Please use this identifier to cite or link to this item:
|Title:||Block preconditioners for symmetric indefinite linear systems||Authors:||Toh, K.-C.
Quasi-minimal residual method
Symmetric indefinite system
|Issue Date:||28-Jun-2004||Citation:||Toh, K.-C., Phoon, K.-K., Chan, S.-H. (2004-06-28). Block preconditioners for symmetric indefinite linear systems. International Journal for Numerical Methods in Engineering 60 (8) : 1361-1381. ScholarBank@NUS Repository. https://doi.org/10.1002/nme.982||Abstract:||This paper presents a systematic theoretical and numerical evaluation of three common block preconditioners in a Krylov subspace method for solving symmetric indefinite linear systems. The focus is on large-scale real world problems where block approximations are a practical necessity. The main illustration is the performance of the block diagonal, constrained, and lower triangular preconditioners over a range of block approximations for the symmetric indefinite system arising from large-scale finite element discretization of Biot's consolidation equations. This system of equations is of fundamental importance to geomechanics. Numerical studies show that simple diagonal approximations to the (1,1) block K and inexpensive approximations to the Schur complement matrix S may not always produce the most spectacular time savings when K is explicitly available, but is able to deliver reasonably good results on a consistent basis. In addition, the block diagonal preconditioner with a negative (2,2) block appears to be reasonably competitive when compared to the more complicated ones. These observation are expected to remain valid for coefficient matrices whereby the (1,1) block is sparse, diagonally significant (a notion weaker than diagonal dominance), moderately well-conditioned, and has a much larger block size than the (2,2) block. © 2004 John Wiley and Sons, Ltd.||Source Title:||International Journal for Numerical Methods in Engineering||URI:||http://scholarbank.nus.edu.sg/handle/10635/65243||ISSN:||00295981||DOI:||10.1002/nme.982|
|Appears in Collections:||Staff Publications|
Show full item record
Files in This Item:
There are no files associated with this item.
checked on Jul 21, 2019
WEB OF SCIENCETM
checked on Jul 13, 2019
checked on Jul 21, 2019
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.