Acceleration of the Generialized Global Basis (GGB) method for nonlinear problems.

Journal Article · Thu Jul 01 04:00:00 EDT 2004 · Proposed for publication in Journal of Computational Physics.

OSTI ID:964572

Shadid, John Nicolas ^[1]; Fish, Jacob ^[2]; Waisman, Haim ^[2]; Tuminaro, Raymond Stephen

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1. Sandia National Laboratories, Albuquerque, NM
2. Polytechnic Institute, Troy, NY

Two heuristic strategies intended to enhance the performance of the generalized global basis (GGB) method [H. Waisman, J. Fish, R.S. Tuminaro, J. Shadid, The Generalized Global Basis (GGB) method, International Journal for Numerical Methods in Engineering 61(8), 1243-1269] applied to nonlinear systems are presented. The standard GGB accelerates a multigrid scheme by an additional coarse grid correction that filters out slowly converging modes. This correction requires a potentially costly eigen calculation. This paper considers reusing previously computed eigenspace information. The GGB? scheme enriches the prolongation operator with new eigenvectors while the modified method (MGGB) selectively reuses the same prolongation. Both methods use the criteria of principal angles between subspaces spanned between the previous and current prolongation operators. Numerical examples clearly indicate significant time savings in particular for the MGGB scheme.

• Research Organization: Sandia National Laboratories
• Sponsoring Organization: USDOE
• DOE Contract Number: AC04-94AL85000
• OSTI ID: 964572
• Report Number(s): SAND2004-3266J
• Journal Information: Proposed for publication in Journal of Computational Physics., Journal Name: Proposed for publication in Journal of Computational Physics.
• Country of Publication: United States
• Language: English

Related Subjects

97 MATHEMATICS AND COMPUTING
99 GENERAL AND MISCELLANEOUS
CALCULATION METHODS
COMPUTER CALCULATIONS
CORRECTIONS
EIGENVECTORS
NONLINEAR PROBLEMS
PERFORMANCE