Download or read book Hydrodynamic Modeling in Shallow Water with Wetting and Drying written by Justin Ross Davis and published by . This book was released on 1996 with total page 250 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Subgrid Approach for Unresolved Topography in Shallow Water Hydrodynamic Modeling written by Gihye Shin and published by . This book was released on 2016 with total page 376 pages. Available in PDF, EPUB and Kindle. Book excerpt: This study develops methods to represent the effect of subgrid scale topography for shallow water hydrodynamic models using Cartesian grids. Neglect of subgrid scale topographic variability is recognized as causing misrepresentation of wetting and drying processes (Defina, 2000). Subgrid topography has been previously parameterized at model-resolved grid scales using data from high-resolution digital elevation models to capture flow area and volume effects (e.g. Casulli, 2009), but proposed approaches have neglected key aspects of flow resistance. Form drag exerted by unresolved subgrid features cannot be arbitrarily neglected for shallow flow dynamics as it introduces complexity through directional variability. That is, the conventional approach to modeling subgrid frictional effects is through drag coefficients that apply identically to all flow directions through a grid cell; however, subgrid features can introduce directional bias through form drag, e.g. an embankment that blocks flow in only one direction. In the present work, two new model schemes were developed to address the frictional forcing on subgrid scale. These schemes are extensions of the subgrid modeling ideas of Volp et al. (2013) and Casulli (2009). The first new scheme is a subgrid drag model that determines directional drag coefficients representing the integrated and directionally-biased effects of subgrid drag. The second new scheme is a subgrid momentum model using the integrated fluxes through faces of a grid cell to represent subgrid forces and acceleration at the resolved-scale interface between two grid cells. The combination of these two methods is demonstrated to provide an approach to representing subgrid physical processes that have been missing in prior models. The new subgrid models were implemented in the Fine Resolution Environmental Hydrodynamics Model (Frehd) and validated using model-model comparisons at fine and coarse grid resolution. The validation test cases use real-world estuarine topography of a section from a 1×1 m lidar survey of the Nueces River Delta (Texas, USA). The new subgrid models are shown to reduce discrepancies between coarse-grid and fine-grid simulations over the time-space domain. Of key importance is that the new models can represent the flow deflection by subgrid topographic obstructions that cannot be captured without directional drag coefficients. This study indicates that application of the new subgrid modeling approaches can reduce grid-scale dependency that otherwise requires finer grid resolution to adequately capture flow physics.

Download or read book Shallow Water Hydrodynamics written by W.Y. Tan and published by Elsevier. This book was released on 1992-08-17 with total page 449 pages. Available in PDF, EPUB and Kindle. Book excerpt: Within this monograph a comprehensive and systematic knowledge on shallow-water hydrodynamics is presented. A two-dimensional system of shallow-water equations is analyzed, including the mathematical and mechanical backgrounds, the properties of the system and its solution. Also featured is a new mathematical simulation of shallow-water flows by compressible plane flows of a special virtual perfect gas, as well as practical algorithms such as FDM, FEM, and FVM. Some of these algorithms have been utilized in solving the system, while others have been utilized in various applied fields. An emphasis has been placed on several classes of high-performance difference schemes and boundary procedures which have found wide uses recently for solving the Euler equations of gas dynamics in aeronautical and aerospatial engineering. This book is constructed so that it may serve as a handbook for practicians. It will be of interest to scientists, designers, teachers, postgraduates and professionals in hydraulic, marine, and environmental engineering; especially those involved in the mathematical modelling of shallow-water bodies.

