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Dynamics of Compression-Driven Gas-Liquid Displacement in a Capillary Tube
Callum Cuttle1, Christopher W MacMinn1
1Department of Engineering Science, University of Oxford, Oxford OX1 3PJ, United Kingdom.
Abstract:
We study two-phase displacement via the steady compression of an air reservoir connected to an oil-filled capillary tube. Our experiments and modeling reveal complex displacement dynamics depending on compression rate and reservoir volume that, for large reservoirs, depend on a single dimensionless compressibility number. We identify two distinct displacement regimes, separated by a critical value of the compressibility number. While the subcritical regime exhibits quasisteady displacement after an initial transient, the supercritical regime exhibits burstlike expulsion.
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