Adaptive Mesh Refinement Algorithm Development And Dissemination
DOWNLOAD
Download Adaptive Mesh Refinement Algorithm Development And Dissemination PDF/ePub or read online books in Mobi eBooks. Click Download or Read Online button to get Adaptive Mesh Refinement Algorithm Development And Dissemination book now. This website allows unlimited access to, at the time of writing, more than 1.5 million titles, including hundreds of thousands of titles in various foreign languages. If the content not found or just blank you must refresh this page
Adaptive Mesh Refinement Algorithm Development And Dissemination
DOWNLOAD
Author :
language : en
Publisher:
Release Date : 1997
Adaptive Mesh Refinement Algorithm Development And Dissemination written by and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 1997 with categories.
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.
Adaptive Mesh Refinement Theory And Applications
DOWNLOAD
Author : Tomasz Plewa
language : en
Publisher: Springer Science & Business Media
Release Date : 2005-12-20
Adaptive Mesh Refinement Theory And Applications written by Tomasz Plewa and has been published by Springer Science & Business Media this book supported file pdf, txt, epub, kindle and other format this book has been release on 2005-12-20 with Mathematics categories.
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.
Structured Adaptive Mesh Refinement Samr Grid Methods
DOWNLOAD
Author : Scott B. Baden
language : en
Publisher: Springer Science & Business Media
Release Date : 2000
Structured Adaptive Mesh Refinement Samr Grid Methods written by Scott B. Baden and has been published by Springer Science & Business Media this book supported file pdf, txt, epub, kindle and other format this book has been release on 2000 with Computers categories.
The papers presented here describe research to improve the general understanding of the application of SAMR to practical problems, to identify issues critical to efficient and effective implementation on high performance computers, and to stimulate the development of a community code repository for software including benchmarks to assist in the evaluation of software and compiler technologies. The ten chapters have been divided into two parts: programming complexity of SAMR algorithms and the applicability and numerical challenges of SAMR methods.
An Adaptive Mesh Refinement Algorithm For The Discrete Ordinates Method
DOWNLOAD
Author :
language : en
Publisher:
Release Date : 1996
An Adaptive Mesh Refinement Algorithm For The Discrete Ordinates Method written by and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 1996 with categories.
Adaptive Mesh Refinement For A Finite Difference Scheme Using A Quadtree Decomposition Approach
DOWNLOAD
Author : Nandagopalan Auviur Srinivasa
language : en
Publisher:
Release Date : 2010
Adaptive Mesh Refinement For A Finite Difference Scheme Using A Quadtree Decomposition Approach written by Nandagopalan Auviur Srinivasa and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 2010 with categories.
Some numerical simulations of multi-scale physical phenomena consume a significant amount of computational resources, since their domains are discretized on high resolution meshes. An enormous wastage of these resources occurs in refinement of sections of the domain where computation of the solution does not require high resolutions. This problem is effectively addressed by adaptive mesh refinement (AMR), a technique of local refinement of a mesh only in sections where needed, thus allowing concentration of effort where it is required. Sections of the domain needing high resolution are generally determined by means of a criterion which may vary depending on the nature of the problem. Fairly straightforward criteria could include comparing the solution to a threshold or the gradient of a solution, that is, its local rate of change to a threshold. While the former criterion is not particularly rigorous and hardly ever represents a physical phenomenon of interest, it is simple to implement. However, the gradient criterion is not as simple to implement as a direct comparison of values, but it is still quick and a good indicator of the effectiveness of the AMR technique. The objective of this thesis is to arrive at an adaptive mesh refinement algorithm for a finite difference scheme using a quadtree decomposition approach. In the AMR algorithm developed, a mesh of increasingly fine resolution permits high resolution computation in sub-domains of interest and low resolution in others. In this thesis work, the gradient of the solution has been considered as the criterion determining the regions of the domain needing refinement. Initial tests using the AMR algorithm demonstrate that the paradigm adopted has considerable promise for a variety of research problems. The tests performed thus far depict that the quantity of computational resources consumed is significantly less while maintaining the quality of the solution. Analysis included comparison of results obtained with analytical solutions for four test problems, as well as a thorough study of a contemporary problem in solid mechanics.
A Parallel Adaptive Mesh Refinement Algorithm
DOWNLOAD
Author : James J. Quirk
language : en
Publisher:
Release Date : 1993
A Parallel Adaptive Mesh Refinement Algorithm written by James J. Quirk and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 1993 with categories.
An Adaptive Mesh Refinement Technique For Dynamics Of Solids
DOWNLOAD
Author : Abhishek Trivedi
language : en
Publisher:
Release Date : 2007
An Adaptive Mesh Refinement Technique For Dynamics Of Solids written by Abhishek Trivedi and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 2007 with categories.
Simulation of dynamics problems generally is heavily dependent on mesh size for convergence and accuracy. In many cases, the requirement of mesh size reaches to such proportions that the problem becomes unsolvable for the available computational resources. We perceive that such problems can be solved by refining and unrefining mesh adaptively during time stepping. Adaptive mesh refinement techniques available in popular literature are marred by various limitations, such as element-specific techniques, algorithm-specific techniques, etc. We utilize Conforming Hierarchical Refinement Methods (CHARMS) [32] for our purpose since it relies on the refinement of finite element basis instead of geometric sub-division of elements. Refinement in this fashion produces conforming meshes during adaptive mesh refinement for a wide range of elements. We improve CHARMS to incorporate time stepping problems. In order to show the effectiveness of such an algorithm, we modify an explicit Newmark solver to incorporate it within the adaptive mesh refinement framework. We perform the analysis of conservation properties of the modified algorithm to understand its limitations. Later, we demonstrate application of such development with a very practical example, simulation of an NDE experiment using ultrasonic guided waves. Details presented in [76] has shown that such a simulation would otherwise not have been possible. We further study the guided wave experiment and optimize various parameters of the algorithm to validate experimental results.
Adaptive Mesh Refinement Method For Cfd Applications
DOWNLOAD
Author : Oscar Luis Antepara Zambrano
language : en
Publisher:
Release Date : 2019
Adaptive Mesh Refinement Method For Cfd Applications written by Oscar Luis Antepara Zambrano and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 2019 with categories.
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.
Adaptive Mesh Refinement Algorithm Using Element Residuals
DOWNLOAD
Author : David Lyne Humphrey
language : en
Publisher:
Release Date : 1978
Adaptive Mesh Refinement Algorithm Using Element Residuals written by David Lyne Humphrey and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 1978 with Boundary value problems categories.
Energy And Water Development Appropriations For 1998
DOWNLOAD
Author : United States. Congress. House. Committee on Appropriations. Subcommittee on Energy and Water Development
language : en
Publisher:
Release Date : 1997
Energy And Water Development Appropriations For 1998 written by United States. Congress. House. Committee on Appropriations. Subcommittee on Energy and Water Development and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 1997 with Energy development categories.