Download or read book Non hydrostatic Models for Wave Propagation Breaking and Run up written by Zhangping Wei and published by . This book was released on 2014 with total page 136 pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation develops a series of non-hydrostatic pressure wave models based on the finite element free surface flow model, CCHE2D, for simulating propagation, breaking, and run-up of coastal wave processes. The first non-hydrostatic formulation presented in this dissertation directly introduces a non-hydrostatic pressure module into CCHE2D. An edge-based pressure allocation method is implemented, and a depth-integrated vertical momentum equation is introduced. The depth-integrated horizontal momentum equations are solved for a provisional velocity field, and then the non-hydrostatic pressure is obtained by satisfying the divergence-free velocity field condition, subsequently the velocity field is corrected by the non-hydrostatic pressure. Finally the free surface elevation is computed by the depth-integrated continuity equation. Next, a depth-integrated non-hydrostatic model for simulating nearshore wave processes is developed by solving a depth-integrated vertical momentum equation and the conservation form of the shallow water equations including extra non-hydrostatic pressure terms. A pressure projection method and the divergence-free velocity field condition are used together to solve the non-hydrostatic pressure. To resolve discontinuous flows, involving breaking waves and hydraulic jumps, a momentum conservation advection scheme is developed. In addition, the model is implemented with a simple but efficient wetting and drying algorithm to deal with the moving shoreline. The depth-integrated non-hydrostatic pressure models, which assume a linear distribution of the vertical pressure, have limitations in certain applications (e.g., propagation of highly dispersive waves). A multi-layer non-hydrostatic model is developed by adding more layers to the aforementioned second depth-integrated non-hydrostatic model. The multi-layer model is capable of resolving more realistic vertical flow structures and better representing the wave dynamics. Finally, a well validated depth-integrated non-hydrostatic model is applied to simulate a wide range of coastal wave processes. These numerical tests further evaluate the non-hydrostatic model from different aspects of engineering practice. In particular, they demonstrate the efficiency of non-hydrostatic models for coastal wave modeling, and they also reveal the great potential of non-hydrostatic models to simulate real-life coastal wave processes.
Download or read book Simulation of Water Waves by Boussinesq Models written by Ge Wei and published by . This book was released on 1997 with total page 234 pages. Available in PDF, EPUB and Kindle. Book excerpt: A new set of time-dependent Boussinesq equations is derived to simulate nonlinear long wave propagation in coastal regions. Following the approaches by Nwogu and later by Chen and Liu, the velocity (or velocity potential) at a certain water depth corresponding to the optimum linear dispersion property is used as a dependent variable. Therefore, the resulting equations are valid in intermediate water depth as well as for highly nonlinear waves. Coefficients for second order bound waves and the third order Schrodinger equation are derived and compared with exact solutions. A numerical model using a combination of second and fourth order schemes to discretize equation terms is developed for obtaining solutions to the equations. A fourth order predictor-corrector scheme is employed for time stepping and the first order derivative terms are finite differenced to fourth order accuracy, making the truncation errors smaller than the dispersive terms in the equations. Linear stability analysis is performed to determine the corresponding numerical stability range for the model. To avoid the problem of wave reflection from the conventional incident boundary condition, internal wave generation by source function is employed for the present model. Numerical filtering is applied at specified time steps in the model to eliminate short waves (about 2 to 5 times of the grid size) which are generated by the nonlinear interaction of long waves. To simulate the wave breaking process, additional terms for artificial eddy viscosity are included in the model equations to dissipate wave energy. The dissipation terms are activated when the horizontal gradient of the horizontal velocity exceeds the specified breaking criteria. Some of the existing models for simulating the process of wave runup are reviewed and we attempt to incorporate the present model to simulate the process by maintaining a thin layer of water over the physically dry grids.
