The convergence

of the cascadic conjugate-gradient method

applied to elliptic problems

in domains with re-entrant corners

Authors:
Vladimir Shaidurov and Lutz Tobiska

Journal:
Math. Comp. **69** (2000), 501-520

MSC (1991):
Primary 65F10; Secondary 65N30

DOI:
https://doi.org/10.1090/S0025-5718-99-01138-2

Published electronically:
March 18, 1999

MathSciNet review:
1653982

Full-text PDF

Abstract | References | Similar Articles | Additional Information

Abstract: We study the convergence properties of the cascadic conjugate-gradient method (CCG-method), which can be considered as a multilevel method without coarse-grid correction. Nevertheless, the CCG-method converges with a rate that is independent of the number of unknowns and the number of grid levels. We prove this property for two-dimensional elliptic second-order Dirichlet problems in a polygonal domain with an interior angle greater than . For piecewise linear finite elements we construct special nested triangulations that satisfy the conditions of a ``triangulation of type '' in the sense of I. Babuska, R. B. Kellogg and J. Pitkäranta. In this way we can guarantee both the same order of accuracy in the energy norm of the discrete solution and the same convergence rate of the CCG-method as in the case of quasiuniform triangulations of a convex polygonal domain.

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Additional Information

**Vladimir Shaidurov**

Affiliation:
Institute of Computational Modelling, Siberian Branch of the Russian Academy of Sciences, Krasnoyarsk 660036, Russia

Email:
shidurov@cckr.krasnoyarsk.su

**Lutz Tobiska**

Affiliation:
Otto-von-Guericke-Universität Magdeburg, Postfach 4120, D-39016 Magdeburg, Germany

Email:
tobiska@mathematik.uni-magdeburg.de

DOI:
https://doi.org/10.1090/S0025-5718-99-01138-2

Keywords:
Multigrid,
cascadic algorithm,
conjugate-gradient method,
finite element method

Received by editor(s):
November 11, 1997

Received by editor(s) in revised form:
July 10, 1998

Published electronically:
March 18, 1999

Additional Notes:
The research was supported by the Deutsche Forschungsgemeinschaft.

Article copyright:
© Copyright 2000
American Mathematical Society