Download or read book An Adaptive Mesh Refinement Algorithm for the Discrete Ordinates Method written by and published by . This book was released on 1996 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Discrete Ordinates Algorithm for Radiation Transport Using Block Structured Adaptive Mesh Refinement written by L. H. Howell and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The discrete ordinates method is well-suited to implementation with block-structured adaptive mesh refinement (AMR). AMR meshes group points into logically-rectangular patches, and provide the benefits of adaptivity without sacrificing the efficiency and geometric regularity of regular grids. In particular, these meshes preserve the directional ordering of points required for explicit ordinate transport sweeps. A number of algorithmic issues must be addressed to make such a method practical. These include sequencing of ordinates and grids for parallel execution, simultaneous solution of the transport equation on multiple levels of the grid hierarchy, implicit coupling to the fluid energy, and conservation of energy in a time-dependent context where different grid levels advance with different timesteps. The author discusses these and other issues and present example calculations in two and three spatial dimensions.
Download or read book Adaptive Mesh Refinement Theory and Applications written by Tomasz Plewa and published by Springer Science & Business Media. This book was released on 2005-12-20 with total page 550 pages. Available in PDF, EPUB and Kindle. Book excerpt: Advanced numerical simulations that use adaptive mesh refinement (AMR) methods have now become routine in engineering and science. Originally developed for computational fluid dynamics applications these methods have propagated to fields as diverse as astrophysics, climate modeling, combustion, biophysics and many others. The underlying physical models and equations used in these disciplines are rather different, yet algorithmic and implementation issues facing practitioners are often remarkably similar. Unfortunately, there has been little effort to review the advances and outstanding issues of adaptive mesh refinement methods across such a variety of fields. This book attempts to bridge this gap. The book presents a collection of papers by experts in the field of AMR who analyze past advances in the field and evaluate the current state of adaptive mesh refinement methods in scientific computing.
Download or read book Object Oriented Methods for Interoperable Scientific and Engineering Computing written by Michael E. Henderson and published by SIAM. This book was released on 1999-01-01 with total page 340 pages. Available in PDF, EPUB and Kindle. Book excerpt: Contains papers presented at the October 1998 SIAM Workshop on Object Oriented Methods for Interoperable Scientific and Engineering Computing that covered a variety of topics and issues related to designing and implementing computational tools for science and engineering.
Download or read book A 3 D Adaptive Mesh Refinement Algorithm for Multimaterial Gas Dynamics written by and published by . This book was released on 1991 with total page 18 pages. Available in PDF, EPUB and Kindle. Book excerpt: Adaptive Mesh Refinement (AMR) in conjunction with high order upwind finite difference methods has been used effectively on a variety of problems. In this paper we discuss an implementation of an AMR finite difference method that solves the equations of gas dynamics with two material species in three dimensions. An equation for the evolution of volume fractions augments the gas dynamics system. The material interface is preserved and tracked from the volume fractions using a piecewise linear reconstruction technique. 14 refs., 4 figs.
Download or read book Adaptive Mesh Methods and Software for Time dependent Partial Differential Equations written by Shengtai Li and published by . This book was released on 1998 with total page 574 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Radiative Heat Transfer written by Michael F. Modest and published by Academic Press. This book was released on 2021-10-16 with total page 1018 pages. Available in PDF, EPUB and Kindle. Book excerpt: Radiative Heat Transfer, Fourth Edition is a fully updated, revised and practical reference on the basic physics and computational tools scientists and researchers use to solve problems in the broad field of radiative heat transfer. This book is acknowledged as the core reference in the field, providing models, methodologies and calculations essential to solving research problems. It is applicable to a variety of industries, including nuclear, solar and combustion energy, aerospace, chemical and materials processing, as well as environmental, biomedical and nanotechnology fields. Contemporary examples and problems surrounding sustainable energy, materials and process engineering are an essential addition to this edition. Includes end-of-chapter problems and a solutions manual, providing a structured and coherent reference Presents many worked examples which have been brought fully up-to-date to reflect the latest research Details many computer codes, ranging from basic problem solving aids to sophisticated research tools
Download or read book A Parallel Adaptive Mesh Refinement Algorithm written by James J. Quirk and published by . This book was released on 1993 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Journal of Thermophysics and Heat Transfer written by and published by . This book was released on 1997 with total page 642 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Nuclear Computational Science written by Yousry Azmy and published by Springer Science & Business Media. This book was released on 2010-04-15 with total page 476 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nuclear engineering has undergone extensive progress over the years. In the past century, colossal developments have been made and with specific reference to the mathematical theory and computational science underlying this discipline, advances in areas such as high-order discretization methods, Krylov Methods and Iteration Acceleration have steadily grown. Nuclear Computational Science: A Century in Review addresses these topics and many more; topics which hold special ties to the first half of the century, and topics focused around the unique combination of nuclear engineering, computational science and mathematical theory. Comprising eight chapters, Nuclear Computational Science: A Century in Review incorporates a number of carefully selected issues representing a variety of problems, providing the reader with a wealth of information in both a clear and concise manner. The comprehensive nature of the coverage and the stature of the contributing authors combine to make this a unique landmark publication. Targeting the medium to advanced level academic, this book will appeal to researchers and students with an interest in the progression of mathematical theory and its application to nuclear computational science.
