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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

Ensemble and optimized hybrid algorithms through Runge Kutta optimizer for sewer sediment transport modeling using a data pre-processing approach

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International Journal of sediment Research 2023年第6期38卷 847-858页

作者： Enes Gul Mir Jafar Sadegh Safari Omer Faruk Dursun Gokmen Tayfur Department of Civil Engineering Inonu University Department of Civil Engineering Yasar University Department of Civil Engineering Izmir Institute of Technology

Uncontrolled sediment deposition in drainage and sewer systems raises unexpected maintenance *** this end,implementation of an accurate model relying on effective parameters involved is a reliable *** this study,three machine learning techniques,namely extreme learning machine(ELM),multilayer perceptron neural network(MLPNN),and M5P model tree(M5PMT);and three optimization approaches of Runge Kutta(RUN),genetic algorithm(GA),and particle swarm optimization(PSO) are applied for *** optimization and ensemble hybridization approaches are applied in the modeling *** the case of hybrid optimized models,the ELM and MLPNN models are hybridized with RUN,GA,and PSO algorithms to develop six hybrid models of ELM-RUN,ELM-GA,ELMPSO,MLPNN-RUN,MLPNN-GA,and *** hybrid models are developed through coupling the ELM and MLPNN models with the M5PMT *** data pre-processing approach is applied to find the best randomness characteristic of the utilized *** illustrate that the RUNbased hybrid models outperform the GA-and PSO-based *** the MLPNN-RUN and MLPNN-M5PMT hybrid models generate better results than their alternatives,MLPNN-M5PMT slightly outperforms MLPNN-RUN model with a coefficient of determination of 0.84 and a root mean square error of *** current study shows the superiority of the ensemble-based approach to the optimization *** investigation is needed by considering alternative optimization techniques to enhance sediment transport modeling.

关键词： Ensemble learning Hybrid model Machine learning Open channels sediment transport Sewer pipes

Experimental investigation of sediment transport in partially ice-covered channels

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International Journal of sediment Research 2023年第5期38卷 769-779页

作者： Mina Rouzegar Shawn P.Clark Department of Civil Engineering University of Manitoba

It is important to understand the effects of ice cover on sediment transport in cold climates, where subfreezing temperatures affect water bodies for a significant part of the year. The literature contains many studies on sediment transport in open channel flow, and several studies on sediment transport in completely ice-covered flow. There has been little or no research on sediment transport in partially icecovered channels. In the current study, laboratory experiments were done in a rectangular flume to quantify the impact of border ice presence on the sediment transport rate. The effects of ice cover extent and changing flow strengths on sediment transport distribution also were investigated, and the results were compared to those for fully ice-covered and open channel flow. The ice coverage ratios considered were 0(representing the open water condition), 0.25, 0.50, 0.67, and 1(representing fully ice-covered flow). The partial ice cover was found to impact the sediment transport distribution within the channel. The effect of ice coverage extent on sediment transport distribution was more significant at lower flow strengths and became negligible at higher flow strengths. The conventional equations for sediment transport in open channel flow and fully ice-covered flow that relate the dimensionless bedload transport rate to the flow strength were found to be applicable to estimate the total cross-section-averaged bedload transport for partially ice-covered flow when modified appropriately. Empirical coefficients for these equations were determined using the experimental data.

关键词： sediment transport Bedload Ice-covered channel Border ice

Developing a Lagrangian sediment transport model for open channel flows

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International Journal of sediment Research 2023年第2期38卷 153-165页

作者： Saman Baharvand Habib Ahmari Poorya Taghvaei Department of Civil Engineering The University of Texas at Arlington Department of Civil Engineering Semnan University

