Download or read book Numerical Simulation of the Coriolis Effect on Stratified Flow in an Estuary written by Monica Barbat and published by . This book was released on 1999 with total page 322 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Numerical Methods for Shallow Water Flow written by C.B. Vreugdenhil and published by Springer Science & Business Media. This book was released on 2013-03-09 with total page 273 pages. Available in PDF, EPUB and Kindle. Book excerpt: A wide variety of problems are associated with the flow of shallow water, such as atmospheric flows, tides, storm surges, river and coastal flows, lake flows, tsunamis. Numerical simulation is an effective tool in solving them and a great variety of numerical methods are available. The first part of the book summarizes the basic physics of shallow-water flow needed to use numerical methods under various conditions. The second part gives an overview of possible numerical methods, together with their stability and accuracy properties as well as with an assessment of their performance under various conditions. This enables the reader to select a method for particular applications. Correct treatment of boundary conditions (often neglected) is emphasized. The major part of the book is about two-dimensional shallow-water equations but a discussion of the 3-D form is included. The book is intended for researchers and users of shallow-water models in oceanographic and meteorological institutes, hydraulic engineering and consulting. It also provides a major source of information for applied and numerical mathematicians.
Download or read book Numerical Modelling of Stratified Flow in Estuaries written by Robert A. Laura and published by . This book was released on 1980 with total page 154 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Oceanic Abstracts written by and published by . This book was released on 1997-10 with total page 1070 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Contemporary Issues in Estuarine Physics written by Arnoldo Valle-Levinson and published by Cambridge University Press. This book was released on 2010-01-28 with total page 327 pages. Available in PDF, EPUB and Kindle. Book excerpt: Estuaries are of high socioeconomic importance with twenty-two of the thirty-two largest cities in the world located on river estuaries. Estuaries bring together fluxes of fresh and saline water, as well as fluvial and marine sediments, and contain high biological diversity. Increasingly sophisticated field observation technology and numerical modeling have produced significant advances in our understanding of the physical properties of estuaries over the last decade. This book introduces a classification for estuaries before presenting the basic physics and hydrodynamics of estuarine circulation and the various factors that modify it in time and space. It then covers special topics at the forefront of research such as turbulence, fronts in estuaries and continental shelves, low inflow estuaries, and implications of estuarine transport for water quality. Written by leading authorities on estuarine and lagoon hydrodynamics, this volume provides a concise foundation for academic researchers, advanced students and coastal resource managers.
Download or read book Numerical Modeling Of Ocean Dynamics written by Zygmunt Kowalik and published by World Scientific. This book was released on 1993-05-19 with total page 495 pages. Available in PDF, EPUB and Kindle. Book excerpt: While there are several excellent books dealing with numerical analysis and analytical theory, one has to practically sift through hundreds of references. This monograph is an attempt to partly rectify this situation. It aims to introduce the application of finite-difference methods to ocean dynamics as well as review other complex methods. Systematically presented, the monograph first gives a detailed account of the basics and then go on to discuss the various applications. Recognising the impossibility of covering the entire field of ocean dynamics, the writers have chosen to focus on transport equations (diffusion and advection), shallow water phenomena — tides, storm surges and tsunamis, three-dimensional time dependent oceanic motion, natural oscillations, and steady state phenomena. The many aspects covered by this book makes it an indispensable handbook and reference source to both professionals and students of this field.
Download or read book Selected Water Resources Abstracts written by and published by . This book was released on 1976 with total page 898 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book ASCE Combined Index written by American Society of Civil Engineers and published by . This book was released on 1990 with total page 860 pages. Available in PDF, EPUB and Kindle. Book excerpt: Indexes materials appearing in the Society's Journals, Transactions, Manuals and reports, Special publications, and Civil engineering.