Download or read book Issues in Energy Conversion Transmission and Systems 2011 Edition written by and published by ScholarlyEditions. This book was released on 2012-01-09 with total page 1342 pages. Available in PDF, EPUB and Kindle. Book excerpt: Issues in Energy Conversion, Transmission, and Systems: 2011 Edition is a ScholarlyEditions™ eBook that delivers timely, authoritative, and comprehensive information about Energy Conversion, Transmission, and Systems. The editors have built Issues in Energy Conversion, Transmission, and Systems: 2011 Edition on the vast information databases of ScholarlyNews.™ You can expect the information about Energy Conversion, Transmission, and Systems in this eBook to be deeper than what you can access anywhere else, as well as consistently reliable, authoritative, informed, and relevant. The content of Issues in Energy Conversion, Transmission, and Systems: 2011 Edition has been produced by the world’s leading scientists, engineers, analysts, research institutions, and companies. All of the content is from peer-reviewed sources, and all of it is written, assembled, and edited by the editors at ScholarlyEditions™ and available exclusively from us. You now have a source you can cite with authority, confidence, and credibility. More information is available at http://www.ScholarlyEditions.com/.
Download or read book Adaptive Mesh Refinement Method for CFD Applications written by Oscar Luis Antepara Zambrano and published by . This book was released on 2019 with total page 158 pages. Available in PDF, EPUB and Kindle. Book excerpt: The main objective of this thesis is the development of an adaptive mesh refinement (AMR) algorithm for computational fluid dynamics simulations using hexahedral and tetrahedral meshes. This numerical methodology is applied in the context of large-eddy simulations (LES) of turbulent flows and direct numerical simulations (DNS) of interfacial flows, to bring new numerical research and physical insight. For the fluid dynamics simulations, the governing equations, the spatial discretization on unstructured grids and the numerical schemes for solving Navier-Stokes equations are presented. The equations follow a discretization by conservative finite-volume on collocated meshes. For the turbulent flows formulation, the spatial discretization preserves symmetry properties of the continuous differential operators and the time integration follows a self-adaptive strategy, which has been well tested on unstructured grids. Moreover, LES model consisting of a wall adapting local-eddy-viscosity within a variational multi-scale formulation is used for the applications showed in this thesis. For the two-phase flow formulation, a conservative level-set method is applied for capturing the interface between two fluids and is implemented with a variable density projection scheme to simulate incompressible two-phase flows on unstructured meshes. The AMR algorithm developed in this thesis is based on a quad/octree data structure and keeps a relation of 1:2 between levels of refinement. In the case of tetrahedral meshes, a geometrical criterion is followed to keep the quality metric of the mesh on a reasonable basis. The parallelization strategy consists mainly in the creation of mesh elements in each sub-domain and establishes a unique global identification number, to avoid duplicate elements. Load balance is assured at each AMR iteration to keep the parallel performance of the CFD code. Moreover, a mesh multiplication algorithm (02) is reported to create large meshes, with different kind of mesh elements, but preserving the topology from a coarser original mesh. This thesis focuses on the study of turbulent flows and two-phase flows using an AMR framework. The cases studied for LES of turbulent flows applications are the flow around one and two separated square cylinders, and the flow around a simplified car model. In this context, a physics-based refinement criterion is developed, consisting of the residual velocity calculated from a multi-scale decomposition of the instantaneous velocity. This criteria ensures grid adaptation following the main vortical structures and giving enough mesh resolution on the zones of interest, i.e., flow separation, turbulent wakes, and vortex shedding. The cases studied for the two-phase flows are the DNS of 2D and 3D gravity-driven bubble, with a particular focus on the wobbling regime. A study of rising bubbles in the wobbling regime and the effect of dimensionless numbers on the dynamic behavior of the bubbles are presented. Moreover, the use of tetrahedral AMR is applied for the numerical simulation of gravity-driven bubbles in complex domains. On this topic, the methodology is validated on bubbles rising in cylindrical channels with different topology, where the study of these cases contributed to having new numerical research and physical insight in the development of a rising bubble with wall effects.
