Title
Krylov-Subspace Recycling via the POD-Augmented Conjugate-Gradient Method.
Abstract
This work presents a new Krylov-subspace-recycling method for efficiently solving sequences of linear systems of equations characterized by varying right-hand sides and symmetric positive-definite matrices. As opposed to typical truncation strategies used in recycling such as deflation, we propose a truncation method inspired by goal-oriented proper orthogonal decomposition (POD) from model reduction. This idea is based on the observation that model reduction aims to compute a low-dimensional subspace that contains an accurate solution; as such, we expect the proposed method to generate a low-dimensional subspace that is well suited for computing solutions that can satisfy inexact tolerances. In particular, we propose specific goal-oriented POD "ingredients" that align the optimality properties of POD with the objective of Krylov-subspace recycling. To compute solutions in the resulting "augmented" POD subspace, we propose a hybrid direct/iterative three-stage method that leverages (1) the optimal ordering of POD basis vectors, and (2) well-conditioned reduced matrices. Numerical experiments performed on solid-mechanics problems highlight the benefits of the proposed method over existing approaches for Krylov-subspace recycling.
Year
DOI
Venue
2016
10.1137/16M1057693
SIAM JOURNAL ON MATRIX ANALYSIS AND APPLICATIONS
Keywords
DocType
Volume
Krylov-subspace recycling,proper orthogonal decomposition,augmented Krylov methods,model reduction,conjugate-gradient method
Journal
37
Issue
ISSN
Citations 
3
0895-4798
2
PageRank 
References 
Authors
0.45
9
3
Name
Order
Citations
PageRank
Kevin Carlberg19310.20
Virginia Forstall230.80
Ray S. Tuminaro344738.09