Critical-Layer Structures and Mechanisms in Elastoinertial Turbulence.

  title={Critical-Layer Structures and Mechanisms in Elastoinertial Turbulence.},
  author={Ashwin Shekar and Ryan Michael McMullen and Sung-Ning Wang and Beverley J. McKeon and Michael D. Graham},
  journal={Physical review letters},
  volume={122 12},
Simulations of elastoinertial turbulence (EIT) of a polymer solution at low Reynolds number are shown to display localized polymer stretch fluctuations. These are very similar to structures arising from linear stability (Tollmien-Schlichting modes) and resolvent analyses, i.e., critical-layer structures localized where the mean fluid velocity equals the wave speed. Computations of self-sustained nonlinear Tollmien-Schlichting waves reveal that the critical layer exhibits stagnation points that… 

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