TY - GEN
T1 - Solving nonlinear systems inside implicit time integration schemes for unsteady viscous flows
AU - Birken, P.
PY - 2013
Y1 - 2013
N2 - We considered nonlinear solvers inside implicit time integration schemes for the time dependent compressible Navier-Stokes equations. The existing solvers turn out to be adequate, but amenable to significant improvements. Regarding multigrid schemes, we demonstrated that reoptimizing a multigrid scheme for the case of a time dependent equation leads to significant improvements in convergence speed compared to reusing the steady state method. As for Newton schemes, inexact Jacobian-free Newton-GMRES methods using the Eisenstat-Walker strategy are easy to implement and fast and, as opposed to the situation for steady flows, a true alternative to multigrid.
AB - We considered nonlinear solvers inside implicit time integration schemes for the time dependent compressible Navier-Stokes equations. The existing solvers turn out to be adequate, but amenable to significant improvements. Regarding multigrid schemes, we demonstrated that reoptimizing a multigrid scheme for the case of a time dependent equation leads to significant improvements in convergence speed compared to reusing the steady state method. As for Newton schemes, inexact Jacobian-free Newton-GMRES methods using the Eisenstat-Walker strategy are easy to implement and fast and, as opposed to the situation for steady flows, a true alternative to multigrid.
U2 - 10.1007/978-3-642-33221-0_4
DO - 10.1007/978-3-642-33221-0_4
M3 - Paper in conference proceeding
SN - 9783642332203
T3 - Notes on Numerical Fluid Mechanics and Multidisciplinary Design
SP - 57
EP - 71
BT - Recent Developments in the Numerics of Nonlinear Hyperbolic Conservation Laws
A2 - Ansorge, Rainer
A2 - Bijl, Hester
A2 - Meister, Andreas
A2 - Sonar, Thomas
PB - Springer
T2 - Recent Developments in the Numerics of Nonlinear Hyperbolic Conservation Laws and their Use in Science and Engineering
Y2 - 15 January 2012 through 21 January 2012
ER -