Download or read book Numerical Modelling of Hydrodynamics for Water Resources written by Pilar Garcia Navarro and published by CRC Press. This book was released on 2007-09-17 with total page 402 pages. Available in PDF, EPUB and Kindle. Book excerpt: Overland flow modelling has been an active field of research for some years, but developments in numerical methods and computational resources have recently accelerated progress, producing models for different geometries and types of flows, such as simulations of canal and river networks. Flow in canals has traditionally been described using

Download or read book Hydrodynamics and Water Quality written by Zhen-Gang Ji and published by John Wiley & Sons. This book was released on 2017-05-17 with total page 1153 pages. Available in PDF, EPUB and Kindle. Book excerpt: The primary reference for the modeling of hydrodynamics and water quality in rivers, lake, estuaries, coastal waters, and wetlands This comprehensive text perfectly illustrates the principles, basic processes, mathematical descriptions, case studies, and practical applications associated with surface waters. It focuses on solving practical problems in rivers, lakes, estuaries, coastal waters, and wetlands. Most of the theories and technical approaches presented within have been implemented in mathematical models and applied to solve practical problems. Throughout the book, case studies are presented to demonstrate how the basic theories and technical approaches are implemented into models, and how these models are applied to solve practical environmental/water resources problems. This new edition of Hydrodynamics and Water Quality: Modeling Rivers, Lakes, and Estuaries has been updated with more than 40% new information. It features several new chapters, including one devoted to shallow water processes in wetlands as well as another focused on extreme value theory and environmental risk analysis. It is also supplemented with a new website that provides files needed for sample applications, such as source codes, executable codes, input files, output files, model manuals, reports, technical notes, and utility programs. This new edition of the book: Includes more than 120 new/updated figures and 450 references Covers state-of-the-art hydrodynamics, sediment transport, toxics fate and transport, and water quality in surface waters Provides essential and updated information on mathematical models Focuses on how to solve practical problems in surface waters—presenting basic theories and technical approaches so that mathematical models can be understood and applied to simulate processes in surface waters Hailed as “a great addition to any university library” by the Journal of the American Water Resources Association (July 2009), Hydrodynamics and Water Quality, Second Edition is an essential reference for practicing engineers, scientists, and water resource managers worldwide.

