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arXiv · 1208.4538

Effective Rheology of Bubbles Moving in a Capillary Tube

Santanu Sinha·Alex Hansen·Dick Bedeaux·Signe Kjelstrup
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Abstract

We calculate the average volumetric flux versus pressure drop of bubbles moving in a single capillary tube with varying diameter, finding a square-root relation from mapping the flow equations onto that of a driven overdamped pendulum. The calculation is based on a derivation of the equation of motion of a bubble train from considering the capillary forces and the entropy production associated with the viscous flow. We also calculate the configurational probability of the positions of the bubbles.

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Santanu Sinha, Alex Hansen, Dick Bedeaux, Signe Kjelstrup. 2012-08-22. Effective Rheology of Bubbles Moving in a Capillary Tube. https://doi.org/10.1103/physreve.87.025001

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