A three-dimensional stochastic Lagrangian particle tracking sediment transport model is developed to solve the discrete advection-dispersion equation using a combination of empirical dispersion *** performance of three widely-used longitudinal dispersion coefficient equations was examined to select one of them as the primary dispersion equation term in the developed model. Also, a conditional empirical equation was used to consider the effect of vertical dispersion term in top layers near the water surface. The performance of particle tracking model(PTM) to calculate the sediment concentration was evaluated for various sediment classes(very fine sand, fine sand, and medium sand) using available laboratory dataset. Multiple statistical measures were calculated using the Taylor diagram for each dispersion equation. Based on the result, the developed particle tracking model estimated the suspended sediment concentration in a rectangular open channel with a correlation coefficient(R) of 0.96, standard deviation(STD) of 0.262, and root mean square deviation(RMSD) of 0.06 for three different sediment classes proving the acceptable accuracy of the developed model for different range of sediment gradations. In addition, the accuracy of PTM was compared to recently developed models. Comparison between the particle tracking model and the analytical solution of the advection-dispersion equation showed that the developed model predicted the maximum concentration of suspended sediment 6% and9.4% lower than the analytical solution result for 30 and 50 s simulation time in the straight channel,respectively. However, there was a good agreement between the longitudinal and transverse sediment concentration distribution from the model and the analytical solution approach. The result of the sensitivity analysis and validation process showed that the model could be used to simulate sediment transport in open channel flows.

关键词： sediment transport Lagrangian particle tracking Stochastic approach Advection–dispersion Random walk

Numerical Simulation of Bed Load and Suspended Load sediment transport Using Well-Balanced Numerical Schemes

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Communications on Applied Mathematics and Computation 2023年第2期5卷 885-922页

作者： J.C.González-Aguirre J.A.González-Vázquez J.Alavez-Ramírez R.Silva M.E.Vázquez-Cendón División Acádemica de Ciencias Básicas Universidad Juárez Autónoma de TabascoCarr.Cunduacán-Jalpa de Mendéz KM.1CP 86690CunduacánTabascoMexico Universidad Autónoma Metropolitana-Unidad Iztapalapa Av.San Rafael Atlixco no.186Mexico CityMexico Instituto de Ingeniería Universidad Nacional Autónoma de México04510 Mexico CityMexico Departamento de Matemática Aplicada Universidade de Santiago de Compostela15706 Santiago de CompostelaSpain

sediment transport can be modelled using hydrodynamic models based on shallow water equations coupled with the sediment concentration conservation equation and the bed con-servation *** complete system of equations is made up of the energy balance law and the Exner *** numerical solution for this complete system is done in a seg-regated ***,the hyperbolic part of the system of balance laws is solved using a finite volume *** ways to compute the numerical flux have been considered,the Q-scheme of van Leer,the HLLCS approximate Riemann solver,and the last one takes into account the presence of non-conservative products in the *** discretisation of the source terms is carried out according to the numerical flux *** the second stage,the bed conservation equation is solved by using the approximation computed for the system of balance *** numerical schemes have been validated making comparisons between the obtained numerical results and the experimental data for some physical *** numerical results show a good agreement with the experimental data.

关键词： sediment transport Suspended load Bed load Finite volume method Numerical simulation Well-balanced schemes

A High-Order Conservative Semi-Lagrangian Solver for 3D Free Surface Flows with sediment transport on Voronoi Meshes

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Communications on Applied Mathematics and Computation 2023年第2期5卷 596-637页

作者： Matteo Bergami Walter Boscheri Giacomo Dimarco Department of Mathematics and Computer Science University of FerraraVia Machiavelli 30I-44121 FerraraItaly

In this paper,we present a conservative semi-Lagrangian scheme designed for the numeri-cal solution of 3D hydrostatic free surface flows involving sediment transport on unstruc-tured Voronoi meshes.A high-order reconstruction procedure is employed for obtaining a piecewise polynomial representation of the velocity field and sediment concentration within each control *** is subsequently exploited for the numerical integration of the Lagrangian trajectories needed for the discretization of the nonlinear convective and viscous *** presented method is fully conservative by construction,since the transported quantity or the vector field is integrated for each cell over the deformed vol-ume obtained at the foot of the characteristics that arises from all the vertexes defining the computational *** semi-Lagrangian approach allows the numerical scheme to be unconditionally stable for what concerns the advection part of the governing ***,a semi-implicit discretization permits to relax the time step restriction due to the acoustic impedance,hence yielding a stability condition which depends only on the explicit discretization of the viscous terms.A decoupled approach is then employed for the hydrostatic fluid solver and the transport of suspended sediment,which is assumed to be *** accuracy and the robustness of the resulting conservative semi-Lagrangian scheme are assessed through a suite of test cases and compared against the analytical solu-tion whenever is *** new numerical scheme can reach up to fourth order of accu-racy on general orthogonal meshes composed by Voronoi polygons.

