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0857f479a8
using a run-time selectable preconditioner
References:
Van der Vorst, H. A. (1992).
Bi-CGSTAB: A fast and smoothly converging variant of Bi-CG
for the solution of nonsymmetric linear systems.
SIAM Journal on scientific and Statistical Computing, 13(2), 631-644.
Barrett, R., Berry, M. W., Chan, T. F., Demmel, J., Donato, J.,
Dongarra, J., Eijkhout, V., Pozo, R., Romine, C. & Van der Vorst, H.
(1994).
Templates for the solution of linear systems:
building blocks for iterative methods
(Vol. 43). Siam.
See also: https://en.wikipedia.org/wiki/Biconjugate_gradient_stabilized_method
Tests have shown that PBiCGStab with the DILU preconditioner is more
robust, reliable and shows faster convergence (~2x) than PBiCG with
DILU, in particular in parallel where PBiCG occasionally diverges.
This remarkable improvement over PBiCG prompted the update of all
tutorial cases currently using PBiCG to use PBiCGStab instead. If any
issues arise with this update please report on Mantis: http://bugs.openfoam.org
Stiff chemistry solver validation test cases gri : GRI-Mech 3.0. CH4 combustion, 53 species, 325 reactions h2 : H2 combustion, 10 species, 27 reactions nc7h16 : n-Heptane combustion, 544 species, 2446 reactions ic8h18 : iso-Octane combustion, 874 species, 3796 reactions Results interpreted in 'validation' sub-directory, where OpenFOAM results are compared against those predicted by CHEMKIN II. Overall the best performing ODE solver is seulex followed closely by rodas23.