Critical-Layer Structures and Mechanisms in Elastoinertial Turbulence.
@article{Shekar2018CriticalLayerSA, title={Critical-Layer Structures and Mechanisms in Elastoinertial Turbulence.}, author={Ashwin Shekar and R. M. McMullen and Sung-Ning Wang and Beverley J. McKeon and Michael D. Graham}, journal={Physical review letters}, year={2018}, volume={122 12}, pages={ 124503 } }
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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