Multigrid Inputs
The following inputs can be set directly in the AMReX solver classes but we set them via the MFIX-Exa routines because we may want different inputs for the different solvers called by MFIX-Exa. NOTE: the nodal solver settings are read in directly by AMReX, the MAC and diffusion settings by MFIX-Exa.
These control the nodal projection and must be preceded by “nodal_proj.”:
Description |
Type |
Default |
|
verbose |
Verbosity of multigrid solver in nodal projection |
Int |
0 |
bottom_verbose |
Verbosity of BiCGStab solver in nodal projection |
Int |
0 |
mg_rtol |
Relative tolerance in nodal projection |
Real |
1.e-11 |
mg_atol |
Absolute tolerance in nodal projection |
Real |
1.e-14 |
maxiter |
Maximum number of iterations in the nodal projection |
Int |
100 |
bottom_maxiter |
Maximum number of iterations in the nodal projection bottom solver if using bicg, cg, bicgcg or cgbicg |
Int |
100 |
mg_max_coarsening_level |
Maximum number of coarser levels to allowin the nodal projection If set to 0, the bottom solver will be called at the current level |
Int |
100 |
bottom_solver |
Which bottom solver to use in the nodal projection Options are bicgcg, bicgstab, cg, cgbicg, smoother or hypre |
String |
bicgcg |
hypre_namespace |
Namespace to use in the nodal projection when using hypre to control hypre specific settings. It can be any string. |
String |
hypre |
hypre_interface |
Which interface to use in the nodal projection when using hypre Options are ij, semi_structured or structured |
String |
ij |
These control the MAC projection and must be preceded by “mac_proj.”:
Description |
Type |
Default |
|
---|---|---|---|
verbose |
Verbosity of multigrid solver in MAC projection |
Int |
0 |
bottom_verbose |
Verbosity of BiCGStab solver in MAC projection |
Int |
0 |
mg_rtol |
Relative tolerance in MAC projection |
Real |
1.e-11 |
mg_atol |
Absolute tolerance in MAC projection |
Real |
1.e-14 |
maxiter |
Maximum number of iterations in the MAC projection |
Int |
200 |
bottom_maxiter |
Maximum number of iterations in the MAC projection bottom solver if using bicg, cg, bicgcg or cgbicg |
Int |
200 |
mg_max_coarsening_level |
Maximum number of coarser levels to allow in the MAC projection If set to 0, the bottom solver will be called at the current level |
Int |
100 |
bottom_solver |
Which bottom solver to use in the MAC projection Options are bicgcg, bicgstab, cg, cgbicg, smoother or hypre |
String |
bicgcg |
hypre_namespace |
Namespace to use in the MAC projection when using hypre to control hypre specific settings. It can be any string. |
String |
hypre |
hypre_interface |
Which interface to use in the MAC projection when using hypre Options are ij, semi_structured or structured |
String |
ij |
NOTE: If the nodal_proj
and mac_proj
hypre_namespace
’s are set, they must be distinct unless set to
hypre
, in which case the default behavior is recovered in which case hypre settings apply to all solvers.
These control the diffusion solver and must be preceded by “diffusion.”:
Description |
Type |
Default |
|
---|---|---|---|
verbose |
Verbosity of linear solver for diffusion solve |
Int |
0 |
bottom_verbose |
Verbosity of BiCGStab solver in diffusion solve |
Int |
0 |
mg_rtol |
Relative tolerance in diffusion solve |
Real |
1.e-11 |
mg_atol |
Absolute tolerance in diffusion solve |
Real |
1.e-14 |
maxiter |
Maximum number of iterations in diffusion solve |
Int |
100 |
bottom_maxiter |
Maximum number of iterations in diffusion solve bottom solver if using bicg, cg, bicgcg or cgbicg |
Int |
100 |
mg_max_coarsening_level |
Maximum number of coarser levels to allow in diffusion solve If set to 0, the bottom solver will be called at the current level |
Int |
100 |
bottom_solver |
Which bottom solver to use in the diffusion solve Options are bicgcg, bicgstab, cg, cgbicg, or smoother |
String |
bicgcg |