Print Email Facebook Twitter A comparison of deflation and coarse grid correction applied to porous media flow Title A comparison of deflation and coarse grid correction applied to porous media flow Author Nabben, R. Vuik, C. Faculty Electrical Engineering, Mathematics and Computer Science Date 2003 Abstract In this paper we compare various preconditioners for the numerical solution of partial dierential equations. We compare a coarse grid correction preconditioner used in domain decomposition methods with a so-called deflation preconditioner. We prove that the effective condition number of the de ated preconditioned system is always, i.e. for all deflation vectors and all restrictions and prolongations, below the condition number of the system preconditioned by the coarse grid correction. This implies that the Conjugate Gradient method applied to the de ated preconditioned system converges always faster than the Conjugate Gradient method applied to the system preconditioned by the coarse grid correction. Numerical results for porous media flows emphasize the theoretical results. Subject deflationcoarse grid correctionpreconditionersconjugate gradientsporous media flowscalable parallel preconditioner To reference this document use: http://resolver.tudelft.nl/uuid:ccf494cc-809d-447f-b682-0f9efbcc3be5 Publisher Delft University of Technology, Faculty of Electrical Engineering, Mathematics and Computer Science, Delft Institute of Applied Mathematics ISSN 1389-6520 Source Reports of the Department of Applied Mathematical Analysis, 03-10 Part of collection Institutional Repository Document type report Rights (c) 2003 Department of Applied Mathematical Analysis Files PDF nabben-03-10.pdf 225.7 KB Close viewer /islandora/object/uuid:ccf494cc-809d-447f-b682-0f9efbcc3be5/datastream/OBJ/view