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International Journal of sediment Research 2000年第4期 410-423页

作者： BAI Yuchuan, SHEN Huanting, and HU Shixiong ( Asso. Prof. Dr., Institute for sedimentation on River and Coast Engineering, Tianjin University, Tianjin, 300072, China 2 Prof., The State Key Laboratory of Estuarine and Coastal Research, East China Normal Un

A 3-D numerical model for simulating tidal flow and sediment transport in the estuarine regions is presented in this paper. The model adopts -coordinate system and carries out -coordinate transformation to the basic equations, which ensure that all horizontal area has equal numbers of calculation points in vertical direction, this method provides higher distinguishable rate to the flow and sediment transport. Under the -coordinate system, the Galerkin finite-element method is applied for horizontal domain by using a new specially interpolating shape functions, while a finite difference approximation is employed over depth. The model can be used even in the situations with a considerable variety in the water depth in the computational domain. The model is verified by a test for which analytical solutions are available and then applied to simulate the tidal current and sediment transport of the Haihe River Mouth. A modeling system of sediment transport is established for applying to muddy estuary of North China. The comparison with the field data shows that the model can well simulate the evolution process in the estuary.

关键词： Three dimensional mathematical model Estuarine region -coordinate system sediment transport

DEPTH-AVERAGE ANALYSIS OF HYSTERESIS BETWEEN FLOW AND sediment transport UNDER UNSTEADY CONDITIONS

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International Journal of sediment Research 2006年第2期21卷 101-112页

作者： Mustafa ALTINAKAR Sam S.Y.WANG National Center for Computational Hydroscience and Engineering The University of Mississippi MS 38677 USA Res. Prof. National Center for Computational Hydroscience and Engineering The University of Mississippi MS 38677 USA Prof.

A depth-averaged two-dimensional model has been established to simulate unsteady flow and sediment transport in streams. The difference in flow and sediment velocities is considered. It has been found that the depth-averaged suspended-sediment velocity and the bed-load velocity are smaller than the depth-averaged flow velocity, inducing a time lag between water and sediment transport. The significance of this time lag increases as the sediment size increases. The exchange between the moving sediment and the bed material, which may induce a spatial lag, is modeled by a non-equilibrium transport approach. Tests using laboratory and field measurements have shown that the established model is capable of capturing the hysteresis between flow and sediment transport under unsteady conditions. It is demonstrated that the hysteresis is larger when the hydrograph has steeper rising and falling limbs, and the time delay increases downstream.

关键词： Hysteresis Temporal and spatial lags Unsteady flow sediment transport Depth- averaged 2-D model Non-equilibrium transport

OPTIMAL MODE OF sediment transport BY SHALLOW FLOWS IN UPLAND AREAS

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International Journal of sediment Research 2000年第2期 260-267页

作者： D. PAL S. N. PRASAD (Department of Civil Engineering, University of Mississippi, University, MS 38677, USA.) M. J. M. ROMKENS(USDA ARS National sedimentation Laboratory, Oxford, MS 38655, USA.)

Soil erosion and sediment movement are serious problems of upland areas of a watershed. In these areas,most of the eroded sediment is transported in overland flows; either in shallow or in concentrated flowsituations. These flows are usually associated with nonlinear waves, generally known as "roll waves" inthe hydraulic engineering literature. Under suitable hydraulic conditions, these waves contain a significantfraction of the total kinetic energy of the flow regime. Hence, the waves act as the primary energy sourcein transporting eroded sediment in shallow flows on steep slopes. Our laborat0ry experiments undercontrolled condition suggest that modulation of the roll waves is effected by the addition of increasingamouflts of sediment in the flow. The optimal condition in the sediment transport rate is reached whenmost of the available wave energy is consumed in carrying the sediment. A related set of experiments ongravitational flows of dry granular material show that the evolving scales of sediment waves are intrinsicto the transport mechanism of the solid phase.

