World Library  


Add to Book Shelf
Flag as Inappropriate
Email this Book

Turbulent and Viscous Sediment Transport – a Numerical Study : Volume 37, Issue 37 (06/05/2014)

By Durán, O.

Click here to view

Book Id: WPLBN0003973465
Format Type: PDF Article :
File Size: Pages 8
Reproduction Date: 2015

Title: Turbulent and Viscous Sediment Transport – a Numerical Study : Volume 37, Issue 37 (06/05/2014)  
Author: Durán, O.
Volume: Vol. 37, Issue 37
Language: English
Subject: Science, Advances, Geosciences
Collections: Periodicals: Journal and Magazine Collection, Copernicus GmbH
Historic
Publication Date:
2014
Publisher: Copernicus Gmbh, Göttingen, Germany
Member Page: Copernicus Publications

Citation

APA MLA Chicago

Andreotti, B., Claudin, P., & Durán, O. (2014). Turbulent and Viscous Sediment Transport – a Numerical Study : Volume 37, Issue 37 (06/05/2014). Retrieved from http://www.ebooklibrary.org/


Description
Description: Laboratoire de Physique et Mécanique des Milieux Hétérogènes, PMMH UMR 7636 ESPCI – CNRS – Université Paris-Diderot – Université P.M. Curie, 10 rue Vauquelin, 75005 Paris, France. Sediment transport is studied as a function of the grain to fluid density ratio using two phase numerical simulations based on a discrete element method (DEM) for particles coupled to a continuum Reynolds averaged description of hydrodynamics. At a density ratio close to unity (typically under water), sediment transport occurs in a thin layer at the surface of the static bed, and is called bed load. Steady, or saturated transport is reached when the fluid borne shear stress at the interface between the mobile grains and the static grains is reduced to its threshold value. The number of grains transported per unit surface therefore scales as the excess shear stress. However, the fluid velocity in the transport layer remains almost undisturbed so that the mean grain velocity scales with the shear velocity u*. At large density ratio (typically in air), the vertical velocities are large enough to make the transport layer wide and dilute. Sediment transport is then called saltation. In this case, particles are able to eject others when they collide with the granular bed. The number of grains transported per unit surface is selected by the balance between erosion and deposition and saturation is reached when one grain is statistically replaced by exactly one grain after a collision, which has the consequence that the mean grain velocity remains independent of u*. The influence of the density ratio is systematically studied to reveal the transition between these two transport regimes. Finally, for the subaqueous case, the grain Reynolds number is lowered to investigate the change from turbulent and viscous transport.

