Thursday, December 15, 9:30 am in room MTH 3206, University of Maryland,
College Park
Fast Nonsymmetric Iterations and Preconditioning for Navier-Stokes
Equations
Prof. Howard Elman
Department of Computer Science and UMIACS
University of Maryland at College Park
elman@cs.umd.edu
Discretization and linearization of the steady-state Navier-Stokes equations
gives rise to a nonsymmetric indefinite linear system of equations. We
present preconditioning techniques for such systems with the property that the
eigenvalues of the preconditioned matrices are bounded independently of the
mesh size used in the discretization. We confirm and supplement these analytic
results with a series of numerical experiments indicating that Krylov subspace
iterative methods for nonsymmetric systems display rates of convergence that
are independent of the mesh parameter. In addition, we show that
preconditioning costs can be kept small by using iterative methods for some
intermediate steps performed by the preconditioner.
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