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Application of the multigrid method to grid generationThe multigrid method (MGM), used to numerically solve the pair of nonlinear elliptic equations commonly used to generate two dimensional boundary-fitted coordinate systems is discussed. Two different geometries are considered: one involving a coordinate system fitted about a circle and the other selected for an impinging jet flow problem. Two different relaxation schemes are tried: one is successive point overrelaxation and the other is a four-color scheme vectorizeable to take advantage of a parallel processor computer for greater computational speed. Results using MGM are compared with those using SOR (doing successive overrelaxations with the corresponding relaxation scheme on the fine grid only). It is found that MGM becomes significantly more effective than SOR as more accuracy is demanded and as more corrective grids, or more grid points, are used. For the accuracy required, it is found that MGM is two to three times faster than SOR in computing time. With the four-color relaxation scheme as applied to the impinging jet problem, the advantage of MGM over SOR is not as great. This may be due to the effect of a poor initial guess on MGM for this problem.
Document ID
19810006204
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Ohring, S.
(Naval Ship Research and Development Center Bethesda, MD, United States)
Date Acquired
August 11, 2013
Publication Date
January 1, 1980
Publication Information
Publication: NASA. Langley Research Center Numerical Grid Generation Tech.
Subject Category
Numerical Analysis
Accession Number
81N14718
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.
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