Download or read book A Numerical Model for Stratified Flows in Estuaries and Reservoirs written by Patrick Sauvaget and published by . This book was released on 1985 with total page 354 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Dynamics of Stratified Flow Past a Sphere written by Anikesh Pal and published by . This book was released on 2016 with total page 170 pages. Available in PDF, EPUB and Kindle. Book excerpt: Wakes of bluff bodies in a stratified environment are common in oceanic and atmospheric flows. Some examples are marine swimmers, underwater submersibles and flow over mountains and islands. The first part of the research in stratified wakes concerns temporal/spatial simulations of turbulent self-propelled/towed wakes without including a body. Direct numerical simulations are performed to contrast the influence of the mean velocity profile with that of the initial turbulence on the subsequent evolution of velocity and density fluctuations in a stratified self-propelled wake. It is also verified that results of temporal simulations matches with that of the spatial simulations when the initial near-wake condition of the temporal approximation is chosen to match the inflow of the spatially evolving model. Typically, the wake of a body develops in the presence of external fluctuations, motivating a study of wake evolution under the influence of various intensities of external turbulence. The stratified wake was found to decay substantially faster than its unstratified counterpart for same intensity of the external turbulence. Theoretical arguments and additional simulations were performed to show that the level of external turbulence relative to wake turbulence is a key governing parameter in both stratified and unstratified backgrounds. The second part of this research focuses on flow past a sphere in a stratified fluid at a sub-critical Reynolds number of 3,700 and for a range of Froude numbers U/ND \in [0.025,1]. The conservation equations are solved in a cylindrical coordinate system and an immersed boundary method is employed to represent the sphere. The prime objective of this investigation is to understand the statistical response of the near, intermediate and far wake of a sphere at sub-critical Re under the influence of buoyancy. It is observed that buoyancy leads to the inhibition of vertical motion resulting in faster decay of r.m.s. velocity in the vertical direction as compared to the horizontal r.m.s. velocity, collapse of the wake, propagation of internal gravity waves and the organization of the primarily horizontal flow into coherent vortical structures. Unprecedented with respect to previous studies, the time averaged turbulent kinetic energy budget is closed for the unstratified and stratified cases. A novel finding of this research is the regeneration of turbulent fluctuations in the near wake when the stratification increases beyond a critical level (Fr decreases beyond a critical value) which is in contrast to the previous results at lower Re that suggest monotone suppression of turbulence with increasing stratification. Vorticity evolution, energy spectra and the turbulence energy equation explain turbulence regeneration. Another objective of this study is to quantify the distinction between the body and turbulence generated internal waves, in terms of the amplitude, frequency, potential energy distribution and propagation angles. With a decrease in Fr, the body generation mechanism become stronger and waves exhibit upstream propagation.
Download or read book Aquatic Sciences and Fisheries Abstracts written by and published by . This book was released on 1992 with total page 1460 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Numerical Simulations of the Stratified Oceanic Bottom Boundary Layer written by John Ryan Taylor and published by . This book was released on 2008 with total page 212 pages. Available in PDF, EPUB and Kindle. Book excerpt: Numerical simulations are used to consider several problems relevant to the turbulent oceanic bottom boundary layer. In the first study, stratified open channel flow is considered with thermal boundary conditions chosen to approximate a shallow sea. Specifically, a constant heat flux is applied at the free surface and the lower wall is assumed to be adiabatic. When the surface heat flux is strong, turbulent upwellings of low speed fluid from near the lower wall are inhibited by the stable stratification. Subsequent studies consider a stratified bottom Ekman layer over a non-sloping lower wall. The influence of the free surface is removed by using an open boundary condition at the top of the computational domain. Particular attention is paid to the influence of the outer layer stratification on the boundary layer structure. When the density field is initialized with a linear profile, a turbulent mixed layer forms near the wall, which is separated from the outer layer by a strongly stable pycnocline. It is found that the bottom stress is not strongly affected by the outer layer stratification. However, stratification reduces turbulent transport to the outer layer and strongly limits the boundary layer height. The mean shear at the top of the boundary layer is enhanced when the outer layer is stratified, and this shear is strong enough to cause intermittent instabilities above the pycnocline. Turbulence-generated internal gravity waves are observed in the outer layer with a relatively narrow frequency range. An explanation for frequency content of these waves is proposed, starting with an observed broad-banded turbulent spectrum and invoking linear viscous decay to explain the preferential damping of low and high frequency waves. During the course of this work, an open-source computational fluid dynamics code has been developed with a number of advanced features including scalar advection, subgrid-scale models for large-eddy simulation, and distributed memory parallelism.
