|Dynamics of concentrated benthic suspension layers|
Winterwerp, J.C.; Bruens, A.W.; Gratiot, N.; Kranenburg, C.; Mory, M.; Toorman, E. A. (2002). Dynamics of concentrated benthic suspension layers, in: Winterwerp, J.C. et al. (Ed.) Fine sediment dynamics in the marine environment. Proceedings in Marine Science, 5: pp. 41-55
In: Winterwerp, J.C.; Kranenburg, C. (Ed.) (2002). Fine sediment dynamics in the marine environment. Proceedings in Marine Science, 5. Elsevier: Amsterdam. ISBN 0-444-51136-9. XV, 713 pp., more
In: Proceedings in Marine Science. Elsevier: New York. ISSN 1568-2692, more
Buoyancy; Entrainment; Fluid mud; Mixing (sediments); Suspended sediments; Marine
Concentrated Benthic Suspensions; fluid mud; entrainment; mixing; buyoancy
|Project|| Top | Authors |
- Prediction of cohesive sediment transport and bed dynamics in estuaries and coastal zones with integrated numerical simulation models, more
|Authors|| || Top |
- Winterwerp, J.C., more
- Bruens, A.W.
- Gratiot, N.
- Kranenburg, C.
- Mory, M.
- Toorman, E. A., more
This paper describes the dynamics of Concentrated Benthic Suspensions (CBS). CBS is defined as a suspension of cohesive sediment with a notable interaction between the sediment and the turbulent flow field through buoyancy effects, but still displaying near-Newtonian behaviour. The mechanisms which distinguish CBS from low-concentrated suspensions are described, and the focus is on the (hindered) settling and mixing processes. Experiments were carried out in an oscillating grid tank and in an rotating annular flume, simulating entrainment and mixing associated with the turbulent CBS-layer, as occur in tide-driven flows. It is shown that CBS can be modelled as a viscous fluid, and that the entrainment rates quantitatively match relations described in the literature on salt-fresh water induced stratified systems. Numerical simulations with one-dimensional vertical models using k-?: and Prandtl mixing length turbulence closures were carried out for hypothetical open channel flows to study the behaviour of CBS through sensitivity analyses. It is shown that high-concentrated mud suspensions may become saturated, generating a CBS-layer prior to the formation of fluid mud.