Searched for: author:"De Vriend, H.J."
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Li, W. (author), Su, Zhenghua (author), van Maren, D.S. (author), Wang, Z.B. (author), de Vriend, H.J. (author)
The downstream peak discharge increase during hyperconcentrated floods in the Yellow River has been attributed to bed erosion, roughness reduction and floodplain effects. While great improvements have been made on the nderstandings of the roles of bed erosion and roughness reduction, the effects of floodplain remain poorly understood. Here, as a...
journal article 2017
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van Vuren, B.G. (author), de Vriend, H.J. (author), Barneveld, Hermjan (author)
Over the course of centuries, river systems have been heavily trained for the purpose of safe discharge of water, sediment and ice, and improves navigation. Traditionally, dikes are used to be reinforced and heightened to protect countries from ever higher flood levels. Other types of solutions than technical engineering solutions, such as...
journal article 2016
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Maan, D.C. (author), van Prooijen, B.C. (author), Wang, Z.B. (author), de Vriend, H.J. (author)
Various studies have identified a strong relation between the hydrodynamic forces and the equilibrium profile for intertidal flats. A thorough understanding of the interplay between the hydrodynamic forces and the morphology, however, concerns more than the equilibrium state alone. We study the basic processes and feedback mechanisms underlying...
journal article 2015
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De Vriend, H.J. (author)
Rivers respond to changes in their geometry or their controls in various ways and at a wide range of space and time scales. The response consists of changes in properties such as cross-sectional shape and area, slope, planform pattern, bed roughness and bed sediment composition. Usually, attention for the morphological impact of engineering...
journal article 2015
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Li, W. (author), Wang, Z.B. (author), Van Maren, D.S. (author), De Vriend, H.J. (author), Wu, B.S. (author)
River floods are usually featured by a downstream flattening discharge peak whereas a downstream increasing discharge peak is observed at a rate exceeding the tributary discharge during highly silt-laden floods (hyperconcentrated floods) in China’s Yellow River. It entails a great challenge in the downstream flood defence and the underlying...
journal article 2014
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De Vriend, H.J. (author), Van Koningsveld, M. (author), Aarninkhof, S. (author)
The Netherlands has adopted a new, proactive approach to developing its extensive coastal and river works called ‘building with nature’. Rather than simply minimising or mitigating the environmental impact of harbours, navigation channels, land reclamation and flood defences, the idea is to make use of the dynamics of the natural environment and...
journal article 2014
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Nabi, M. (author), De Vriend, H.J. (author), Mosselman, E. (author), Sloff, C.J. (author), Shimizu, Y. (author)
We present a 3-D physics-based high-resolution modeling approach to the dynamics of underwater ripples and dunes. The flow is modeled by large eddy simulation on a Cartesian grid with local refinements. The sediment transport is modeled by computing pickup, transport over the bed, transport in the water column, and deposition of rigid spherical...
journal article 2013
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Nabi, M. (author), De Vriend, H.J. (author), Mosselman, E. (author), Sloff, C.J. (author), Shimizu, Y. (author)
The paper describes a numerical model for simulating sediment transport with eddy-resolving 3-D models. This sediment model consists of four submodels: pickup, transport over the bed, transport in the water column and deposition, all based on a turbulent flow model using large-eddy simulation. The sediment is considered as uniform rigid...
journal article 2013
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Li, W. (author), De Vriend, H.J. (author), Wang, Z. (author), Van Maren, D.S. (author)
High-resolution morphological modeling of fluvial processes with complex, rapidly varying flows has been limited so far by model accuracy or computational efficiency. One of the most widely used numerical algorithms is based on the total variation diminishing method, solved by either upwind or centered approaches. An upwind scheme preserves high...
journal article 2013
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Ottevanger, W. (author), Blanckaert, K. (author), Uijttewaal, W.S.J. (author), De Vriend, H.J. (author)
Reduced-order models remain essential tools for meander modeling, especially for processes at large length scales and long time scales, probabilistic simulations, rapid assessments, or when input data are scarce or uncertain. Present reduced-order meander models consider their dependent variables either as small-amplitude variations compared to...
journal article 2013
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Nabi, M. (author), De Vriend, H.J. (author), Mosselman, E. (author), Sloff, C.J. (author), Shimizu, Y. (author)
We present a three-dimensional high-resolution hydrodynamic model for unsteady incompressible flow over an evolving bed topography. This is achieved by using a multilevel Cartesian grid technique that allows the grid to be refined in high-gradient regions and in the vicinity of the river bed. The grid can be locally refined and adapted to the...
journal article 2012
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De Vriend, H.J. (author), Wang, Z.B. (author), Ysebaert, T. (author), Herman, P.M.J. (author), Ding, P. (author)
This paper compares the Yangtze Estuary in China and the Western Scheldt Estuary in The Netherlands by their morphodynamic and ecological systems, their engineering works and estuarine management issues, and the major challenges in studying them. Physically speaking, the two estuaries are very different. The Yangtze Estuary is much larger and...
journal article 2011
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Blanckaert, K. (author), De Vriend, H.J. (author)
Despite the rapid evolution of computational power, simulation of meander dynamics by means of reduced and computationally less expensive models remains practically relevant for investigation of large?scale and long?term processes, probabilistic predictions, or rapid assessments. Existing meander models are invariantly based on the assumptions...
journal article 2010
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Blanckaert, K. (author), De Vriend, H.J. (author)
In spite of its importance, little is known about the turbulence characteristics in open-channel bends. This paper reports on an experimental investigation of turbulence in one cross section of an open-channel bend. Typical flow features are a bicellular pattern of cross-stream circulation (secondary flow) and a turbulence activity in the outer...
journal article 2005
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Marciano, R. (author), Wang, Z.B. (author), Hibma, A. (author), De Vriend, H.J. (author), Defina, A. (author)
We model branching channel patterns in short tidal basins with two methods. A theoretical stability analysis leads to a relationship between the number of channels and physical parameters of the tidal system. The analysis reveals that width and spacing of the channels should decrease as the slope of the bottom profile and the Shields parameter...
journal article 2005
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K. Blanckaert, K. (author), De Vriend, H.J. (author)
journal article 2005
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Blanckaert, K. (author), De Vriend, H.J. (author)
Secondary currents are a characteristic feature of flow in open-channel bends. Besides the classical helical motion (centre-region cell), a weaker and smaller counter-rotating circulation cell (outer-bank cell) is often observed near the outer bank, which is believed to play an important role in bank erosion processes. The mechanisms underlying...
journal article 2004
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Blackaert, K. (author), De Vriend, H.J. (author)
journal article 2004
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Stive, M.J.F. (author), De Vriend, H.J. (author)
Current knowledge of hydro-, sediment and morpho-dynamics in the shoreface environment is insufficient to undertake shoreface-profile evolution modelling on the basis of first physical principles. We propose a simple, panel-type model to map observed behaviour. The internal dynamics are determined by slope-dependent, wave-induced cross-shoreface...
journal article 1995
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Stive, M.J.F. (author), De Vriend, H.J. (author)
journal article 1995
Searched for: author:"De Vriend, H.J."
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