Bubble Train Flow

In this section we illustrate how the proposed theory for single, surfactant-laden bubbles in a cylindrical tube can be extended to predict the hydrodynamic resistance of bubble trains flowing in porous media. Some of the basic ideas are known (7, 23), so the present discussion is brief. 

Thulasidas TC, Abraham MA, Cerro RL. Axial dispersion of bubble-train flow in capillaries. Chem Eng Sci 1996. 

Using a simple scaling analysis, involving (1) viscous pressure drop, (2) hydrostatic pressure drop, (3) interfacial pressure drop and (4) penetration theory for mass transfer, it has been demonstrated that two-phase laminar bubble-train flow in small channels can exhibit better mass transfer for a given power input than turbulent contactors. 

Thulasidas, T. C., Abraham, M. A., Cerro, R. L. (1997). Flow patterns in liquid slugs during bubble-train flow inside capillaries. Chemical Engineering Science, 52, 2947-2962. 

Bubble train flow Elongated bubble flow Intermittent flow Plug flow Segmented flow Slug flow Taylor bubble flow... 

The analytical model developed by Thulasidas et al. [6], which is suitable for bubble train flow, showed that the transition to complete bypass (pattern 2a) occurs in horizontal flow at Ca = 0.7, in upward flow at Ca = 0.5, and in downward flow at Ca = 0.6. 

T.C. Thulasidas, M.A. Abraham, R.L. Cerro, Dispersion during bubble train flow in capillaries, Chem. Eng. Sci, 1999, 54, 61-76. 

R. Gruber, T. Melin, Radial mass transfer enhancement in bubble-train flow. International Journal of Heat and Mass Transfer, 2003, 46, 2799-2808. 

T. C. Thulasidas, M. A. Abraham and R. L. Cerro, Bubble-train flow in capillaries of circular and square cross-section. ChemicalEn neeringScience, 1995, 50(2), 183-199. 

Eskin D, Mostowfi F. A model of a bubble train flow accompanied with mass transfer through a long microchannel. Int. J. Heat Fluid Flow 2012 33(1) 147-155. 

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