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document
Van Bendegom, L. (author)
report 1974
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Ribberink, J.S. (author)
In Chapter I a derivation of the equations and an extension of the mathematical model will be carried out. The sediment-mixture is separated in a number of fractions - each with a representative grain size - and the equations describing the sediment-movement are split up for every fraction separately. In order to get some insight in the new...
report 1980
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Talmon, A.M. (author)
A two dimensional depth-averaged model for the concentration field of suspended sediment in river bend flow is formulated. Transport of suspended sediment in horizontal and vertical directions is modelled. Convection by the main and secondary flow and turbulent diffusion are incorporated. The model is capable of computing the exchange of...
report 1989
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Mosselman, E. (author)
Bank erosion is incorporated in one-dimensional and two-dimensional horizontal models for river morphology. The banks are assumed to consist of a fraction of cohesive material, which becomes washload after being eroded, and a fraction of granular material, with the same properties as the material of the bed. The banks are taken to be eroded by...
report 1989
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Crosato, A. (author)
A simple mathematical model for the simulation of river meandering processes is presented and analysed. The model is schematized as follows: computation of steady-state flow field and riverbed topography; and computation of bank erosion rate as a function of the near-bank hydraulic and morphological properties. The model is linear for the...
report 1990
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Mosselman, E. (author)
A numerical two-dimensional model for river morphology is extended with bank erosion. The model is formulated in curvilinear coordinates. This allows the use of a boundary-fitted computational grid, suited for rivers with a curved centre-line and a non-uni form width. Dealing with non-homogeneous bank erodibility is shown to require a non...
report 1991
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Sieben, J. (author)
Present knowledge on fluvial processes in mountain rivers should be expanded to enable the development of projects dealing with mountain rivers or mountain-river catchment areas. This study reviews research on hydraulic and morphological features of mountain rivers. A major characteristic of mountain rivers is the variability of the hydraulic...
report 1993
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De Vries, M. (author)
In Chapter 2 of this report an overview is given on fluvial processes involved in the modelling discussed. Chapter 3 is concerned with scale models, whilst Chapter 4 deals with numerical models. The main problems treated are, firstly, modelling of the water movement, followed by sediment transport and morphology. Attention is also given to the...
report 1993
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De Vries, M. (author)
One dimension models - basic eauations, analytical models, numberical models. One dimensional models -suspended load, roughness and resistance of river beds. Solving river problems - tools, flood mitigation, bank protection.
lecture notes 1993
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Sieben, A. (author)
The ability of describing and predicting hydraulic and morphological phenomena in mountain rivers is limited, partially due to the limits of deterministic approaches where stochastic effects in sediment supply and water inflow are extremely significant, and partially due to the very specific conditions that can be observed in mountain rivers,...
report 1994
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Van Kuik, C.A. (author), Van Mazijk, A. (author)
In the one-dimensional 'Rhine Alarm Model' differences between the actual travel time of a pollution cloud, originating from an instantaneous release of an accidental spill, and the travel time, based on the flow velocity is represented by a lag coefficient. In the model this lag coefficient is defined by the relative difference between these...
report 1994
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Sieben, A. (author)
This report focusses on discontinuous behaviour of hydraulics and morphology in rivers. The varying widths, slopes and bed levels that can be observed in mountain rivers can induce rapid, or discontinuous changes at a short lengthscale. When present, these discontinuities have a major impact on changes in water and bed levels during floods. In...
report 1995
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Sieben, A. (author)
In this report, some classical and new simplifications in mathematical and numerical models for river morphology are compared for conditions representing rivers in mountainous areas (high values of Froude numbers and relatively large values of sediment transport rates). Options for simplification are summarized based on time scale of hydrographs...
report 1996
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Kranenburg, C. (author)
A derivation is presented of a general cross-section averaged model of longitudinal dispersion, which is based on the notion of the advection of tracer particles. Particle displacement length and particle travel time are conceived as stochastic variables, and a joint probability density function is introduced to arrive at an integral advection...
report 1996
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Yossef, M.F.M. (author)
Groynes are structures constructed at an angle to the flow in order to deflect the flowing water away from critical zones. They are made of stone, gravel, rock, earth, or piles, beginning at the riverbank with a root and ending at the regulation line with a head. They serve to maintain a desirable channel for the purpose of flood control,...
report 2002
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Van Prooijen, B.C. (author), Uijttewaal, W.S.J. (author)
The development of large coherent structures in a shallow mixing layer is analyzed. The results are validated with experimental data obtained from particle tracking velocimetry. The mean flow field is modeled using the self-similarity of the velocity profiles. The characteristic features of the down-stream development of a shallow mixing layer...
journal article 2002
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Marchand, M. (author)
report 2003
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Yossef, M.F.M. (author)
Report on a physical scale model test in the Fluid Mechanics lab on the effect of groynes on the bed and sediment transport in rivers.
report 2003
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Hoogendoorn, R.M. (author)
Studies in stratigraphy are often driven by the predicted climate change and possible gains for the oil and gas industry. Because, at present predictions of the development of future deltaic architecture are insufficient. This thesis addresses the problem of qualitative and quantitative understanding of sedimentary systems in two stages. In the...
doctoral thesis 2006
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Snellen, M. (author), Siemes, K. (author), Simons, D.G. (author)
We present a method for accurately estimating the bathymetry from multi-beam echo-sounder (MBES) travel-time measurements in environments with large variations in the water column sound speeds (both temporally and spatially). In this type of environments the water column sound speeds at the time of the MBES transmission are often not known,...
conference paper 2009
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