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arXiv · 1008.4595

Viscoelastic Suppression of Gravity-Driven Counterflow Instability

P. Beiersdorfer·D. Layne·E. W. Magee·J. I. Katz
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Abstract

Attempts to achieve "top kill" of actively flowing oil wells by insertion of dense drilling "muds", i.e., slurries of dense minerals, from above will fail if the Kelvin-Helmholtz instability in the gravity-driven counterflow produces turbulence that breaks up the denser fluid into small droplets. Here we estimate the droplet size to be sub-mm for fast flows and suggest the addition of a shear-thickening polymer to suppress turbulence. Laboratory experiments show a progression from droplet formation to complete turbulence suppression at the relevant high velocities, illustrating rich new physics accessible by using a shear-thickening liquid in gravity driven counter-streaming flows.

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P. Beiersdorfer, D. Layne, E. W. Magee, J. I. Katz. 2010-12-14. Viscoelastic Suppression of Gravity-Driven Counterflow Instability. https://doi.org/10.1103/physrevlett.106.058301

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