Potential Flow Over a Wavy Bed: A Persistent Error
The standard small-amplitude theory of potential flow over a wavy bed is briefly discussed, together with the three special values of the Froude Number which define four different flow...

Bed Waves Generated by Internal Waves in Alluvial Channels
The flow in an alluvial channel is conceived as a stratified flow both with respect to the velocity- and density-distribution. In such flows internal waves may occur which influence the...

A Tracer-Model for Morphological Simulations of an Estuary
Numerical models for longterm morphological simulations are traditionally based on assumptions like vertical integration of the flow and transport equations and their decoupled treatment....

On the Numerical Simulation of Suspended Sediment Transport in Estuaries
Estuarine fine sediment transport is governed by a wide range of hydrological, chemical and biological parameters including baroclinic circulation, tidal pumping, resuspension, deposition,...

Storms and the Occurrence of a Turbidity Interface/Maxima in a Fresh Water Estuary
A combination of Landsat, field data and modeling analyses reveals a turbidity interface/maxima in the lower reaches of a freshwater tributary or 'estuary.' Mode...

Modeling of Contaminant Transport in Rivers with Emphasis on the Interaction with Movable Boundaries
The transport of dissolved and absorbed pollutants is simulated by a one-dimensional convection-diffusion model which particularly accounts for the exchange processes at the river bed...

Modelling Changes in Coastal Morphology
A description is given of a newly-developed coastal sediment transport model. Features of the model are the inclusion of cross-shore transport and non-potential suspended load, the latter...

Modelling of Sand Bars in Coastal Environments
A mathematical model describes the formation of sand bars by progressive wind-generated waves. The model decomposes into several constituents linked together in a two step morphological...

A Method to Treat Incident Wave Condition in Shallow Water Equation
A method to consider open boundary condition of the shallow water equation to analyze water surface wave and tide is employed in the finite element anaysis. This can be done by considering...

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...

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...

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...

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,...

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...

Implications of Deep Ocean Modelling on Coastal Sedimentation Prediction
The Harvard University Ocean Predictive Descriptive System is reviewed and recent results of mesoscale ocean prediction are presented for the Northeast Pacific and Gulf Stream Ring Stream...

A Finite Element Application of Sand Terrace Formation Process
In this paper, the formation process of a sand terrace in front of river mouth is simulated numerically by means of the finite element method. The two-step explicit scheme is applied as...

Mid-Scale Laboratory Tests on a Two-Dimensional Movable-Bed Sand Model
A two-dimensional physical model was used to simulate wave-induced scour in front of a concrete dike sloped at 1:4. The tests were conducted at the U.S. Army Engineers Waterways Experiment...

 

 

 

 

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