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| Vivek V. Buwa | |
| Multi-scale Simulations | |
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Microscopic bubbly flow |
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To understand the effect of bubble swarms on magnitude of interphase
coupling forces like drag and lift, we are working on experimental
characterization and Volume-of-Fluid (VOF) simulations of rise behaviour
of mono-dispersed and poly-dispersed bubbly flows in quiescent and
sheared liquids. Experiments were performed to understand bubble size,
shape, and liquid phase properties on the rise behaviour of
mono-dispersed bubble swarms and to quantify the swarm effect on drag
coefficients. VOF simulations were performed to understand the magnitude
of lift force acting on a single isolated bubble as well as swarms of
mono-dispersed and poly-dispersed bubbles. |
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| Typical experimental images of mono-dispersed bubbly flow in air-water system (a) dB ~ 1.5 mm; (αG = 0.03), (b) dB ~ 3.3 mm (αG = 0.09) & (c) dB ~ 4.75 mm (αG = 0.16) | Effect of gas volume fraction on drag coefficient |
| Simulations of rise of behavior of a swarm of mono-dispersed bubbles in a simple shear flow | |
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| Simulated instantaneous bubbles shape and vorticity distributions for six mono-dispersed bubbles (dB =8 mm) rising in water + glycerol system. |
Time averaged CL of the individual bubbles for dB
= 8 mm was found to be within -0.2 to -0.8 as compared to CL
of -2.4 for single bubble rise |
| Simulations of rise of behavior of a swarm of poly-dispersed bubbles in a simple shear flow | |
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| Instantaneous bubbles shape and vorticity distributions for six poly-dispersed bubbles in water + glycerol system | |
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Publications/conference presentations: |
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