Approximate Schur complement preconditioning of the lowest order nodal discretizations

Conference · 31 December 1996

DOI:https://doi.org/10.1137/S1064827596303491· OSTI ID:433355

Moulton, J D; Ascher, U M ^[1]; Morel, J E ^[2]

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1. Univ. of British Columbia, Vancouver, British Columbia (Canada)
2. Los Alamos National Lab., NM (United States)

Particular classes of nodal methods and mixed hybrid finite element methods lead to equivalent, robust and accurate discretizations of 2nd order elliptic PDEs. However, widespread popularity of these discretizations has been hindered by the awkward linear systems which result. The present work exploits this awkwardness, which provides a natural partitioning of the linear system, by defining two optimal preconditioners based on approximate Schur complements. Central to the optimal performance of these preconditioners is their sparsity structure which is compatible with Dendy`s black box multigrid code.

• Research Organization: Front Range Scientific Computations, Inc., Lakewood, CO (United States)
• OSTI ID: 433355
• Report Number(s): CONF-9604167--Vol.1; ON: DE96015306
• Country of Publication: United States
• Language: English

Related Subjects

22 GENERAL STUDIES OF NUCLEAR REACTORS
99 GENERAL AND MISCELLANEOUS
ACCURACY
EFFICIENCY
FINITE ELEMENT METHOD
ITERATIVE METHODS
NODAL EXPANSION METHOD
REACTOR PHYSICS