Solver packages

One of the following solvers must be specified for a model run. All arguments for the solver are non-spatial values.

PCG package

The preconditioned conjugate-gradient package can be enabled with

res = mf::setPCG(MXITER, ITERI, NPCOND, HCLOSE, RCLOSE, RELAX, NBPOL, DAMP);

where

MXITER
is the maximum number of outer iterations;
ITERI
is the number of inner iterations;
NPCOND
1 - Modified Incomplete Cholesky, 2 - Polynomial matrix conditioning method;
HCLOSE
is the head change criterion for convergence;
RCLOSE
is the residual criterion for convergence;
RELAX
is the relaxation parameter used with NPCOND = 1;
NBPOL
indicates whether the estimate of the upper bound on the maximum eigenvalue is 2.0 and
DAMP
is the damping factor.

SOR package

The slice-successive overrelaxation package can be enabled with

res = mf::setSOR(MXITER, ACCL, HCLOSE);

where

MXITER
is the maximum number of iterations allowed in a time step;
ACCL
is the acceleration variable and
HCLOSE
the head change criterion for convergence.

SIP package

The strongly implicit procedure package can be enabled with

res = mf::setSIP(MXITER, NPARAM, ACCL, HCLOSE, IPCALC, WSEED);

where

MXITER
is the maximum number of times through the iteration loop in one time step;
NPARAM
is the number of iteration variables to be used;
ACCL
is the acceleration variable;
IPCALC
0 - the seed entered by the user will be used, 1 - the seed will be calculated at the start of the simulation, and
WSEED
is the seed for calculating iteration variables.

DSP package

The direct solver package can be enabled with

res = mf::setDSP(ITMX, MXUP, MXLOW, MXBW, IFREQ, ACCL, HCLOSE);

where

ITMX
is the maximum number of iterations each time step;
MXUP
is the maximum number of equations in the upper part of the equations to be solved;
MXLOW
is the maximum number of equations in the lower part of equations to be solved;
MXBW
is the maximum band width plus 1 of the [AL] matrix;
IFREQ
is flag indicating the frequency at which coefficients in [A] change;
ACCL
is a multiplier for the computed head change for each iteration and
HCLOSE
is the head change closure criterion.

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