Initial microfluidic dissolution regime of CO2bubbles in viscous oils

Abstract

We examine the initial dynamical behavior of dissolving microbubbles composed of carbon dioxide gas in highly viscous silicone oils over a range of flow rates and pressure conditions. Microfluidic periodic trains of CO(2) bubbles are used to probe the interrelation between bubble dissolution and high-viscosity multiphase flows in microgeometries. We investigate bubble morphology from low to large capillary numbers and calculate the effective mass diffusion flux across the interface by tracking and monitoring individual bubbles during shrinkage. The initial flux is characterized using a dissolution coefficient that reveals the influence of the oil molecular weight on the dissolution process. Our findings show the possibility to control and exploit the interplay between capillary and mass transfer phenomena with highly viscous fluids in small-scale systems.

Lateral movements in Rayleigh–Taylor instabilities due to frontiers. Experimental study

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Viscous fingering and deformation of a miscible circular blob in a rectilinear displacement in porous media

“…This is the case for instance in localized pollution events in soils where underground flows may entrain either more or less viscous spills of finite spatial extent. Similarly, in CO 2 sequestration techniques, the CO 2 sample migrates as an irregular plume of finite extent within, for instance, water, oil or brine of different viscosity (Lagneau, Pipart & Catalette 2005;Sauzade & Cubaud 2013;Huppert & Neufeld 2014).…”

Calculating the volume of elongated bubbles and droplets in microchannels from a top view image

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