Download or read book Iterative Solution of Saddle Point Problems Using Divergence free Finite Elements with Applications to Groundwater Flow written by Robert Scheichl and published by . This book was released on 2000 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Iterative Solution of Saddle Point Problems with Applications to Groundwater Flow written by Robert Scheichl and published by . This book was released on 2000 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book SIAM Journal on Scientific Computing written by and published by . This book was released on 2002 with total page 780 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Finite Elements in Water Resources written by J. P. Laible and published by Springer Science & Business Media. This book was released on 2013-04-17 with total page 805 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is the edited proceedings of the Fifth International Conference on Finite Elements in Water Resources, held at the University of Vermont, USA in June 1984. This Conference cont inues the successful series started at Princeton University in 1976, followed by the Conference in Imperial College, London, UK in 1978, the third Conference at the University of Mississippi, USA in 1980 and the fourth at the University of Hannover, Germany in 1982. The objective of this Conference is to provide engineers and scientists interested in water resources with the state-of-t- art on finite element modelling. The Proceedings review the basic theory and applications of the technique in groundwater and seepage, transport phenomena, viscous flow, river, lake and ocean modelling. The fundamentals of the numerical techniques employed in finite elements are also discussed. Many applications illus trate the versatility and generality of the Finite Element Method for the simulation of a wide range of problems in water resources. More recent schemes, in particular, boundary elements, are also presented, together with a series of advanced numerical techniques. The Conference has become an internationally accepted forum for the presentation of new developments of finite elements in water resources techniques. Because of this, a large number of abstracts were submitted to the Organizing Committee and it is our only reg ret that it was impossible to accept all these contributions. The overwhelming response to our Call for Papers has ensured the high quality of these proceedings.
Download or read book Finite Element Techniques in Groundwater Flow Studies written by I. Kazda and published by Elsevier. This book was released on 2012-12-02 with total page 328 pages. Available in PDF, EPUB and Kindle. Book excerpt: The finite element method (FEM) is one of those modern numerical methods whose rise and development was incited by the rapid development of computers. This method has found applications in all the technical disciplines as well as in the natural sciences.One of the most effective applications of the finite element method is its use for the solution of groundwater flow problems encountered in the design and maintenance of hydraulic structures and tailing dams, in soil mechanics, hydrology, hydrogeology and engineering geology.The stimuli to write this book came from the results obtained in the solution of practical problems connected both with the construction and maintenance of fill-type dams and tailing dams and the utilization of groundwater in Czechoslovakia, and on the other hand from the experience gained in teaching hydraulic structures theory at the Faculty of Civil Engineering of the Technical University of Prague. All the experience so far obtained shows markedly the advantages of the finite element method and the great possibilities of its further development as well as its considerable demands on the algorithmization, programming and use of computer possibilities. The reader will find an explanation of the fundamentals of the finite element method directed mainly toward isoparametric elements having an exceptional adaptability and numerical reliability. The finite element method application to groundwater flow concerns mainly two-dimensional problems, which occur most frequently in practice. Considerable attention is given to non-linear and non-stationary problems, which are most important in application.A computer program (based on the eight-noded isoparametric elements) is included and fully documented.The book will be useful to civil engineers, hydrogeologists and engineering geologists who need the finite element method as a solution tool for the complex problems encountered in engineering practice.
Download or read book Index to Theses with Abstracts Accepted for Higher Degrees by the Universities of Great Britain and Ireland and the Council for National Academic Awards written by and published by . This book was released on 2001 with total page 372 pages. Available in PDF, EPUB and Kindle. Book excerpt: Theses on any subject submitted by the academic libraries in the UK and Ireland.
Download or read book Constraint Preconditioning of Saddle Point Problems written by Scott Aaron Ladenheim and published by . This book was released on 2015 with total page 88 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis is concerned with the fast iterative solution of linear systems of equations of saddle point form. Saddle point problems are a ubiquitous class of matrices that arise in a host of computational science and engineering applications. The focus here is on improving the convergence of iterative methods for these problems by preconditioning. Preconditioning is a way to transform a given linear system into a different problem for which iterative methods converge faster. Saddle point matrices have a very specific block structure and many preconditioning strategies for these problems exploit this structure. The preconditioners considered in this thesis are constraint preconditioners. This class of preconditioner mimics the structure of the original saddle point problem. In this thesis, we prove norm- and field-of-values-equivalence for constraint preconditioners associated to saddle point matrices with a particular structure. As a result of these equivalences, the number of iterations needed for convergence of a constraint preconditioned minimal residual Krylov subspace method is bounded, independent of the size of the matrix. In particular, for saddle point systems that arise from the finite element discretization of partial differential equations (p.d.e.s), the number of iterations it takes for GMRES to converge for theses constraint preconditioned systems is bounded (asymptotically), independent of the size of the mesh width. Moreover, we extend these results when appropriate inexact versions of the constraint preconditioner are used. We illustrate this theory by presenting numerical experiments on saddle point matrices that arise from the finite element solution of coupled Stokes-Darcy flow. This is a system of p.d.e.s that models the coupling of a free flow to a porous media flow by conditions across the interface of the two flow regions. We present experiments in both two and three dimensions, using different types of elements (triangular, quadrilateral), different finite element schemes (continuous, discontinuous Galerkin methods), and different geometries. In all cases, the effectiveness of the constraint preconditioner is demonstrated.