Download or read book An Adaptive Mesh Algorithm for Solving Systems of Time Dependent Partial Differential Equations written by David C. Arney and published by . This book was released on 1985 with total page 263 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis discusses and adaptive mesh algorithm that can be used with a finite difference or finite element scheme to solve initial-boundary value problems for vector systems of time dependent partial differential equations in two space dimensions. This algorithm combines the adaptive technique of mesh moving, static rezoning, and local mesh refinement. The nodes of a coarse mesh of quadrilateral cells are moved by a simple algebraic node movement function. The local mesh refinement method recursively divides cells of the moving coarse mesh within clustered regions that contain nodes with large error until a user prescribed error tolerance is satisfied. Keywords: Hyperbolic equations; Expert systems; and Computations.
Download or read book Adaptive Mesh Strategies for the Spectral Element Method written by Institute for Computer Applications in Science and Engineering and published by . This book was released on 1992 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt: An adaptive spectral element method has been developed for the efficient solution of time dependent partial differential equations. Adaptive mesh strategies that include resolution refinement and coarsening by three different methods are illustrated on solutions to the one-dimensional viscous Burgers equation and the two-dimensional Navier-Stokes equations for driven flow in a cavity. Sharp gradients, singularities and regions of poor resolution are resolved optimally as they develop in time using error estimators which indicate the choice of refinement to be used. The adaptive formulation presents significant increases in efficiency, flexibility and general capabilities for high order spectral methods.
Download or read book Costs and Savings of Adaptive Mesh Refinement written by Ragnhild Blikberg and published by . This book was released on 2001 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Adaptive Mesh Refinement Algorithm Development and Dissemination written by and published by . This book was released on 1997 with total page 9 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The project objective was to develop and disseminate adaptive mesh refinement (AMR) algorithms for structured and unstructured meshes. Development of ARM algorithms will continue along several directions. These directions include algorithms for parallel architectures, techniques for the solution of partial differential equations on adaptive meshes, mesh generation, and algorithms for nontraditional or generic applications of AMR. Dissemination of AMR algorithms is also a goal of the project. AMR algorithms are perceived as difficult to meld to current algorithms. The authors are developing tools that diminish this perception and allow more computational scientists to use AMR within their own work.
Download or read book An Adaptive Mesh Moving and Local Refinement Method for Time Dependent Partial Differential Equations written by and published by . This book was released on 1990 with total page 25 pages. Available in PDF, EPUB and Kindle. Book excerpt: We discuss mesh-moving, static mesh regeneration, and local mesh-refinement algorithms that can be used with a finite difference or finite element scheme to solve initial boundary value problems for vector systems of time-dependent partial differential equations in two space dimensions and time. A coarse based mesh of quadrilateral cells is moved by an algebraic mesh-movement function so as to follow and isolate spatially distinct phenomena. The local mesh-refinement method recursively divides the time step and spatial cells of the moving base mesh in regions where error indicators are high until a prescribed tolerance is satisfied. The static mesh-regeneration procedure is used to create a new base mesh when the existing one becomes to distorted. The adaptive methods have been combined with a MacCormack finite difference scheme for hyperbolic systems and an error indicator based upon estimates of the local discretization error obtained by Richardson extrapolation. Results are presented for several computational examples.
