Comparison of n Values in Natural and Dredged Channels
Manning's n values were determined for three stream channels in two complex watersheds in North Mississippi. The study covered a wide range of channel conditions and flow...

Derivation of a Stability Principle from the Shields Criterion
The widely used specific energy equation, which defines the subcritical and supercritical states of the open channel flow, is a direct result of the integration of the Froude number corresponding...

Self-Accelerated Turbidity Current Prediction Based Upon Dynamic Turbulence Models
The structure of a self-accelerated turbidity current appears to be significantly better predicted by a dynamic Reynolds stress turbulence model than by one- and two- equation models....

Modeling Sediment Transport in Rectangular Ducts with a Two-Equation Model of Turbulence
The paper deals with the application of a two-equation model of turbulence to the calculation of flows in rectangular ducts. A non-linear relationship is used to link the Reynolds stresses...

Mathematical Models for Turbulent Shear Stress in Sediment-Laden Flows
Turbulent shear stress in sediment-laden flows has been examined by several investigators including H.A. Einstein and N. Chien A. Zagustin and J.C. Willis. Three derivations resulted in...

Weighted Finite Difference Method for Diffusive Transport
The purpose of the paper is to present an application of a new method to the two-dimensional, transient advective-diffusive transport in both turbulent flow of viscous fluid and seepage...

An Alternative Approach to Erosion Control and Mitigation
A case study is presented in which a sediment engineering investigation was conducted to determine the potential effects of a change in flow regulation on the channel downstream of a lake,...

Wave?Current Interaction and Sediment Transport
The paper reports on a study into whether a close relationship between the mixing (diffusion) coefficient for the sediment, ?s, and the mixing (diffusion)...

Transport of Grain-Water Mixture by Waves
The numerical modelling of the morphological changes of coastal regions is hampered by the multiplicity of empirical sediment transport formulae. The paper discusses the modes of transport...

Towards a Distinct Treatment of Incipient Motion for Bed Forms of Low Regime
The principle methods for estimating the incipient particle motion on developed bed forms in the lower regime are compared with each other. Usually only a part of the total wall shear...

The Beginning of Sediment Transport as a Probability-Problem
Sediment transport only takes place when the action of flow (shear stress, velocity) exceeds a critical value. The limit between rest and movement can be given as critical flow velocity,...

A Continuum Mechanics Approach to Loose-Bed Motion
A mathematical model is presented for simulation of loose-bed motion. The physical system is separated into two regions, a bottom region and an upper region. The bottom region is representative...

Critical Shear Stress of Armour Coat
The problem of the determination of the critical shear stress of the armour coat is important in sediment transport, river degradation and aggradation and flow discharge regulation. The...

Integral Length Scale in Sediment-Suspending Flow
The Clauser integral length scale is an adequate scaling parameter for velocity defect profiles in clearwater and sediment-suspending flows in open channels. Velocity defect profiles plotted...

Near Bed Sediment Concentration as Influenced by Turbulence
Suspended sediment concentration profiles are developed based on the conservation of mass and conservation of momentum equations of sediment laden flows. The resulting concentration profile...

Modeling Erosion and Deposition Due to Suction and Jet Flows
PHOENICS, a commercial 3-D computational fluid dynamics software package, was modified for simulating seabed erosion and deposition. Time varying sediment fluidization, transport and deposition...

Energy Relations for Suspended Sediment Transport
One of the main difficulties in predicting transport rates of suspended sediment on the basis of the Rouse-expression for relative sediment concentrations, is the lack of any reliable...

Sediment?Hyperconcentration Flow and Its Similarity Laws
The sediment- hyperconcentration flow are studied theoretically and experimentally, and the formulas for the Bingham shear stress, rigidity coefficient, fall velocity and transport capacity...

The Effects of Velocity on Scour
Four effects of 'velocity' on scour are discussed: clear-water scour, scour by light sediment-transporting flow, mode of movement, and kinetic terms included...

Prediction of Time Development of Local Scour
The prediction of the time development of local scour is commonly solved by means of model tests. A brief description of the time-scale and the relation between the time and the scour...

 

 

 

 

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