingly reproduced using the model. The validity and the different applications of the model are also discussed.
KeywordsMicrofluidics Absorption Square microchannel Circular microchannel Bubbly flow Spherical bubbles
The authors thank Sam Dehaeck for the useful comment about the possible volatility of the liquid. D.M. and B.S. acknowledge the Fonds de la Recherche Scientifique (F.R.S.-F.N.R.S.) for their financial contribution. This research has been performed under the umbrella of the COST action MP1106 and also takes part in the Inter-university Attraction Pole Programme (IAP 7/38 MicroMAST) initiated by the Belgian Science Policy Office.
- Bruus H (2008) Theoretical microfluidics, vol 18. Oxford University Press, Oxford, pp 41–50, 75Google Scholar
- Clift R, Grace JR, Weber ME (1978) Bubbles, drops and particles. Academic Press, New YorkGoogle Scholar
- Haberman WL, Morton RK (1953) An experimental investigation of the drag and shape of air bubbles rising in various liquids. David Taylor Model Basin, Report 802Google Scholar
- Mikaelian D, Haut B, Scheid B (2015) Bubbly flow and gas–liquid mass transfer in square and circular microchannels for stress-free and rigid interfaces. CFD analysis. Microfluid Nanofluid. doi: 10.1007/s10404-015-1578-0