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sediment transport in headwaters of a volcanic catchment Kamchatka Peninsula case study

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Frontiers of Earth Science 2017年第3期11卷 565-578页

作者： Sergey R. CHALOV Anatolii S. TSYPLENKOV Jan PIETRON Aleksandra S. CHALOVA Danila I. SHKOLNYI Jerker JARSJO Michael MAERKER Faculty of Geography M. V. Lomonosov Moscow State University Moscow 119911 Russia Department of Physical Geography and the Bolin Centre for Climate Research Stockholm University Stockholm 10691 Sweden Department of Earth and Environmental Sciences Pavia University Pavia 27100 Italy

Due to specific environmental conditions, headwater catchments located on volcanic slopes and valleys are characterized by distinctive hydrology and sediment transport patterns. However, lack of sufficient monitoring causes that the governing processes and patterns in these areas are rarely well understood. In this study, spatiotemporal water discharge and sediment transport from upstream sources was investigated in one of the numerous headwater catchments located in the lahar valleys of the Kamchatka Peninsula Sukhaya Elizovskaya River near Avachinskii and Koryakskii volcanoes. Three different subcatchments and corresponding channel types （wandering rivers within lahar valleys, mountain rivers within volcanic slopes and rivers within submountain terrains） were identified in the studied area. Our measure- ments from different periods of observations between years 2012-2014 showed that the studied catchment was characterized by extreme diurnal fluctuation of water discharges and sediment loads that were influenced by snowmelt patterns and high infiltration rates of the easily erodible lahar deposits. The highest recorded sediment loads were up to 9-104 mg/L which was related to an increase of two orders of magnitude within a one day of observations. Additionally, to get a quantitative estimate of the spatial distribution of the eroded material in the volcanic substrates we applied an empirical soil erosion and sediment yield model - modified universal soil loss equation （MUSLE）. The modeling results showed that even if the applications of the universal erosion model to different non-agricultural areas （e.g., volcanic catchments） can lead to irrelevant results, the MUSLE model delivered might be acceptable for non-lahar areas of the studied volcanic catchment. Overall the results of our studyincrease our understanding of the hydrology and asso- ciated sediment transport for prediction of risk manage- ment within headwater volcanic catchments.

关键词： sediment transport volcanoes lahars Kam-chatka Peninsula MUSLE erosion

sediment transport simulation and design optimization of a novel marsh shoreline protection technology using computational fluid dynamics (CFD) modeling

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International Journal of sediment Research 2022年第1期37卷 14-25页

作者： Salman Saki Grant Besse Peng Yin Daniel Gang Donald Hayes Department of Civil Engineering University of Louisiana at Lafayette University of Texas at San Antonio U.S.Army Engineer Research and Development Center (ERDC)

Coastal Louisiana has the nation’s most fragile and valuable wetlands,whose loss represents 80% of the total losses in the United *** severely restricted mobility of conventional shoreline protection structures makes them impossible to be *** Wave Suppression and sediment Collection(WSSC) system is a novel technology of high mobility and compatible with existing shoreline protection *** laboratory studies on WSSC showed great potential for wave reduction and sediment *** current study aimed to optimize the design parameters of WSSC using a validated computational model.A computational fluid dynamics (CFD) model was developed and validated using experimental data from the previous laboratory ***,a parametric analysis was conducted with a focus on the performance optimization of wave reduction and sediment collection with respect to pipe diameter and face *** results showed that the wave reduction efficiency decreased with increasing pipe diameter and face *** contrast,the sediment transport efficiency was enhanced by increasing pipe diameter but was not affected significantly by varying face slopes.

关键词： Breakwaters Computational fluid dynamics sediment transport Shoreline protection Coastal engineering ANSYS FLUENT

sediment transport in ice-covered channels

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International Journal of sediment Research 2015年第1期30卷 63-67页

作者： Ian KNACK Hung-tao SHEN Department of Civil and Environmental Engineering Clarkson University

The existence of ice cover has important effects on sediment transport and channel morphology for rivers in areas with an annual occurrence of an ice *** interaction of sediment transport and surface ice is poorly *** this paper,data from existing flume experiments,each with a limited range of flow and sediment transport conditions,are *** analysis showed that the bed load transport in ice-covered channels can be described by conventional relationships for the equivalent free-surface flow if the flow strength is expressed in terms of the bed shear stress.A modified Rouse formulation considering the effect of the ice cover on velocity and turbulent diffusion is shown to be applicable for calculating the suspended sediment transport discharge.