Download or read book Dispersive Shallow Water Waves written by Gayaz Khakimzyanov and published by Springer Nature. This book was released on 2020-09-15 with total page 296 pages. Available in PDF, EPUB and Kindle. Book excerpt: This monograph presents cutting-edge research on dispersive wave modelling, and the numerical methods used to simulate the propagation and generation of long surface water waves. Including both an overview of existing dispersive models, as well as recent breakthroughs, the authors maintain an ideal balance between theory and applications. From modelling tsunami waves to smaller scale coastal processes, this book will be an indispensable resource for those looking to be brought up-to-date in this active area of scientific research. Beginning with an introduction to various dispersive long wave models on the flat space, the authors establish a foundation on which readers can confidently approach more advanced mathematical models and numerical techniques. The first two chapters of the book cover modelling and numerical simulation over globally flat spaces, including adaptive moving grid methods along with the operator splitting approach, which was historically proposed at the Institute of Computational Technologies at Novosibirsk. Later chapters build on this to explore high-end mathematical modelling of the fluid flow over deformed and rotating spheres using the operator splitting approach. The appendices that follow further elaborate by providing valuable insight into long wave models based on the potential flow assumption, and modified intermediate weakly nonlinear weakly dispersive equations. Dispersive Shallow Water Waves will be a valuable resource for researchers studying theoretical or applied oceanography, nonlinear waves as well as those more broadly interested in free surface flow dynamics.
Download or read book Non linear Wave Propagation written by Alan Jeffrey and published by . This book was released on 1964 with total page 388 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Wave Breaking written by Carlos M. Lemos and published by Springer Science & Business Media. This book was released on 2013-03-13 with total page 205 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this monograph, a finite difference algorithm for study- ing two dimensional wave breaking in the vertical plane is developed. The essential feature of this algorithm is the combination of the Volume-of-Fluid (VOF) technique for arbi- trary free surfaces and the k-E turbulence model. This me- thodology allows a self-contained study for wave transforma- tion processes in shallow water before, during and after breaking. This capability is illustrated in several calcula- tions. This book will be of interest for final year graduates, postgraduates and researchers working in the fields of tur- bulence modelling, wave hydrodynamics, coastal engineering, and oceanography of coastal regions.
Download or read book Model Equations for Wave Propagation from Deep to Shallow Water written by Philip L. F. Liu and published by . This book was released on 1993 with total page 80 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Hydrostatic and Non hydrostatic Internal Wave Models written by Bridget Marie Wadzuk and published by . This book was released on 2004 with total page 77 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Numerical Modeling of Wave Breaking Induced by Fixed Or Moving Boundaries written by and published by . This book was released on 1996 with total page 39 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this paper, several numerical aspects of an existing model for fully nonlinear waves are improved and validated to study wave breaking due to shoaling over a gentle plane slope and wave breaking induced by a moving lateral boundary. The model is based on fully nonlinear potential flow theory and combines a higher-order Boundary Element Method (BEM) for solving Laplace's equation at a given time and Lagrangian Taylor expansions for the time updating of the free surface position and potential. An improved numerical treatment of the boundary conditions at the intersection between moving lateral boundaries and the free surface (corner) is implemented and tested in the model, and the free surface interpolation method is also improved to better model highly curved regions of the free surface that occur in breaking waves. Finally, a node regridding technique is introduced to improve the resolution of the solution close to moving boundaries and in breaker jets. Examples are presented for solitary wave propagation, shoaling, and breaking over a 1:35 slope and for wave breaking induced by a moving vertical boundary. Using the new methods, both resolution and extent of computations are significantly improved compared to the earlier model, for similar computational efforts. In all cases computations can be carried out up to impact of the breaker jets on the free surface.
Download or read book Numerical of Ship Wave in River written by Nguyen Ba Thuy and published by . This book was released on 2017-06-06 with total page 84 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Feasibility of Modeling Run up Effects of Dispersive Water Waves written by J. M. Jordaan and published by . This book was released on 1965 with total page 84 pages. Available in PDF, EPUB and Kindle. Book excerpt: Studied were made in a laboratory test basin to determine the feasibility of modeling run-up effects of explosively generated water waves on beach and waterfront structures. Results were compared with (i) analytically derived predictions, and (ii) wave measurements (but not run-up) made in the ocean with high-energy (HE) explosives as the generating source. The test basin is 92 feet by 94 feet in size with 1:5, 1:13.6 and 1:5 sand beaches on three sides and on the fourth a 14-foot-diameter semi-paraboloidal plunger which by sudden plunge or retraction generates dispersive waves with dominant period of 2 seconds, height of 0.2 feet, and length of 20 feet in water 2-1/2 feet deep. It was found that wave motions are (i) predicted well by Green's Law, as modified for dispersive waves; and (ii) related to waves generated in the ocean by HE by the Froude scaling law. (Author).
