Surfactant-driven instability of a divergent flow

  title={Surfactant-driven instability of a divergent flow},
  author={G. Koleski and J-C Loudet and Alexandre Vilquin and Bernard Pouligny and Thomas Bickel},
  journal={Physical Review Fluids},
Extremely small amounts of surface-active contaminants are known to drastically modify the hydrodynamic response of the water-air interface. Surfactant concentrations as low as a few thousand molecules per square micron are sufficient to eventually induce complete stiffening. In order to probe the shear response of a water-air interface, we design a radial flow experiment that consists in an upward water jet directed to the interface. We observe that the standard no-slip effect is often… 

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