Download or read book Numerical Modelling of Shallow Water Flows Over Mobile Beds written by Xin Liu and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This Ph.D. thesis aims to develop numerical models for two-dimensional and three-dimensional shallow water systems over mobile beds. In order to accomplish the goal of this dissertation, the following sub-projects are defined and completed. 1: The first sub-project consists in developing a robust two-dimensional coupled numerical model based on an unstructured mesh, which can simulate rapidly varying flows over an erodible bed involving wet-dry fronts that is a complex yet practically important problem. In this task, the central-upwind scheme is extended to simulation of bed erosion and sediment transport, a modified shallow water system is adopted to improve the model, a wetting and drying scheme is proposed for tracking wet-dry interfaces and stably predict the bed erosion near wet-dry area. The shallow water, sediment transport and bed evolution equations are coupled in the governing system. The proposed model can efficiently track wetting and drying interfaces while preserving stability in simulating the bed erosion near the wet-dry fronts. The additional terms in shallow water equations can improve the accuracy of the simulation when intense sediment-exchange exists; the central-upwind method adopted in the current study shows great accuracy and efficiency compared with other popular solvers; the developed model is robust, efficient and accurate in dealing with various challenging cases. 2: The second sub-project consists in developing a novel numerical scheme for a coupled two-dimensional hyperbolic system consisting of the shallow water equations with friction terms coupled with the equations modeling the sediment transport and bed evolution. The resulting 5*5 hyperbolic system of balance laws is numerically solved using a Godunov-type central-upwind scheme on a triangular grid. A spatially second-order and temporally third-order central-upwind scheme has been derived to discretize the conservative hyperbolic sub-system. However, such schemes need a correct evaluation of local wave speeds to avoid instabilities. To address such an issue, a mathematical result by the Lagrange theorem is used in the proposed scheme. Consequently, a computationally expensive process of finding all of the eigenvalues of the Jacobian matrices is avoided: The upper/lower bounds on the largest/smallest local speeds of propagation are estimated using the Lagrange theorem. In addition, a special discretization of the bed-slope term is proposed to guarantee the well-balanced property of the designed scheme. 3: The third sub-project consists in designing a novel scheme to estimate bed-load fluxes which can produce more accurate results than the previously reported coupled model. Using a pair of local wave speeds different from those used for the flow, a novel wave estimator in conjunction with the central upwind method is proposed and successfully applied to the coupled water-sediment system involving a rapid bed-erosion process. It was demonstrated that, in comparison with the decoupled model, applying the proposed novel scheme to approximate the bed-load fluxes can successfully avoid the numerical oscillations caused by simple and less stable schemes, e.g. simple upwind methods; in comparison with the coupled model using same flux-estimator for both hydrodynamic and morphological systems, the proposed numerical scheme successfully prevents excessive numerical diffusion for prediction of bed evolution. Consequently, the proposed scheme has advantages in terms of accuracy which are shown in several numerical tests. In addition, analytical expressions have been provided for calculating the eigenvalues of the coupled shallow-water-Exner system, which greatly enhances the efficiency of the proposed method. 4: The fourth sub-project consists in developing a three-dimensional numerical model for the simulation of unsteady non-hydrostatic shallow water flows on unstructured grids using the finite volume method. The free surface variations are modeled by a characteristics-based scheme which simulates sub- and super-critical flows. Three-dimensional velocity components are considered in a collocated arrangement with a sigma coordinate system. A special treatment of the pressure term is developed to avoid the water surface oscillations. Convective and diffusive terms are approximated explicitly, and an implicit discretization is used for the pressure term. The unstructured grid in the horizontal direction and the sigma coordinate in the vertical direction facilitate the use of the model in complicated geometries. 5: The fifth sub-project consists in developing a well-balanced three-dimensional shallow water model which is able to simulate shock waves over dry bed. Due to the hydrostatic simplification of the vertical momentum equation, the governing system of equations is not hyperbolic and can not be solved using standard hyperbolic solvers. That is, one can not use a high-order Godunov-type scheme to compute all fluxes through cell-interfaces. This may cause the model to fail in simulations of some unsteady-flows with discontinuities, e.g., dam-break flows and floods. To overcome this difficulty, a novel numerical scheme for the three-dimensional shallow water equations is proposed using a relaxation approach in order to convert the system to a hyperbolic one. Thus, a high-order Godunov-type central-upwind scheme based on the finite volume method can be applied to approximate the numerical fluxes. The proposed model can also preserve the ``lake at rest'' state and positivity of water depth over irregular bottom topographies based on special reconstruction of the corresponding parameters. 6: The sixth sub-project consists in extending the result of the fifth sub-project to development of a three-dimensional numerical model for shallow water flows over mobile beds, which is able to simulate morphological evolutions under shock waves, e.g. dam-break flows. The hydrodynamic model solves the three-dimensional shallow water equations using a finite volume method on prismatic cells in sigma coordinates based on the scheme prposed in sub-project 5. The morphodynamic model solves an Exner equation consisting of bed-load sediment transportation. The performance of the proposed model has been demonstrated by several laboratory experiments of dam-break flows over mobile beds.

Download or read book Modeling Shallow Water Flows Using the Discontinuous Galerkin Method written by Abdul A. Khan and published by CRC Press. This book was released on 2014-03-03 with total page 218 pages. Available in PDF, EPUB and Kindle. Book excerpt: Replacing the Traditional Physical Model Approach Computational models offer promise in improving the modeling of shallow water flows. As new techniques are considered, the process continues to change and evolve. Modeling Shallow Water Flows Using the Discontinuous Galerkin Method examines a technique that focuses on hyperbolic conservation laws and includes one-dimensional and two-dimensional shallow water flows and pollutant transports. Combines the Advantages of Finite Volume and Finite Element Methods This book explores the discontinuous Galerkin (DG) method, also known as the discontinuous finite element method, in depth. It introduces the DG method and its application to shallow water flows, as well as background information for implementing and applying this method for natural rivers. It considers dam-break problems, shock wave problems, and flows in different regimes (subcritical, supercritical, and transcritical). Readily Adaptable to the Real World While the DG method has been widely used in the fields of science and engineering, its use for hydraulics has so far been limited to simple cases. The book compares numerical results with laboratory experiments and field data, and includes a set of tests that can be used for a wide range of applications. Provides step-by-step implementation details Presents the different forms in which the shallow water flow equations can be written Places emphasis on the details and modifications required to apply the scheme to real-world flow problems This text enables readers to readily understand and develop an efficient computer simulation model that can be used to model flow, contaminant transport, and other aspects in rivers and coastal environments. It is an ideal resource for practicing environmental engineers and researchers in the area of computational hydraulics and fluid dynamics, and graduate students in computational hydraulics.

