Bubble Shape and Film Thickness

At Ca 10 , inertial effects become important (visco-inertial regime) and the film thickens as suggested by Taylor s data. In this regime 

Computationally it was found that the influence of increasing Re on film thickness is non-monotonic where an initial decrease in thickness is followed by an increase [40]. For Ca 0.01, however, inertial forces do not have an effect on film thickness. Experimentally determined film thickness correlations were hsted by Edvinsson and Irandoust [41]. Thulasidas et al. [34] foimd experimentally in 2 mm channels that the film thickness was almost the same in horizontal and downward flows but tvrice as much in upward flow. 

For low Re, Kreutzer et al. [42] foimd that the presence of bubbles in Taylor flow increases the single-phase hquid pressure drop by an amount almost equal to the 

An empirical correlation for pressure drop has been suggested by liu et al. [29]. Based on experimental data, Cubaud and Ho [19] suggested two correlations for pressure drop for gas-liquid flows depending on the Uquid hold up Ei  

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