Stratification effects by fine suspended sediment at low, medium, and very high concentrations

Stratification effects by fine suspended sediment at low, medium, and very high concentrations

Winterwerp, J.C.

Civil Engineering and Geosciences

Hydraulic Engineering

2006-05-18

This paper describes results of the second part of a study on stratification effects by cohesive and noncohesive sediment. Winterwerp (2001) applied classical stratified flow theory implemented in a one-dimensional vertical numerical model (the 1DV POINT MODEL), showing that sediment-induced stratification effects may occur at already fairly small suspended sediment concentrations (i.e., a few 100 mg/L). We also discussed a basic difference between the behavior of cohesive and noncohesive sediment, which emerges as a result of the large water content of mud flocs. In this paper we elaborate further on the hydrodynamic description of the transport of fine suspended sediment by analyzing field and laboratory observations over a very large range of concentrations. We propose a sediment stability diagram to explain some features of hyperconcentrated flows, such as those observed in the Yellow River. We show that the behavior of hyperconcentrated flows is affected largely by hindered settling effects reducing the energy required to keep the sediment in suspension. The hydrodynamic description of sediment transport is used to predict capacity conditions as a function of a dimensionless stream power, i.e., U3/hgWs. This prediction agrees favorably with observations reported in literature covering four orders of magnitude in suspended sediment concentration.

stratification
fine sediment
stability diagram

http://resolver.tudelft.nl/uuid:e37ff3e5-8f2d-4800-82e8-f5bd7286dc1a

https://doi.org/10.1029/2005JC003019

American Geophysical Union

0148-0227

http://europa.agu.org/?view=article&uri=/journals/jc/jc0605/2005JC003019/2005JC003019.xml

Journal of Geophysical Research, 111, 2006

Institutional Repository

journal article

(c) 2006 Winterwerp, J.C.