Download or read book Boundary Conditions for Time Dependent Problems with an Artificial Boundary written by Bertil Gustafsson and published by . This book was released on 1977 with total page 56 pages. Available in PDF, EPUB and Kindle. Book excerpt: Many physical problems require the solution of partial differential equations on some infinite domain Omega with boundary del Omega. For computational reasons Omega is replaced by a finite domain Omega sub 1. The problem arises to specify boundary conditions at the artificial boundary B sub 2 and this paper discusses special techniques.

Download or read book Global discrete artificial boundary conditions for timedependent wave propagation written by and published by DIANE Publishing. This book was released on with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Artificial Boundary Method written by Houde Han and published by Springer Science & Business Media. This book was released on 2013-04-13 with total page 434 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Artificial Boundary Method" systematically introduces the artificial boundary method for the numerical solutions of partial differential equations in unbounded domains. Detailed discussions treat different types of problems, including Laplace, Helmholtz, heat, Schrödinger, and Navier and Stokes equations. Both numerical methods and error analysis are discussed. The book is intended for researchers working in the fields of computational mathematics and mechanical engineering. Prof. Houde Han works at Tsinghua University, China; Prof. Xiaonan Wu works at Hong Kong Baptist University, China.

Download or read book Global Discrete Artificial Boundary Conditions for Time dependent Wave Propagation written by Victor S. Ryabenkii and published by DIANE Publishing. This book was released on 2001 with total page 42 pages. Available in PDF, EPUB and Kindle. Book excerpt: We construct global artificial boundary conditions (ABCs) for the numerical simulation of wave processes on unbounded domains using a special non-deteriorating algorithm that has been developed previously for the long-term computation of wave-radiation solutions. The ABCs are obtained directly for the discrete formulation of the problem; in so doing, neither a rational approximation of 'non-reflecting kernels', nor discretization of the continuous boundary conditions is required. The extent of temporal nonlocality of the new ABCs appears fixed and limited; in addition, the ABCs can handle artificial boundaries of irregular shape on regular grids with no fitting/adaptation needed and no accuracy loss induced. The non-deteriorating algorithm, which is the core of the new ABCs, is inherently three-dimensional, it guarantees temporally uniform grid convergence of the solution driven by a continuously operating source on arbitrarily long time intervals, and provides unimprovable linear computational complexity with respect to the grid dimension. The algorithm is based on the presence of lacunae, i.e., aft fronts of the waves, in wave-type solutions in odd-dimension spaces. It can, in fact, be built as a modification on top of any consistent and stable finite-difference scheme, making its grid convergence uniform in time and at the same time keeping the rate of convergence the same as that of the non-modified scheme. In the paper, we delineate the construction of the global lacunae-based ABCs in the framework of a discretized wave equation. The ABCs are obtained for the most general formulation of the problem that involves radiation of waves by moving sources (e.g., radiation of acoustic waves by a maneuvering aircraft). We also present systematic numerical results that corroborate the theoretical design properties of the ABCs' algorithm.

Download or read book Artificial Boundary Conditions Based on the Difference Potentials Method written by and published by . This book was released on 1996 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Far Field Boundary Conditions for Time dependent Hyperbolic Systems written by Stanford University. Center for Large Scale Scientific Computation and published by . This book was released on 1987 with total page 19 pages. Available in PDF, EPUB and Kindle. Book excerpt: For problems defined on infinite domains, the most common computational methods use an artificial boundary gamma in order to make the computation finite. Since data are usually not available at this boundary, conditions must be used that somehow are related to the behavior of the solution outside the computational domain omega. This means that some apriori knowledge of the solution is necessary. In particular, if the system of differential equations has variable coefficients or is non-linear, then we shall make the coefficients constant outside omega. In this way there is a possibility to compute the solution exactly, or to compute it approximately in a simple way outside omega, such that boundary conditions can be derived on gamma. A previous work in the basic principles concerning artificial boundaries for hyperbolic systems were discussed. The one-dimensional case was analyzed thoroughly, and it was shown under what conditions it is possible to derive accurate conditions at the artificial boundary. A two-dimensional example was also treated, and a method leading to exact conditions for steady state solutions was presented. This paper at treats hyperbolic systems in two space-dimensions with non-zero initial data also outside omega.

Download or read book Topics in Computational Wave Propagation written by Mark Ainsworth and published by Springer. This book was released on 2011-09-27 with total page 410 pages. Available in PDF, EPUB and Kindle. Book excerpt: These ten detailed and authoritative survey articles on numerical methods for direct and inverse wave propagation problems are written by leading experts. Researchers and practitioners in computational wave propagation, from postgraduate level onwards, will find the breadth and depth of coverage of recent developments a valuable resource. The articles describe a wide range of topics on the application and analysis of methods for time and frequency domain PDE and boundary integral formulations of wave propagation problems. Electromagnetic, seismic and acoustic equations are considered. Recent developments in methods and analysis ranging from finite differences to hp-adaptive finite elements, including high-accuracy and fast methods are described with extensive references.