Download or read book Non hydrostatic Modelling of Nearshore Wave Transformation and Breaking Over Varying Beach Morphology written by Esther Gomes and published by . This book was released on with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Review and Verification of Numerical Wave Models for Near Coastal Areas Part 1 Review of Mild Slope Equation Relevant Approximations and Technical Details of Numerical Wave Models written by and published by . This book was released on 1997 with total page 31 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ocean wave propagation is heavily affected by bathymetric variation, particularly in the nearshore areas. In this report, the theoretical basis behind the mild slope equation, which is often used for modeling wave propagation, is discussed. In particular, the theory and technical details of the models REF/DIF1, REF/DIF-S, and RCPWAVE are defined. (REF/DIF-S is an irregular wave version of REF/DIF1.) Two different modifications of the mild slope equation that simplify the modeling of wave propagation for general areas: the parabolic approximation, which is used in the model REF/DIF1 and REF/DIF-S; and the eikonal-transport equations, used in RCPWAVE are examined. The consequences of using either modification is also discussed. Incorporation of relevant physical effects (e.g., wave breaking, bottom friction, etc.) that affect wave propagation in the nearshore area is illustrated.
Download or read book A 2 D Boundary Integral Equation Model for Water Wave Generation Propagation and Run up written by Kuang-An Chang and published by . This book was released on 1994 with total page 224 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Boussinesq Modeling of Wave Transformation Breaking and Runup written by Andrew B. Kennedy and published by . This book was released on 1999 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Advanced Computational Methods in Science and Engineering written by Barry Koren and published by Springer Science & Business Media. This book was released on 2010-04-29 with total page 501 pages. Available in PDF, EPUB and Kindle. Book excerpt: The aim of the present book is to show, in a broad and yet deep way, the state of the art in computational science and engineering. Examples of topics addressed are: fast and accurate numerical algorithms, model-order reduction, grid computing, immersed-boundary methods, and specific computational methods for simulating a wide variety of challenging problems, problems such as: fluid-structure interaction, turbulent flames, bone-fracture healing, micro-electro-mechanical systems, failure of composite materials, storm surges, particulate flows, and so on. The main benefit offered to readers of the book is a well-balanced, up-to-date overview over the field of computational science and engineering, through in-depth articles by specialists from the separate disciplines.
Download or read book APAC 2019 written by Nguyen Trung Viet and published by Springer Nature. This book was released on 2019-09-25 with total page 1483 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents selected articles from the International Conference on Asian and Pacific Coasts (APAC 2019), an event intended to promote academic and technical exchange on coastal related studies, including coastal engineering and coastal environmental problems, among Asian and Pacific countries/regions. APAC is jointly supported by the Chinese Ocean Engineering Society (COES), the Coastal Engineering Committee of the Japan Society of Civil Engineers (JSCE), and the Korean Society of Coastal and Ocean Engineers (KSCOE). APAC is jointly supported by the Chinese Ocean Engineering Society (COES), the Coastal Engineering Committee of the Japan Society of Civil Engineers (JSCE), and the Korean Society of Coastal and Ocean Engineers (KSCOE).
Download or read book A Guide to Modeling Coastal Morphology written by Dano Roelvink and published by World Scientific. This book was released on 2012 with total page 291 pages. Available in PDF, EPUB and Kindle. Book excerpt: Process-based morphodynamic modelling is one of the relatively new tools at the disposal of coastal scientists, engineers and managers. On paper, it offers the possibility to analyse morphological processes and to investigate the effects of various measures one might consider to alleviate some problems. For these to be applied in practice, a model should be relatively straightforward to set up. It should be accurate enough to represent the details of interest, it should run long enough and robustly to see the real effects happen, and the physical processes represented in such a way that the sediment generally goes in the right direction at the right rate. Next, practitioners must be able to judge if the patterns and outcomes of the model are realistic and finally, translate these colour pictures and vector plots to integrated parameters that are relevant to the client or end user. In a nutshell, this book provides an in-depth review of ways to model coastal processes, including many hands-on exercises.
