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...
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...
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...
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...
The Structure of Intermittent Sand Suspension Events Under Mild Wave Conditions
Nearshore sedimentation processes are being actively investigated through a series of research projects at the University of Miami. Quantitative measurements of waves, currents, and suspended...
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...
Sediment Transport Due to Turbidity Currents
The processes of sediment transport in a horizontal channel due to low-Reynolds-number turbidity currents are evaluated. A multiple-layer numerical model was developed to predict the flow...
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...
Estimating Velocity and Scour in River Bends
A one-dimensional, steady-state, stream tube model was used to simulate hydraulic characteristics at a cross section. This enabled computation of higher velocities on the outside and lower...
Bank Failure and Erosion on the Illinois Waterway
In 1988, bank failure and erosion on the Illinois Waterway were evaluated. Banks were inspected from the air and from a motor vessel; thirty-one sites were examined in detail. Severe erosion...
Exceedance of Allowable Velocity in Bank Stability
The authors have developed a method to account for flow duration in the application of the allowable velocity method through comparison with observed bank instabilities on a river system....
Laboratory Analysis of Hyperconcentrations
The physical and kinematic behavior of hyperconcentrations has been reviewed and a summary of recent and past developments in hyperconcentrated flow research is presented. This paper focuses...
Bed Topography and Sorting in Alluvial Channel Bends
A quasi-three-dimensional model has been developed for the purpose of calculating the velocity distribution, the bed topography and sediment sorting along channel bends. The depth-averaged...
Boundary Conditions of Tidal Model at River Mouth
A small grid is required to schematize irregular shape of shoreline in the vicinity of river mouth which limits the modeling area to be small. Tidal records along the boundary show no...
Sorting of Mixed Sand on a Two-Dimensional Beach
A numerical method is developed to predict temporal variations of the sea bed topography and the bed-material composition. The predicted results are compared with the measurements in a...
Groins and Vanes Developed Basing Upon a New Concept of Bank Protection
At curved bends, scour at the outer bank always accompanies deposition at the inner bank. A highly efficient river course for flood flow is considered to have a small lateral gradient...
Cellular Automaton Simulation of Viscous Free Surface Fluid Dynamics
It has been demonstrated elsewhere that the simple interaction of a two dimensional field of discrete particles traveling on a regular lattice yields large scale behavior closely approximating...
Verification of Local Modes in a Two-Dimensional Tidal Model
Based on a generalized model equation, a two-dimensional hybrid finite element model has been developed to study tidal waves of incompressible, homogeneous fluid in rotational flows. In...
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