Download or read book The Mathematics of Marine Modelling written by Henk Schuttelaars and published by Springer Nature. This book was released on 2022-11-30 with total page 324 pages. Available in PDF, EPUB and Kindle. Book excerpt: Over the past few decades, numerical simulation has become instrumental in understanding the dynamics of seas, coastal regions and estuaries. The decision makers rely more and more frequently on model results for the management of these regions. Some modellers are insufficiently aware of the theoretical underpinning of the simulation tools they are using. On the other hand, a number of applied mathematicians tend to view marine sciences as a domain in which they would like to use the tools they have a good command of. Bridging the gap between model users and applied mathematicians is the main objective of the present book. In this respect a vast number of issues in which mathematics plays a crucial role will be addressed.

Download or read book Integrating Water Systems written by Joby Boxall and published by CRC Press. This book was released on 2009-07-24 with total page 834 pages. Available in PDF, EPUB and Kindle. Book excerpt: A collection of articles by leading international experts on modeling and control of potable water distribution and sewerage collection systems, focusing on advances in sensors, instrumentation and communications technologies; assessment of sensor reliability, accuracy and fitness; data management including SCADA and GIS; system

Download or read book Water Resources Management VI written by C. A. Brebbia and published by WIT Press. This book was released on 2011 with total page 865 pages. Available in PDF, EPUB and Kindle. Book excerpt: The biennial Water Resources Management conference is one of the most important of several water-related conferences organised by the Wessex Institute of Technology.As water becomes an increasingly precious resource, communities all over the world Are under extreme pressure to ensure its continued adequate supply to their populations. It is therefore essential that those responsible for managing water resources share their expertise in dealing with issues of water quality, quantity, management and planning, as well as other related concerns that help or hinder sustainable management of this vital resource. In this volume, containing research on recent technological and scientific developments associated with the management of surface and sub-surface water presented at the Sixth International Conference on Water Resources Management, they do just that. The research covers: Water management and planning; Waste water treatment, management, and re-use; Markets, policies and contracts; The right to water; Urban water management; Water quality; Pollution control; Irrigation problems; River basin management; Hydraulic engineering and Hydrological modelling; Flood risk; Decision support systems; Remediation and renaturalisation; Climate change and water resources; Governance and monitoring; Regional and geo-politics of water; Economics; Water ecology; Sanitation; Wetlands; and Extreme events.

Download or read book Implementation and Analysis of a New Wetting and Drying Framework for Generalized Wave Continuity Equation based Hydrodynamic Models written by Casey Gene Dick and published by . This book was released on 2011 with total page 222 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Hydrobiological Modelling written by Brian J. Williams and published by Lulu.com. This book was released on 2006 with total page 702 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book describes models of aquatic ecosystems, ranging from lakes to estuaries to the deep ocean. It provides a background in the physical and biological processes, numerical methods and elementary ecosystem models. It describes two of the most widely used hydrodynamic models and presents a number of case studies. The practice of modelling in management is discussed.

