The State of Art of Physical Modelling of Sediment Transport
The paper attempts formula some ideas about the state of the art in the field of physical modelling of sediment transport processes. Up to now the physics of sediment transport are not...

Advances in Computational Mobile-Bed Hydraulics
A new conceptual approach to one-dimensional mobile-bed simulation is briefly described, along with two demonstrative examples. The approach is based on fully coupled solution of the unsteady...

The Formation of Meandering and Braided Channels
Flow in alluvial channels implies flow past boundaries that form and deform under the action of the flow. Interaction between the flow and the mobile boundaries produces channel patterns...

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...

Application of 2-D Model to Reduce Sedimentation Problems
The Corps of Engineers opened Lock and Dam No. 1 on the Red River Waterway in 1984. During the first runoff season, excessive quantities of fine sediment deposited in both the upstream...

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...

Friction Slope Computation for Mathematical Models
The behavior of the energy flow gradient as function of depth and velocity is analyzed for three flow resistance methods. In the paper, the necessary modifications introduced to the methods...

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...

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,...

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...

 

 

 

 

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