关键词： Upland areas sediment transport Shallow flows Wave modes Granular organization

SUSPENDED sediment transport CAPACITY OF OPEN CHANNEL FLOW

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International Journal of sediment Research 1997年第3期 1-10页

作者： Zhixian Cao Prot. Dr.-Ing.. Director of Institute of Hydraulic Engineering, Tianjin University. Tianjin 300072. China. Wensheng WangSenior Engineer, Associate Director of Lower Haihe River Administration Bureau. Ministry of Water Resources. Tianjin 300061

A turbulent bursting-based formulation for suspended sediment transport capacity is verified with data from Brownlie (1981). Previous formulations are examined using the results of data analysis. Satisfactory performance of the turbulent bursting-based formulation is demonstrated, in addition to its strong physical background. Einstein’s formula is found to over-or under-estimate sediment transport capacity in some cases. Celik and Rodi’s correlation is shown to behave poorly. The WUHEE curve does not fit the measured data well. Further, the transport capacity is exhibited to increase nonlinearly with the nondimensional quantity u3 /ghw. This behavior upsets many existing formulas, in which the transport capacity is represented as linear functions of U3 /ghw. It is suggested that existing formulations be used cautiously, and more wellgrounded developments based on turbulent bursting be pursued.

关键词： sediment transport capacity sediment entrainment near-bed sediment concentration turbulent bursting sediment transport open channel flow

Numerical Modeling of sediment transport and Its Effect on Algal Biomass Distribution in Lake Pontchartrain Due to Flood Release from Bonnet CarréSpillway

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Journal of Geoscience and Environment Protection 2016年第9期4卷 64-79页

作者： Xiaobo Chao Yafei Jia A. K. M. Azad Hossain National Center for Computational Hydroscience and Engineering University of Mississippi Oxford USA

In order to protect the city of New Orleans from the Mississippi River flooding, the Bonnet Carré Spillway (BCS) was constructed from 1929 to 1936 to divert flood water from the river into Lake Pontchartrain and then into the Gulf of Mexico. During the BCS opening for flood release, large amounts of freshwater, nutrients, sediment, etc. were discharged into Lake Pontchartrain, and caused a lot of environmental problems. To evaluate the environmental impacts of the flood water on lake ecosystems, a two-dimensional numerical model was developed based on CCHE2D and applied to simulate the flow circulation, sediment transport and algal biomass distribution in Lake Pontchartrain. The effect of sediment concentration on the growth of algae was considered in the model. The numerical model was calibrated using field measured data provided by USGS, and then it was validated by the BCS Opening Event in 1997. The simulated results were generally in good agreement with filed data and satellite imagery. The field observation and numerical model show that during the spillway opening for flood release, the sediment concentration is very high, which greatly restricts the growth of algae, so there is no algal bloom observed in the lake. After the closure of BCS, the sediment concentration in the lake reduces gradually, and the nutrient concentration of the lake is still high. Under these conditions, numerical results and satellite imagery showed that the chlorophyll concentration was high and algal bloom might occur.

关键词： 2D Numerical Model Flow Circulation sediment transport Algal Bloom Bonnet Carré Spillway Lake Pontchartrain

Recent Variations of Water and sediment transport in the Adjacent Area between Two Large Estuaries

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World Journal of Engineering and Technology 2024年第4期12卷 1083-1089页

作者： Dongfeng Xie Shenyang Zhang Zhejiang Institute of Hydraulics and Estuary Hangzhou China Zhejiang Key Laboratory of Estuary and Coast Hangzhou China

The Changjiang Estuary and Hangzhou Bay are adjacent large estuaries. They have close water and sediment exchanges. Over the past decades, the Changjiang Estuary and Hangzhou Bay region have been affected by human activities such as dam construction and land reclamation. Based on hydrological data at the adjacent area of the two estuaries in 2014 and 2023, this study analyzed the recent variations of water and sediment transport between the two estuaries. The results show that the flow velocities, SSC and unit width sediment transport varied with the tides, decreasing from spring tides to neap tides. In recent years, the flow velocity and SSC decreased to a certain extent. Accordingly, the unit width sediment transport also decreased, with the magnitude of change being about one-third. These observed variations may have a profound influence on the estuarine ecological systems.