Summary
Turbulent and viscous sediment transport – a numerical study

Excerpt
Baas, A. C. W.: Challenges in aeolian geomorphology: investigating aeolian streamers, Geomorphology, 93, 3–16, 2008.; Bagnold, R. A.: The flow of cohesionless grains in fluids, Phil. Trans. R. Soc. Lond., 249, 235–297, 1956.; Camemen, B. and Larson, M.: A general formula for non-cohesive bed-load sediment transport, Estur. Coast., 63, 249–260, 2005.; Carneiro, M. V., Pähtz, T., and Herrmann, H. J.: Jump at the onset of saltation, Phys. Rev. Lett., 107, 098001, doi:10.1103/PhysRevLett.107.098001, 2011.; Charru, F.: Selection of the ripple length on a granular bed, Phys. Fluids, 18, 121508, doi:10.1063/1.2397005, 2006.; Charru, F., Mouilleron, H., and Eiff, O.: Erosion and deposition of particles on a bed sheared by a viscous flow, J. Fluid Mech., 519, 55–80, 2004.; Creyssels, M., Dupont, P., Ould el Moctar, A., Valance, A., Cantat, I., Jenkins, J. T., Pasini, J. M., and Rasmussen, K. R.: Saltating particles in a turbulent boundary layer: experiment and theory, J. Fluid Mech., 625, 47–74, 2009.; Discrete-element Modeling of Granular Materials, edited by: Radja\\i F. and Dubois, F., ISTE, Wiley, 2011.; Durán, O., Claudin, P. and Andreotti, B.: On aeolian transport: grain-scale interactions, dynamical mechanisms and scaling laws, Aeolian Res., 3, 243–270, 2011.; Durán, O., Andreotti, B., and Claudin, P.: Numerical simulation of turbulent sediment transport, from bed load to saltation, Phys. Fluids, 24, 103306, 2012.; Ferguson, R. I. and Church, M.: A simple universal equation for grain settling velocity, J. Sedim. Res., 74, 933–937, 2004.; Greeley, R., Blumberg, D. G., and Williams, S. H.: Field measurement of the flux and speed of wind blown sand, Sedimentology, 43, 41–52, 1996.; Houssais, M. and Lajeunesse, E.: Bedload transport of a bimodal sediment bed, J. Geophys. Res., 117, F04015, 2012.; Iversen, J. D. and Rasmussen, K. R.: The effect of wind speed and bed slope on sand transport, Sedimentology, 46, 723–731, 1999.; Kok, J. F., Renno, N. O.: A comprehensive numerical model of steady state saltation (COMSALT), J. Geophys. Res., 114, D17204, 2009.; Lajeunesse, E., Malverti, L., and Charru, F. Bedload transport in turbulent flow at the grain scale: experiments and modeling, J. Geophys. Res., 115, F04001, 2010.; Meyer-Peter, E. and Müller, R.: Formulas for bed load transport, Proc., 2nd Meeting, IAHR, Stockholm, Sweden, 39–64, 1948.; Le Louvetel-Poilly, J., Bigillon, F., Doppler, D., Vinkovic, I., and Champagne, J.-Y.: Experimental investigation of ejections and sweeps involved in particle suspension, Water Resour. Res., 45, W02416, 2009.; Marchioli, C., Armenio, V., Salvetti, M. V., and Soldati, A.: Mechanisms for deposition and resuspension of heavy particles in turbulent flow over wavy interfaces, Phys. Fluids, 18, 025102, 2006.; Mouilleron, H., Charru, F., and Eiff, O.: Inside the moving layer of a sheared granular bed, J. Fluid Mech., 628, 229–239.; Owen, P. R.: Saltation of uniform grains in air, J. Fluid Mech., 20, 225–242, 1964.; Pope, S. B.: Turbulent flows, Cambridge University Press, 2000.; Rasmussen, K. R., Iversen, J. D., Rautaheimo, P.: Saltation and wind flow interaction in a variable slope wind tunnel. Geomorphology, 17, 19–28, 1996.; Ribberink, J. S.: Bed-load transport for steady flows and unsteady oscillatory flows, Coastal Eng., 34, 58–82, 1998.; Ungar, J. E. and Haff, P. K.: Steady state saltation in air, Sedimentology, 34, 289–299, 1987.

 

Click To View

Additional Books


  • The Future Climate Characteristics of th... (by )
  • Analysis of Highly Accurate Rain Intensi... (by )
  • Near-source Observations and Modeling of... (by )
  • Integration of Onshore and Offshore Seis... (by )
  • The Morphodynamic Responses of Artificia... (by )
  • Statistical and Neural Classifiers in Es... (by )
  • Gauging the Ungauged Basin: a Top-down A... (by )
  • From Inferential Statistics to Climate K... (by )
  • Modelling of Long Term Nitrogen Retentio... (by )
  • Srtm Dem Levels Over Papyrus Swamp Veget... (by )
  • Space Weather and Risk Management : Volu... (by )
  • Application of the Mm5 and the Analogous... (by )
Scroll Left
Scroll Right

 



Copyright © World Library Foundation. All rights reserved. eBooks from World eBook Library are sponsored by the World Library Foundation,
a 501c(4) Member's Support Non-Profit Organization, and is NOT affiliated with any governmental agency or department.