Download or read book Mathematical Modelling of Sediment Transport and Bed Transients in Multi channel River Networks Under Conditions of Unsteady Flow written by Brian Morse and published by . This book was released on 1991 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Mathematical Modelling of Sediment Transport and Bed Transients in Multi channel River Networks Under Conditions of Unsteady Flow written by Brian Morse and published by . This book was released on 1991 with total page 500 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Computational River Dynamics written by Weiming Wu and published by CRC Press. This book was released on 2007-11-15 with total page 509 pages. Available in PDF, EPUB and Kindle. Book excerpt: Comprehensive text on the fundamentals of modeling flow and sediment transport in rivers treating both physical principles and numerical methods for various degrees of complexity. Includes 1-D, 2-D (both depth- and width-averaged) and 3-D models, as well as the integration and coupling of these models. Contains a broad selection
Download or read book Canadian Journal of Civil Engineering written by and published by . This book was released on 1997 with total page 598 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Dissertation Abstracts International written by and published by . This book was released on 1992 with total page 742 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Stream Bank Stability written by Tsu-Yi Su and published by . This book was released on 1981 with total page 66 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Analysis and Modelling of River Meandering written by Alessandra Crosato and published by IOS Press. This book was released on 2008 with total page 272 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis examines the morphological changes of non-tidal meandering rivers at the spatial scale of several meanders. With this purpose, a physics-based mathematical model, MIANDRAS, has been developed for the simulation of the medium-term to long-term evolution of meandering rivers. Application to several real rivers shows that MIANDRAS can properly simulate both equilibrium river bed topography and planimetric changes. Three models of different complexity can be obtained by applying different degrees of simplification to the equations. These models, along with experimental tests and field data, constitute the tools for several analyses. At conditions of initiation of meandering, it is found that river bends can migrate upstream and downstream. This depends on meander wave length and width-to-depth ratio, irrespective of whether the parameters are in the subresonant or the superresonant range.
Download or read book Computational Methods in Surface Hydrology written by G. Gambolati and published by Springer. This book was released on 1990 with total page 584 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Mathematical Modeling of Sedimentation Effects on Water Resources Systems written by S. Y. Wang and published by . This book was released on 1986 with total page 88 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Coastal Estuarial and Harbour Engineer s Reference Book written by Michael B Abbott and published by CRC Press. This book was released on 1993-11-11 with total page 760 pages. Available in PDF, EPUB and Kindle. Book excerpt: A major new reference book bringing together wide-ranging expert guidance on coastal engineering, including harbours and estuaries. It covers both traditional engineering topics and the fast developing areas of mathematical modelling and computer simulation.
Download or read book Numerical Study of Sediment Transport Under Unsteady Flow written by Shiyan Zhang and published by . This book was released on 2011 with total page 380 pages. Available in PDF, EPUB and Kindle. Book excerpt: Numerical model for simulating sediment transport in unsteady flow is incomplete in several aspects: first of all, the numerical schemes have been proved suitable for the simulation of flow over rigid bed needs to be reevaluated for unsteady flow over mobile bed; secondly, existing non-equilibrium sediment transport models are empirically developed and therefore lack of consistency regarding the evaluation of the non-equilibrium parameters; thirdly, the sediment transport in various applications have unique features which needs to be considered in the models. Sediment transport in unsteady flows was studied using analytical and numerical methods. A one dimensional (1D) finite volume method (FVM) model was developed. Five popular numerical schemes were implemented into the model and their performances were evaluated under highly unsteady flow condition. A novel physically-based non-equilibrium sediment transport model was established to describe the non-equilibrium sediment transport process. Infiltration effects on flow and sediment transport was included to make the model applicable to simulate irrigation induced soil erosion in furrows. The Laursen (1958) formula was adopted and modified to calculate the erodibility of fine-grain sized soil, and then verified by laboratory and field datasets. The numerical model was applied to a series of simulations of sediment transport in highly unsteady flow including the dam break erosional flow, flash flood in natural rivers and irrigation flows and proved to be applicable in various applications. The first order schemes were able to produce smooth and reasonably accurate results, and spurious oscillations were observed in the simulated results produced by second order schemes. The proposed non-equilibrium sediment transport model yielded better results than several other models in the literatures. The modified Laursen (1958) formula adopted was applicable in calculating the erodibility of the soil in irrigation. Additionally, it was indicated that the effect of the jet erosion and the structural failure of the discontinuous bed topography cannot be properly accounted for due to the limitation of 1D model. The comparison between the simulated and measured sediment discharge hydrographs indicated a potential process associated to the transport of the fine-grain sized soil in the irrigation furrows.
Download or read book SUTRENCH model written by L. C. van Rijn and published by . This book was released on 1985 with total page 68 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Mathematical Model of Estuarial Sediment Transport written by Ranjan Ariathurai and published by . This book was released on 1977 with total page 174 pages. Available in PDF, EPUB and Kindle. Book excerpt: A two-dimensional finite element model that simulates erosion, Transport, and deposition of suspended sediments is presented. The breadth-averaged or depth-averaged equations may be used depending on the problem to be solved. The governing equations for two phase transport are derived and then solved by the finite element method using isoparametric quadrilateral elements in which a quadratic approximation is made for the suspended sediment concentrations. Expressions used for the rates and conditions under which erosion and deposition occur are from previous experimental studies. Continuing aggregation is accounted for by specifying the settling velocity of the flocs in each element at each time step. The bed is considered to be formed of a number of layers of sediment whose physical properties change with overburden pressure. The model provides suspended sediment concentrations and bed profile at each time step. Numerical stability and convergence tests were conducted by comparing simulated results with analytic solutions and actual measurements. The original model, SEDIMENT I, was verified by comparison with measurements in a recirculating flume. The modified model, SEDIMENT II, developed for this project was verified by comparison with field measurements in the Savannah Estuary, Georgia. (Author).