关键词： Changjiang Estuary Hangzhou Bay Hydrodynamics sediment transport Estuarine Engineering

A NUMERICAL MODEL OF sediment transport IN HANDUN IRRIGATION DISTRICT

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International Journal of sediment Research 1997年第3期 283-290页

作者： GAO Jianen, Senior Engineer, North-West Hydro-technical Science Research Institute, Yangling, Shaanxi 712100, China WAN Zhaohui, Professor, China Institute of Water Resources & Hydropower Research, P.O. Box 366, Beijing 100044. China CHEN Zhicong, Profe

Based on rich field data obtained before and after the renovation, a numerical model has been developed for simulating sediment transport in the main canal of Handun Irrigation District Nonequilibrium of sediment transport non-uniform sediment and lateral diversion are considered in the model. The model is calibrated by field data. Calculated values of water stages, the amount of deposits and the sire distributions of bed material well coincide with measured ones. By applying the model the effect of the renovation is evaluated, the process of deposition in a year is analyzed. Furthermore, the principle for rational operation is put forward and some measures for further improvement are suggested.

关键词： Numerical model sediment transport Irrigation district. Deposit Renovation

DEVELOPMENT OF A SURFACE PLUME MODEL AND ITS APPLICATION TO sediment transport MODELLING OF DREDGING IN COASTAL WATERS

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International Journal of sediment Research 2000年第3期 277-287页

作者： Y. CHEN: Department of Civil & Environmental Engineering, University of Bradford, Bradford, West Yorkshire, BD7 1DP, United Kingdom P. A. MACKINNON: School of Civil Engineering, The Queen’s University of Belfast, Belfast, BT9 5AG, United Kingdom G. THOMPS

The dredging operations of trailing suction hopper dredgers discharge large quantities of fine sediment into the water and can cause a substantial increase in suspended sediment concentration, resulting in the formation of visible surface plumes. This paper describes the development of a new surface plume model for the sediment transport modelling of marine dredging. The model is based on the analytical solutions of the horizontal advection and dispersion-diffusion equation and is suitable for unsteady flows in the marine environment. The newly developed model has been applied to a proposed marine dredging feasibility study in Hong Kong to demonstrate the possible model applications.

关键词： Surface Plumes sediment transport Dredging Mathematical models Analytical solutions Water quality

MASS MOVEMENTS AND sediment transport AS A NATURAL HAZARD

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International Journal of sediment Research 1997年第3期 333-341页

作者： Wolfgang KRON Senior Hydraulic Engineer, Geosciences Research Group, Munich Reinsurance Company, 80791 Munich, Germany

Compared to other natural disasters such as earthquakes, cyclones, floods and volcanic eruptions, events related to the movement of sediment cause fewer deaths and less damage. However, considerable costs abase and numerous people lose their lives every year due to sliding slopes, debris flows, lahars, erosion of embankments, and collapses of bridges. sediment transport related disasters are not only often caused, triggered or induced by human activities, they also can be reduced or even prevented if they are anticipated through scientific and other investigations, observation of nature, and adequate treatment of artificial deposits and design of structures in rivers.

关键词： landslides sediment transport human influence economic consequences disaster prevention and mitigation

INFLUENCE OF sediment transport ON ARMORED SURFACES

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International Journal of sediment Research 2001年第2期16卷 201-206页

作者： Katinka KOLL1and Andreas DITTRICH1 1 Institute of Resources Management, Hydraulic and Rural Engineering, University of Karlsruhe, Kaiserstr. 12, 76128 Karlsruhe, Germany. Institute of Resources Management Hydraulic and Rural Engineering University of Karlsruhe Kaiserstr. 1276128 Karlsruhe Germany.

Laboratory experiments have been carried out to study the characteristics of sediment transport in steep streams. The question is discussed wether an armoured surfaces is destroyed due to the transport of material, because additional impulses are acting on it, or the layer is sheltered by the transported material, because a part of the stream power is used to move the material. According to the results of the presented experiments, in which the influence of the feeding rate and the feeding duration have been investigated, transported material reaching an armoured river section from upstream always remobilzes bed material, which is immobile under clear water flow conditions. To decide if a static armour layer is either destroyed or not, two simple criteria were chosen: one considering the grain-size distribution of the eroded bed material, and another, which referes to the amount of eroded bed material.

关键词： sediment transport Bed stability Armored layer