Download or read book Nonreflecting Boundary Conditions for Finite Element Methods Based Upon Off surface Boundary Integral Equations written by Ata Muğan and published by . This book was released on 1995 with total page 360 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Direct and Inverse Problems in Wave Propagation and Applications written by Ivan Graham and published by Walter de Gruyter. This book was released on 2013-10-14 with total page 328 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is the third volume of three volume series recording the "Radon Special Semester 2011 on Multiscale Simulation & Analysis in Energy and the Environment" taking place in Linz, Austria, October 3-7, 2011. This book surveys recent developments in the analysis of wave propagation problems. The topics covered include aspects of the forward problem and problems in inverse problems, as well as applications in the earth sciences. Wave propagation problems are ubiquitous in environmental applications such as seismic analysis, acoustic and electromagnetic scattering. The design of efficient numerical methods for the forward problem, in which the scattered field is computed from known geometric configurations is very challenging due to the multiscale nature of the problems. Even more challenging are inverse problems where material parameters and configurations have to be determined from measurements in conjunction with the forward problem. This book contains review articles covering several state-of-the-art numerical methods for both forward and inverse problems. This collection of survey articles focusses on the efficient computation of wave propagation and scattering is a core problem in numerical mathematics, which is currently of great research interest and is central to many applications in energy and the environment. Two generic applications which resonate strongly with the central aims of the Radon Special Semester 2011 are forward wave propagation in heterogeneous media and seismic inversion for subsurface imaging. As an example of the first application, modelling of absorption and scattering of radiation by clouds, aerosol and precipitation is used as a tool for interpretation of (e.g.) solar, infrared and radar measurements, and as a component in larger weather/climate prediction models in numerical weather forecasting. As an example of the second application, inverse problems in wave propagation in heterogeneous media arise in the problem of imaging the subsurface below land or marine deposits. The book records the achievements of Workshop 3 "Wave Propagation and Scattering, Inverse Problems and Applications in Energy and the Environment". It brings together key numerical mathematicians whose interest is in the analysis and computation of wave propagation and scattering problems, and in inverse problems, together with practitioners from engineering and industry whose interest is in the applications of these core problems.

Download or read book Exact Artificial Boundary Conditions for Problems with Period Structure written by Matthias Ehrhardt and published by . This book was released on 2008 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Numerical Methods for Problems in Infinite Domains written by D. Givoli and published by Elsevier. This book was released on 2013-10-22 with total page 316 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume reviews and discusses the main numerical methods used today for solving problems in infinite domains. It also presents in detail one very effective method in this class, namely the Dirichlet-to-Neumann (DtN) finite element method. The book is intended to provide the researcher or engineer with the state-of-the-art in numerical solution methods for infinite domain problems, such as the problems encountered in acoustics and structural acoustics, fluid dynamics, meteorology, and many other fields of application. The emphasis is on the fundamentals of the various methods, and on reporting recent progress and forecasting future directions. An appendix at the end of the book provides an introduction to the essentials of the finite element method, and suggests a short list of texts on the subject which are categorized by their level of mathematics.

Download or read book Acta Numerica 1999 Volume 8 written by Arieh Iserles and published by Cambridge University Press. This book was released on 1999-07-22 with total page 310 pages. Available in PDF, EPUB and Kindle. Book excerpt: Numerical analysis is the subject of applied mathematics concerned mainly with using computers in evaluating or approximating mathematical models. As such, it is crucial to all applications of mathematics in science and engineering, as well as being an important discipline on its own. Acta Numerica surveys annually the most important developments in numerical analysis and scientific computing. The subjects and authors of the substantive survey articles are chosen by a distinguished international editorial board so as to report the most important developments in the subject in a manner accessible to the wider community of professionals with an interest in scientific computing.

Download or read book Accurate Boundary Conditions for Exterior Problems in Gas Dynamics written by Thomas Hagstrom and published by . This book was released on 1988 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Absorbing Boundaries and Layers Domain Decomposition Methods written by L. Tourrette and published by Nova Publishers. This book was released on 2001 with total page 396 pages. Available in PDF, EPUB and Kindle. Book excerpt: CD-ROM contains: Sections omitted from printing of text.

Download or read book Third International Conference on Mathematical and Numerical Aspects of Wave Propagation written by Gary C. Cohen and published by SIAM. This book was released on 1995-01-01 with total page 830 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume contains the papers presented at the title conference. Speakers from 13 different countries were represented at the meeting. A broad range of topics in theoretical and applied wave propagation is covered.

Download or read book Computational Fluid and Solid Mechanics 2003 written by K.J Bathe and published by Elsevier. This book was released on 2003-06-02 with total page 2485 pages. Available in PDF, EPUB and Kindle. Book excerpt: Bringing together the world's leading researchers and practitioners of computational mechanics, these new volumes meet and build on the eight key challenges for research and development in computational mechanics. Researchers have recently identified eight critical research tasks facing the field of computational mechanics. These tasks have come about because it appears possible to reach a new level of mathematical modelling and numerical solution that will lead to a much deeper understanding of nature and to great improvements in engineering design.The eight tasks are: The automatic solution of mathematical models Effective numerical schemes for fluid flows The development of an effective mesh-free numerical solution method The development of numerical procedures for multiphysics problems The development of numerical procedures for multiscale problems The modelling of uncertainties The analysis of complete life cycles of systems Education - teaching sound engineering and scientific judgement Readers of Computational Fluid and Solid Mechanics 2003 will be able to apply the combined experience of many of the world's leading researchers to their own research needs. Those in academic environments will gain a better insight into the needs and constraints of the industries they are involved with; those in industry will gain a competitive advantage by gaining insight into the cutting edge research being carried out by colleagues in academia. Features Bridges the gap between academic researchers and practitioners in industry Outlines the eight main challenges facing Research and Design in Computational mechanics and offers new insights into the shifting the research agenda Provides a vision of how strong, basic and exciting education at university can be harmonized with life-long learning to obtain maximum value from the new powerful tools of analysis

Download or read book Geotechnical Hazards written by Z. Lisac and published by CRC Press. This book was released on 2020-12-17 with total page 907 pages. Available in PDF, EPUB and Kindle. Book excerpt: The contributions to this volume examine: geotechnical hazard acknowledging the deversity of local ground conditions and environmental factors which play a decisive role in designing engineering structures in Danubian countries.