Saturation of turbulent drag reduction in dilute polymer solutions

@article{Benzi2004SaturationOT,
  title={Saturation of turbulent drag reduction in dilute polymer solutions},
  author={Roberto Benzi and Victor S L’vov and Itamar Procaccia and Vasil Tiberkevich},
  journal={EPL},
  year={2004},
  volume={68},
  pages={825-831}
}
Drag reduction by polymers in turbulent wall-bounded flows exhibits universal and non-universal aspects. The universal maximal mean-velocity profile was explained in a recent theory. The saturation of this profile and the crossover back to the Newtonian plug are non-universal, depending on Reynolds number e, concentration of polymer cp and the degree of polymerization Np. We explain the mechanism of saturation stemming from the finiteness of extensibility of the polymers, predict its dependence… 

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