Drag reduction by a linear viscosity profile.

@article{DeAngelis2004DragRB,
  title={Drag reduction by a linear viscosity profile.},
  author={Elisabetta De Angelis and Carlo Massimo Casciola and Victor S L’vov and Anna Pomyalov and Itamar Procaccia and Vasil Tiberkevich},
  journal={Physical review. E, Statistical, nonlinear, and soft matter physics},
  year={2004},
  volume={70 5 Pt 2},
  pages={
          055301
        }
}
Drag reduction by polymers in turbulent flows raises an apparent contradiction: the stretching of the polymers must increase the viscosity, so why is the drag reduced? A recent theory proposed that drag reduction, in agreement with experiments, is consistent with the effective viscosity growing linearly with the distance from the wall. With this self-consistent solution the reduction in the Reynolds stress overwhelms the increase in viscous drag. In this Rapid Communication we show, using… 

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