eprintid: 5845
rev_number: 8
eprint_status: archive
userid: 1
dir: disk0/00/00/58/45
datestamp: 2005-01-19 13:55:16
lastmod: 2015-04-23 10:14:59
status_changed: 2012-08-14 15:16:19
type: preprint
metadata_visibility: show
creators_name: Johannsen, Klaus
title: A robust 9-point ILU smoother for anisotropic problems
ispublished: pub
subjects: 510
divisions: 708000
keywords: ILU Faktorisierung , robuste Mehrgitterverfahren , dünn-besetze matrizen , Fourieranalyseanisotropic diffusion , ILU factorization , robust multigrid method , sparse matrices , Fourier analysis
cterms_swd: anisotrope Diffusion
abstract: Discrete systems arising from elliptic PDEs can be solved efficiently using multigrid methods. In many cases of practical interest the resulting linear equations exhibit strong anisotropies. It is well-known that standard multigrid methods fail to work for this type of problems. Various ILU methods have been proposed and investigated to overcome these difficulties. To be applied successfully, they usually require a modification of the ILU iteration. Only in the particular case of a 7-point decomposition for a 5-point discretization no modification is needed. We give a new proof for this situation, showing in which way the smoothing property is related to the size of the restmatrix. The method is shown to carry over to 9-point finite element discretizations. Numerical experiments document the excellent smoothing properties.
abstract_translated_lang: eng
class_scheme: msc
class_labels: 65F10, 65N55, 65F50, 65N22, 65N30
date: 2005
date_type: published
id_scheme: DOI
id_number: 10.11588/heidok.00005845
portal_cluster_id: p-iwrpp
portal_order: 05845
ppn_swb: 1646174968
own_urn: urn:nbn:de:bsz:16-heidok-58458
language: eng
bibsort: JOHANNSENKAROBUST9PO2005
full_text_status: public
series: IWR-Preprints
citation:   Johannsen, Klaus  (2005) A robust 9-point ILU smoother for anisotropic problems.  [Preprint]     
document_url: https://archiv.ub.uni-heidelberg.de/volltextserver/5845/1/doc.pdf