A New Turbulence Model: The k-?-S Model
A new turbulence model, the k-?-S( turbulent kinetic energy-dissipation-Stochastic theory) model, is presented. Instead of the Boussinesq eddy viscosity concept in the k-? -E( turbulent...
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,...
Reliability of Bank Protection Works Subject to Erosion
Sediment movement and changes of bed levels in natural rivers are non-stationary processes. The design of protection works for structures against erosion should account for the time dependency...
Channel Entrenchment Along the Post Creek Cutoff in Southern Illinois
The Post Creek Cutoff was constructed in 1915 by the Cache River Drainage Commission to divert flow from the Upper Cache River to the Ohio River. The construction of the cutoff reduced...
Model Study of Side Slope Riprap
Laboratory experiments were conducted in 10-m long channels having 1.5 H : 1 V side slopes protected with a 20.7-mm diameter rock layer 1.5 diameters thick. Four models were tested. In...
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)...
Using Sediment-Threshold Theories in Waves and Currents
Fundamentally different threshold-of-motion theories were applied to sand transport in two different coastal environments. Several recommendations for threshold application were reached....
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...
100 Years of Sedimentation Study by the USGS
On January 15, 1889, the U.S. Geological Survey began collecting sediment data on the Rio Grande at Embudo, New Mexico. During the past 100 years the U.S. Geological Survey's...
History of the Federal Interagency Sedimentation Project
Since 1939, the date of the Project's inception, the team has operated under the direction of two lead agencies - the U.S. Geological Survey and U.S. Army Corps of Engineers....
Erosion and Sedimentation Research in ARS
The paper presents a brief history of the growth of the erosion and sedimentation research program in the Agricultural Research Service of the U.S. Department of Agriculture. Subjects...
Corps of Engineers' Mississippi River Sediment Studies
In conjunction with the 1838 U.S. Army Corps of Engineers hydrographic survey of the Mississippi River, CPT A. Talcott collected sediment samples in the passes 'to determine...
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...
Instability of Bed-Surface Composition Due to Sorting Process in a Stream Composed of Sand and Gravel
Wavy patterns of sorting are often observed in a stream composed of sand and gravel, and they are regarded as instability of bed-surface composition due to selective bed-load transport...
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