Download or read book Preprints of Papers written by and published by . This book was released on 1980 with total page 996 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Finite Element Solution of Steady State Potential Flow Problems written by Hydrologic Engineering Center (U.S.) and published by . This book was released on 1970 with total page 94 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Testing Parallel Linear Iterative Solvers for Finite Element Groundwater Flow Problems written by and published by . This book was released on 2007 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt: The modeling of groundwater flow using three-dimensional finite element discretizations creates a need to solve large systems of sparse linear equations (Ax = b) at each of several nonlinear iterations. These linear systems can be difficult to solve because of the ill-conditioning of the matrix A resulting from the widely varying magnitudes of its coefficients. Because the meshes may contain millions of nodes, iterative solvers are typically used to perform the Ax = b solution. Since 80 percent or more of the computational time is spent in the iterative solver part of the computer program, choosing the most efficient solver for each application can dramatically reduce the total solution time. This paper tests 12 Krylov subspace parallel linear iterative solvers with five preconditioners (60 scenarios) on linear systems of equations resulting from a finite element study of remediation of a military site using pump-and-treat technology. Both symmetric, positive-definite matrices, resulting from a Picard linearization of the nonlinear equations for the steady-state case, and nonsymmetric matrices, arising from a Newton linearization of the nonlinear equations of a transient case, are studied The Portable Extensible Toolkit for Scientific Computation (PETSc) library was used in this study on the Engineer Research and Development Center Major Shared Resource Center SG1 O3K and Cray XT3 computers. Matrix data corresponding to each subdomain in a parallel groundwater finite element program were first written to a file in a compressed sparse column format. A separate program was then written in FORTRAN to read these data, renumber the nodes, call the PETSc routines to load A and b and then solve for x, and finally compute error norms. Solver time, iteration count, 2-norm and infinity-norm of the residual after convergence, weak speedup, and strong speedup are tabulated in this paper for the different scenarios and then analyzed.
Download or read book Analysis and Finite Element Approximations of Parabolic Saddle Point Problems with Applications to Optimal Control written by Konstantinos Chrysafinos and published by . This book was released on 2002 with total page 160 pages. Available in PDF, EPUB and Kindle. Book excerpt: We present some results concerning boundary optimal control problems and related initial-boundary value problems. We prove the existence and uniqueness of the solution of a parabolic saddle point problem, as well as the existence and uniqueness of a penalized and an iterated penalized saddle point problem. Moreover, we derive semi discrete error estimates for the finite element approximation of the penalized saddle point problem, and semi discrete error estimates for the penalized and unpenalized heat equation with nonhomogeneous boundary data under minimal regularity assumptions. Finally, we use the above results for the analysis and finite element analysis of boundary optimal control problems having states constrained to parabolic partial differential equations.
Download or read book Finite Elements in Water Resources written by António Sá Costa and published by . This book was released on 1986 with total page 840 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Modular Finite element Model MODFE for Areal and Axisymmetric Ground water Flow Problems written by Richard L. Cooley and published by . This book was released on 1992 with total page 120 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book British National Bibliography for Report Literature written by and published by . This book was released on 2001-08 with total page 88 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Advanced Applications of the Boundary Element Method to Groundwater Flow in Fractured Rock and Free Surface Hydrodynamics written by Daniel Ernesto Medina and published by . This book was released on 1989 with total page 430 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Groundwater Modeling by the Finite Element Method written by J. D. Istok and published by American Geophysical Union. This book was released on 1989 with total page 520 pages. Available in PDF, EPUB and Kindle. Book excerpt: Published by the American Geophysical Union as part of the Water Resources Monograph Series, Volume 13. The finite element method is now widely used to solve a variety of important problems in the field of groundwater hydrology. Thus a clear understanding of the method is essential to scientists and engineers working in this field. The goal of this book is to provide the reader with the basic skills needed to use the finite element method to solve "real-world" problems. Examples are used throughout the text to illustrate each step in the solution process.
Download or read book Finite Element Simulation in Surface and Subsurface Hydrology written by George Francis Pinder and published by . This book was released on 1977 with total page 326 pages. Available in PDF, EPUB and Kindle. Book excerpt:
