On the role of turbulent large-scale streaks in generating sediment ridges

  title={On the role of turbulent large-scale streaks in generating sediment ridges},
  author={Markus Dr. Scherer and Markus Uhlmann and Aman G. Kidanemariam and Michael Krayer},
  journal={Journal of Fluid Mechanics},
Abstract The role of turbulent large-scale streaks or large-scale motions in forming subaqueous sediment ridges on an initially flat sediment bed is investigated with the aid of particle resolved direct numerical simulations of open channel flow at bulk Reynolds numbers up to 9500. The regular arrangement of quasi-streamwise ridges and troughs at a characteristic spanwise spacing between 1 and 1.5 times the mean fluid height is found to be a consequence of the spanwise organisation of… 
On the existence and formation of multi-scale particle streaks in turbulent channel flows
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