Download or read book An Approach to the Sediment Transport Problem from General Physics written by Ralph Alger Bagnold and published by . This book was released on 1966 with total page 48 pages. Available in PDF, EPUB and Kindle. Book excerpt: From considerations of energy balance and of mechanical equilibrium, a mathematical expression is derived relating the rates of sediment transport as bedload and as suspended load to the expenditure of power by a statistically steady flow of water.
Download or read book Three dimensional Numerical Simulation of Mobile bed Hydrodynamics written by Miodrag Spasojevic and published by . This book was released on 1993 with total page 172 pages. Available in PDF, EPUB and Kindle. Book excerpt: "This report describes the theoretical principles of three-dimensional sediment transport and bed-evolution processes, and numerical solution of the appropriate governing equations. It also includes technical documentation and user's instructions for the sediment-operations program module developed as an integral part of the CH3D code."--P. ii.
Download or read book Sedimentation and Sediment Transport written by A. Gyr and published by Springer Science & Business Media. This book was released on 2003-05-31 with total page 292 pages. Available in PDF, EPUB and Kindle. Book excerpt: It is evident, that for a number of ecological and technical problems in rivers and lakes a better knowledge of sediment transport and sedimentation is needed together with the ability to predict and simulate sediment behaviour. On the other hand, a stagnation of research in these topics could be observed in the last decades. At the Symposium an attempt was made to present new results in mathematics and natural sciences relevant for the sediment problem. New strategies were discussed to tackle the complexity of the problem. Basic theoretical research and laboratory experiments alone are incomplete without a feedback from field observations and measurements. For that reason well-known researchers from both basic and engineering sciences were invited. Turbulence, non-local phenomena, stability, interaction, feedback systems, self-organization, two-phase flow and chaotic processes, numerical simulations as well as measurement techniques and field results were the keywords of the Symposium. This proceedings are a good source for those interested in the state of the art.
Download or read book Simulating Surface Flow and Sediment Transport in Vegetated Watershed for Current and Future Climate Condition written by Yang Bai and published by . This book was released on 2014 with total page 126 pages. Available in PDF, EPUB and Kindle. Book excerpt: The complex interaction between flow, vegetation and sediment drives the never settled changes of riverine system. Vegetation intercepts rainfall, adds resistance to surface flow, and facilitates infiltration. The magnitude and timing of flood flow are closely related to the watershed vegetation coverage. In the meantime, flood flow can transport a large amount of sediment resulting in bank erosion, channel degradation, and channel pattern change. As climate changes, future flood frequency will change with more intense rainfalls. However, the quantitative simulation of flood flow in vegetated channel and the influence of climate change on flood frequency, especially for the arid and semi-arid Southwest, remain challenges to engineers and scientists. Therefore, this research consists of two main parts: simulate unsteady flow and sediment transport in vegetated channel network, and quantify the impacts of climate change on flood frequency. A one-dimensional model for simulating flood routing and sediment transport over mobile alluvium in a vegetated channel network was developed. The modified St. Venant equations together with the governing equations for suspended sediment and bed load transport were solved simultaneously to obtain flow properties and sediment transport rate. The Godunov-type finite volume method is employed to discretize the governing equations. Then, the Exner equation was solved for bed elevation change. Since sediment transport is non-equilibrium when bed is degrading or aggrading, a recovery coefficient for suspended sediment and an adaptation length for bed load transport were used to quantify the differences between equilibrium and non-equilibrium sediment transport rate. The influence of vegetation on floodplain and main channel was accounted for by adjusting resistance terms in the momentum equations for flow field. A procedure to separate the grain resistance from the total resistance was proposed and implemented to calculate sediment transport rate. The model was tested by a flume experiment case and an unprecedented flood event occurred in the Santa Cruz River, Tucson, Arizona, in July 2006. Simulated results of flow discharge and bed elevation changes showed satisfactory agreements with the measurements. The impacts of vegetation density on sediment transport and significance of non-equilibrium sediment transport model were accounted for by the model. The two-dimensional surface flow model, called CHRE2D, was improved by considering the vegetation influence and then applied to Santa Cruz River Watershed (SCRW) in the Southern Arizona. The parameters in the CHRE2D model were calibrated by using the rainfall event in July 15th, 1999. Hourly precipitation data from a Regional Climate Model (RCM) called Weather Research and Forecasting model (WRF), for three periods, 1990-2000, 2031-2040 and 2071-2079, were used to quantify the impact of climate change on the magnitude and frequency of flood for the Santa Cruz River Watershed (SCRW) in the Southern Arizona. Precipitation outputs from RCM-WRF model were bias-corrected using observed gridded precipitation data for three periods before directly used in the watershed model. The watershed model was calibrated using the rainfall event in July 15th, 1999. The calibrated watershed model was applied to SCRW to simulate surface flow routing for the selected three periods. Simulated annual and daily maximum discharges are analyzed to obtain future flood frequency curves. Results indicate that flood discharges for different return periods are increased: the discharges of 100-year and 200-year return period are increased by 3,000 and 5,000 cfs, respectively.
