Viscoelastic Suppression of Gravity-Driven Counterflow Instability

TL;DR

This paper investigates how adding shear-thickening polymers can suppress turbulence caused by Kelvin-Helmholtz instability in gravity-driven counterflows, potentially improving oil well

Contribution

It introduces a novel approach of using shear-thickening liquids to suppress turbulence in counterflow systems, supported by laboratory experiments.

Findings

Droplet size estimated to be sub-mm at high velocities.

Shear-thickening polymers effectively suppress turbulence.

Experimental results demonstrate transition from droplet formation to turbulence suppression.

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.