关键词： sediment transport Bed load Ice-covered channel Suspended load

sediment transport CAPACITY-AN IMPROVED BAGNOLD FORMULA

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International Journal of sediment Research 2007年第1期22卷 27-38页

作者： Sung-Cheol KOH In-Soo KIM Young-Chae SONG

This paper re-examines Bagnold’s theorem of sediment transport. Different from the stream power defined by Bagnold, i.e., τoV, this study shows that the total load of sediment-laden flow, gt, is related to near bed energy dissipation rate, i.e., τou*’. An attempt is made to explain the empirical relation. The ratio (=k) of measured total load, gt, to the product of near bed velocity, u*’, and energy dissipation rate, τou*’, is analyzed. It is found that k is independent of the Rouse number, Z, if Z is greater than 2.6, but the coefficient k decreases with the increase of Z when Z < 2.6. An empirical relation between k and Z is developed. A systematic and thorough analysis of 1,458 sets of data collected from 16 rivers and canals confirms that the proposed formula can be used to compute the total load with accuracy.

关键词： sediment transport River flow Total sediment discharge Stream power

Numerical modeling of sediment transport based on unsteady and steady flows by incompressible smoothed particle hydrodynamics method

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Journal of Hydrodynamics 2018年第5期30卷 928-942页

作者： Rasoul Memarzadeh Gholamabbas Barani Mahnaz Ghaeini-Hessaroeyeh Department of Civil Engineering Faculty of Engineering Shahid Bahonar University of Kerman Department of Civil Engineering Faculty of Engineering Vali-e-Asr University of Rafsanjan

The purpose of the present paper is to introduce a simple two-part multi-phase model for the sediment transport problems based on the incompressible smoothed particle hydrodynamics（ISPH） method. The proposed model simulates the movement of sediment particles in two parts. The sediment particles are classified into three categories, including the motionless particles, moving particles behave like a rigid body, and moving particles with a pseudo fluid behavior. The criterion for the classification of sediment particles is the Bingham rheological model. Verification of the present model is performed by simulation of the dam break waves on movable beds with different conditions and the bed scouring under steady flow condition. Comparison of the present model results, the experimental data and available numerical results show that it has good ability to simulate flow pattern and sediment transport.

关键词： sediment transport Bingham model dam break incompressible smoothed particle hydrodynamics (ISPH) method steady and unsteady flows two-part multi-phase model

Flow dynamics and sediment transport in vegetated rivers:A review

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Journal of Hydrodynamics 2021年第3期33卷 400-420页

作者： Wen-xin Huai Shuolin Li Gabriel G.Katul Meng-yang Liu Zhong-hua Yang State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan UniversityWuhan430072China Department of Civil and Environmental Engineering Duke UniversityDurhamNCUSA Nicholas School of the Environment and Earth Science Duke UniversityDurhamNCUSA

The significance of riparian vegetation on river flow and material transport is not in *** laws,sediment erosion and deposition,and element cycling must all be adjusted from their canonical rough-wall boundary layer to accommodate the presence of aquatic *** turn,the growth and colonization of riparian vegetation are affected by fluvial processes and river morphology on longer time *** interactions and feedbacks at multiple time scales are now drawing significant attention within the research community given their relevance to river *** this reason,a review summarizing methods,general laws,qualitative cognition,and quantitative models regarding the interplay between aquatic plants,flow dynamics,and sediment transport in vegetated rivers is in ***,pitfalls,knowledge gaps,and daunting challenges to the current state of knowledge are also *** a multidisciplinary research topic,a future research agenda and opportunities pertinent to river management and enhancement of ecosystem services are also highlighted.