Download or read book Oceanic Abstracts with Indexes written by and published by . This book was released on 1985 with total page 472 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Numerical Ocean Circulation Modeling written by Dale B. Haidvogel and published by World Scientific Publishing Company. This book was released on 1999 with total page 318 pages. Available in PDF, EPUB and Kindle. Book excerpt: "This book offers a comprehensive overview of the models and methods employed in the rapidly advancing field of numerical ocean circulation modeling. For those new to the field, concise reviews of the equations of oceanic motion, sub-grid-scale parameterization and numerical approximation techniques are presented. The extensive list of references make this book a valuable text for both graduate students and postdoctoral researchers in the marine sciences and in related fields, such as meteorology, climate and coupled biogeochemical modeling."--BOOK JACKET.Title Summary field provided by Blackwell North America, Inc. All Rights Reserved
Download or read book Multiscale Numerical Simulations of a Complex Macrotidal Tidal river Estuary written by Bing Wang and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Modern field-scale numerical models of estuaries have become widely used to study estuarine dynamics and to assess the impacts of engineering projects on estuaries. While current estuarine models focus primarily on the large-scale tidal dynamics, the model developed in the present study applies higher resolution than pre-existing models to capture the multiscale physics in a realistic estuary (the Snohomish River estuary). The scales range from tidally-driven variability in free surface, velocity and salinity in the estuary to the local-scale interaction of the tidal flow with an abrupt sill that has a dimension of roughly 10 m by 100 m. The model is developed using the SUNTANS solver and employs the Eulerian-Lagrangian Method (ELM) for advection of momentum for improved stability in the presence of substantial wetting and drying. The unstructured mesh extends more than 20 km to cover the advection of the salinity front, while the finest resolution applied around the sill is on the order of meters. Model predictions of free surface, currents and salinity are in good agreement with field measurements. Sensitivity analysis shows that the bathymetry of the intertidal mudflats across the bypass is critical for accurate prediction of the circulation around the sill, while bottom drag, advection of momentum, and fresh river inflow has a smaller and limited effect on the tidal flows. The performance of several two-equation turbulence closure models (k-kl, k-epsilon and k-omega) and stability functions (KC and CA) in predicting mixing and stratification is evaluated via the generic length scale (GLS) approach, and it shows small differences between the closure models. The model robustly obtains reasonable temporal and spatial mixing patterns in the estuary at different stages of a tidal cycle. A quadratic interpolation method is implemented for ELM following the framework in Walters et al. (2007), and both an idealized backward-facing step test case and field-scale simulations show improved accuracy and reduced diffusion and dissipation with the quadratic interpolation. When the quadratic interpolation is implemented with a fine mesh that incorporates 1 m resolution around the sill, the model captures the recirculating eddies downstream of the sill observed during ebb tides, and the velocity structures along a cross-channel transect close to the sill compare favorably to measurements. Finally, the highly variable local salinity field resulting from the interaction of the sill with the advection of the salinity front is discussed based on model results.
Download or read book Journal of Physical Oceanography written by and published by . This book was released on 2001-10 with total page 824 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Free Surface Flow Simulation in Estuarine and Coastal Environments written by Andrea Gilberto Filippini and published by . This book was released on 2016 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Over the last decades, there has been considerable attention in the accurate mathematical modeling and numerical simulations of free surface wave propagation in near-shore environments. A physical correct description of the large scale phenomena, which take place in the shallow water region, must account for strong nonlinear and dispersive effects, along with the interaction with complex topographies. First, a study on the behavior in nonlinear regime of different Boussinesq-type models is proposed, showing the advantage of using fully-nonlinear models with respect to weakly-nonlinear and weakly dispersive models (commonly employed). Secondly, a new flexible strategy for solving the fully-nonlinear and weakly-dispersive Green-Naghdi equations is presented, which allows to enhance an existing shallow water code by simply adding an algebraic term to the momentum balance and is particularly adapted for the use of hybrid techniques for wave breaking. Moreover, the first discretization of the Green-Naghdi equations on unstructured meshes is proposed via hybrid finite volume/ finite element schemes. Finally, the models and the methods developed in the thesis are deployed to study the physical problem of bore formation in convergent alluvial estuary, providing the first characterization of natural estuaries in terms of bore inception.