Download or read book Computational Fluid Dynamics written by Paul D. Bates and published by John Wiley & Sons. This book was released on 2005-08-05 with total page 540 pages. Available in PDF, EPUB and Kindle. Book excerpt: Uniquely outlines CFD theory in a manner relevant to environmental applications. This book addresses the basic topics in CFD modelling in a thematic manner to provided the necessary theoretical background, as well as providing global cases studies showing how CFD models can be used in practice demonstrating how good practice can be achieved , with reference to both established and new applications. First book to apply CFD to the environmental sciences Written at a level suitable for non-mathematicians

Download or read book River Basin Management VII written by C. A. Brebbia and published by WIT Press. This book was released on 2012-05-22 with total page 473 pages. Available in PDF, EPUB and Kindle. Book excerpt: Containing papers presented seventh international conference on the topic, this book Reviews the advances have been made in the development and application of software tools for predicting the flow, water quality, sediment transport and ecological processes in river systems. Organised by the Wessex Institute of Technology, the biennial conference was first held in 2001. The papers presented at the Conference address Water resources management; Flood risk management; Ecological and environmental impact; Erosion and sediment transport; Hydrological modelling; Sustainable rivers; Rivers and tourism; River restoration and rehabilitation; Hydropower impacts and solutions; River and watershed management; Integrated management; Water quality issues; Eutrophication and agricultural Pollution; Trans-boundary river issues; Estuaries, deltas and lagoons; Changing climate and adaptive water Management; Droughts and desertification; Wetlands; Water and health; Socio-economic and political issues; Water governance and water justice.

Download or read book Shock Capturing Methods for Free Surface Shallow Flows written by E. F. Toro and published by . This book was released on 2001-03-30 with total page 336 pages. Available in PDF, EPUB and Kindle. Book excerpt: The first of its kind in the field, this title examines the use of modern, shock-capturing finite volume numerical methods, in the solution of partial differential equations associated with free-surface flows, which satisfy the shallow-water type assumption (including shallow water flows, dense gases and mixtures of materials as special samples). Starting with a general presentation of the governing equations for free-surface shallow flows and a discussion of their physical applicability, the book goes on to analyse the mathematical properties of the equations, in preparation for the presentation of the exact solution of the Riemann problem for wet and dry beds. After a general introduction to the finite volume approach, several chapters are then devoted to describing a variety of modern shock-capturing finite volume numerical methods, including Godunov methods of the upwind and centred type. Approximate Riemann solvers following various approaches are studied in detail as is their use in the Godunov approach for constructing low and high-order upwind TVD methods. Centred TVD schemes are also presented. Two chapters are then devoted to practical applications. The book finishes with an overview of potential practical applications of the methods studied, along with appropriate reference to sources of further information. Features include: * Algorithmic and practical presentation of the methods * Practical applications such as dam-break modelling and the study of bore reflection patterns in two space dimensions * Sample computer programs and accompanying numerical software (details available at www.numeritek.com) The book is suitable for teaching postgraduate students of civil, mechanical, hydraulic and environmental engineering, meteorology, oceanography, fluid mechanics and applied mathematics. Selected portions of the material may also be useful in teaching final year undergraduate students in the above disciplines. The contents will also be of interest to research scientists and engineers in academia and research and consultancy laboratories.

Download or read book Coastal Wetlands written by Gerardo Perillo and published by Elsevier. This book was released on 2018-11-02 with total page 1130 pages. Available in PDF, EPUB and Kindle. Book excerpt: Coastal Wetlands, Second Edition: An Integrated and Ecosystem Approach provides an understanding of the functioning of coastal ecosystems and the ecological services that they provide. As coastal wetlands are under a great deal of pressure from the dual forces of rising sea levels and the intervention of human populations, both along the estuary and in the river catchment, this book covers important issues, such as the destruction or degradation of wetlands from land reclamation and infrastructures, impacts from the discharge of pollutants, changes in river flows and sediment supplies, land clearing, and dam operations. Covers climate change and its influence on coastal wetland form and function Provides a fully updated and expanded resource, including new chapters on modeling, management and the impact of climate change Contains full-color figures of wetlands and estuaries in different parts of the world

Download or read book Selected Papers from the 13th Estuarine and Coastal Modeling Conference written by Henry J. Bokuniewicz and published by MDPI. This book was released on 2018-10-02 with total page 434 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is a printed edition of the Special Issue "Selected Papers from the 13th Estuarine and Coastal Modeling Conference" that was published in JMSE