关键词： Canopy flow river morphology riparian vegetation sediment transport

Coupling mechanism of mathematical models for sediment transport based on characteristic theory

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Science China(Technological Sciences) 2016年第11期59卷 1696-1706页

作者： DING Yun LI ZuiSen ZHONG DeYu KANG YanPing State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai University Nanjing 210098 China Zhejiang Institute of Hydraulics and Estuary Hangzhou 310008 China State Key Laboratory of Hydroscience and Engineering Tsinghua University Beijing 100084 China Jiangsu Hydraulic Research Institute Nanjing 210017 China

This paper aims to explore the coupling mechanism between flow movement, sediment transport and riverbed evolution in currently widely used mathematical models for sediment transport. Based on characteristic theory, analytic forms of eigenvalues,eigenvectors and characteristic relationships of total-sediment transport model, bed-load transport model and suspenedload transport model were derived, respectively. The singular perturbation technology was implemented to obtain the asymptotic solutions to different families of eigenvalues. The results indicate that, interactions between motion variables were explicitly coupled in the characteristics of total-sediment transport model and bed-load transport model. Further qualitative and quantitative analysis demonstrates that high sediment transport intensity and significant riverbed change will inevitably affect the property of flow movement. In the process of deposition, sediment-laden flow will move faster when sediment transport intensity becomes stronger. In contrast, the wave of flow will propagate at slower speed as erosion intensity becomes *** most existing suspended-load transport models, however, the characteristics are decoupled as the interactions between motion variables cannot be integrally illustrated in eigenvalues, eigenvectors and characteristic relationship.

关键词： coupling mechanism mathematical models sediment transport characteristics eigenvalues

Hydrodynamic Characteristics and sediment transport of A Tidal River Under Influence of Wading Engineering Groups

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China Ocean Engineering 2013年第6期27卷 829-842页

作者：陈珺唐洪武肖洋嵇敏 State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai University National Engineering Research Center of Water Resources Efficient Utilization and Engineering Safety Hohai University College of Dayu Hohai University

By taking the Yong River for example in this paper, based on the multiple measured data during 1957 to 2009, the change process of runoff, tide feature, tidal wave, tidal influx and sediment transport are analyzed. Then a mathematical model is used to reveal the influence mechanism on hydrodynamic characteristics and sediment transport of the wading engineering groups such as a tide gate, a breakwater, reservoirs, bridges and wharves, which were built in different periods. The results showed the hydrodynamic characteristics and sediment transport of the Yong River changed obviously due to the wading engineering groups. The tide gate induced deformation of the tidal wave, obvious reduction of the tidal influx and weakness of the tidal dynamic, decrease of the sediment yield of flood and ebb tide and channel deposition. The breakwater blocked estuarine entrances, resulting in the change of the tidal current and the reduction of the tidal influx in the estuarine area. The large-scale reservoirs gradually made the decrease of the Yong River runoff. The bridge and wharf groups took up cross-section areas, the cumulative affection of which caused the increase of tidal level in the tidal river.

关键词： hydrodynamic characteristics sediment transport wading engineering groups tidal river tide gate

sediment transport Investigation in the Yangtze Estuary with Radioactive Tracer

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China Ocean Engineering 1992年第4期7卷 471-482页

作者： Li Zhangsu Senior Engineer, Nanjing Hydraulic Research Institute, 210029, Nanjing

This paper describes a radioactive tracer experiment carried out at the landward spoil site of the North Passage in the Yangtze Estuary in June, 1991. Scandium -46 was selected as the tracer, the total activity released was 179.45 GBq and the amount of the Sandium-46 glass was 495 g. The purpose of the experiment was to determine the sediment movement direction, path, velocity and transport rate, and therefore, to provide direct evidence for using the landward spoil site in the future. The experimental results showed that the sediment movement was governed by the ebb tide current during the period of mean and neap tides when the radioactive tracer was injected both on the flood and ebb tides, and the sediment moved from the release point to the middle of the North Passage near navigation buoy No. 269. The direciton of the sediment movement was 110 ° , the particle velocity was 758 m/d, and the sediment transport rate per unit width was 47.8 m3 / md.

关键词： radioactive tracer sediment transport estuary injection centroid mobile layer thickness