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 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… 
Open-channel flow over evolving subaqueous ripples
Abstract We have numerically investigated the turbulent flow and sediment grain motion in an open-channel flow configuration over a subaqueous sediment bed featuring two-dimensional transverse
On the existence and formation of multi-scale particle streaks in turbulent channel flows
Abstract Direct numerical simulations of particle-laden turbulent channel flows at friction Reynolds number $Re_\tau$ from $600$ to $2000$ have been performed to examine the near-wall particle
Role of the hierarchy of coherent structures in the transport of heavy small particles in turbulent channel flow
Abstract To investigate the transport of heavy small particles (inertial particles) in high-Reynolds- number wall turbulence, we conduct direct numerical simulations of inertial particles in
Causality between fluid motions and bathymetric features
  • T. Hsu
  • Physics
    Journal of Fluid Mechanics
  • 2022
Abstract Can morphodynamic problems be solved using a first-principles approach in multiphase fluid mechanics? This is the holy grail for many sediment transport researchers but has yet to be
Bottom wall shear stress fluctuations in shallow-water Langmuir turbulence
Abstract In neutrally stratified shallow water, full-depth Langmuir cells (LCs) can interact with the turbulent benthic boundary layer and, thus, influence bottom wall shear stresses. In this paper
The effect of spanwise heterogeneous roughness on mixed convection in turbulent channels
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