关键词： Conservative semi-Lagrangian Free surface flows sediment transport High-order reconstruction Hydrostatic model

Assessing sediment transport dynamics from energy perspective by using the instrumented particle

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International Journal of sediment Research 2022年第6期37卷 833-846页

作者： Zaid Alhusban Manousos Valyrakis Institute for Environmental Sciences University of Koblenz-Landau School of Engineering University of Glasgow

sediment transport has been extensively studied. There is still a need to learn more about the mechanisms that make bed particles move, which is caused by turbulent flow in the low transport stages(above the motion threshold and below continuous transport). This work is focused on the use of an advanced tool to obtain a better perception of sediment transport dynamical methods: an instrumented particle equipped with a micro-electromechanical systems(MEMS) sensor. Particle transport experiments were carried out in a laboratory flume under a variety of well-controlled above-the-threshold-ofmotion flow conditions. By using sensor data, the kinetic energies were calculated with different flow rates and particle densities(mimicking different types of sediments sizes) to generate the probability distribution functions(PDFs) of particle transport features, like the total kinetic energy of particles,which provided information about particle interaction with the bed surface during its motion. The energy transfer efficiency was also studied, which can link the rate of energy transferred from the flow to the particle transport, so it can determine how efficiently a flow can transfer energy to the particle and how it affects the magnitude of sediment transport. In general, the instrumented particle response by a series of experiments showed consistent and satisfactory results and demonstrated its capability to record inertial dynamics because of flow turbulence at low cost. These experiments used different particle sizes and densities than those found in real-world sediments because of sensor size and lab *** do, however, provide a framework and trends that others can use to do more research into bed load transport rates in built canals and natural rivers.

关键词： River engineering sediment transport Micro-electromechanically sensors (MEMS) Kinetic energy analysis Flow rate Probability distribution function (PDF)

Coupled modeling of rainfall-induced floods and sediment transport at the catchment scale

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International Journal of sediment Research 2022年第6期37卷 715-728页

作者： Ronglan Huang Yufang Ni Zhixian Cao State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan University

Rainfall-induced floods may trigger intense sediment transport on erodible catchments, especially on the Loess Plateau in China, which in turn modifies the floods. However, the role of sediment transport in modifying floods has to date remained poorly understood. Concurrently, traditional hydrodynamic models for rainfall-induced floods typically ignore sediment transport, which may lead to inaccurate results for highly erodible catchments. Here, a two-dimensional(2 D) coupled shallow water hydro-sedimentmorphodynamic(SHSM) model, based on the Finite Volume Method on unstructured meshes and parallel computing, is proposed and applied to simulate rainfall-induced floods in the Zhidan catchment on the Loess Plateau, Shaanxi Province, China. For six historical floods of return periods up to 2 years, the numerical results compare well with observations of discharge hydrographs at the catchment outlet. The computed runoff-sediment yield relation is quantitatively reasonable as compared with other catchments under similar geographical conditions. It is revealed that neglecting sediment transport leads to underestimation of peak discharge of the flood by 14%-45%, whilst its effect on the timing of the peak discharge varies for different flood events. For 18 design floods with return periods of 10-500 years, sediment transport may lead to higher peak discharge by around 9%-15%. The temporal pattern of concentrated rainfall in a short period may lead to a larger exponent value of the power function for the runoff-sediment yield relation. The current finding leads us to propose that incorporating sediment transport in rainfallinduced flood modeling is warranted. The SHSM model is applicable to flood and sediment modeling at the catchment scale in support of risk management and water and soil management.

关键词： Catchment Floods Hydro-sediment-morphodynamic modeling sediment transport Soil erosion

sediment transport in Rivers with Overbank Flow

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四川大学学报（工程科学版） 2005年第S1期37卷 16-29页

作者： Donald W KNIGHT Water Eng. The Univ.of BirminghamUK

Some concepts related to sediment transport in rivers with overbank flow are *** a description of the physical processes that are involved when a river inundates its floodplains,some simple com- putational methods are presented which permit the depth-averaged velocity and boundary shear stress to be pre- dicted within a cross section of variable,but prismatic *** methoda account for the strong transverse shear in velocity that occurs when the stage is just above bankfull,as well as ...

关键词： sediment transport overbank flow

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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