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Sediment Entrainment and Transport in Complex Flows

  • Jonathan M. Nelson
  • Mark W. Schmeeckle
  • Ronald L. Shreve
  • Stephen R. McLean
Chapter

Abstract

Predicting the entrainment and transport rates of sediment grains making up an erodible bed underlying an arbitrary flow field requires a mechanistic understanding of the coupling between the flow and the forces on sediment grains. To help develop such an understanding, a suite of flow and sediment-transport experiments are described; these may be loosely divided into two categories. First, measurements of near-bed flow structure and sediment motion in a variety of spatially or temporally accelerating flows are used to show the manner in which changes in flow structure can impact sediment entrainment and transport. Second, direct high-frequency measurements of lift and drag on sediment particles in various turbulent flows are used to make a more direct connection between nearbed flow structure and sediment dynamics. Taken together, these experiments show how even changes in turbulence structure due to spatial and/or temporal accelerations can have a significant effect on the sediment-transport field. Finally, a method is briefly outlined for predicting sediment motion under arbitrary flows using either measured nearbed velocity time series or flow information predicted from direct numerical simulations or large-eddy simulations.

Keywords

Sediment Transport Streamwise Velocity Sediment Flux Velocity Time Series Sediment Entrainment 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer-Verlag Berlin Heidelberg 2001

Authors and Affiliations

  • Jonathan M. Nelson
    • 1
  • Mark W. Schmeeckle
    • 2
  • Ronald L. Shreve
    • 3
  • Stephen R. McLean
    • 4
  1. 1.National Research ProgramU.S. Geological SurveyDenverUSA
  2. 2.Department of GeologyFlorida State UniversityTallahasseeUSA
  3. 3.Department of Earth and Space SciencesUCLALos AngelesUSA
  4. 4.Department of Ocean EngineeringUCSBSanta BarbaraUSA

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