User's guide of Proceessing Modflow 5.0

106 Processing Modflow
MODFLOW < Solvers < SIP
The required parameters for the SIP package are specified in the Strongly Implicit Procedure
Package dialog box (Fig. 3.31). The parameters are described below:
< MXITER is the maximum number of iterations in one time step in an attempt to solve the
system of finite-difference equations.
< IPRSIP is the printout interval for this package. A positive integer is required. The
maximum head change (positive or negative) is saved in the run record file OUTPUT.DAT
for each iteration of a time step whenever the time step is an even multiple of IPRSIP. This
printout also occurs at the end of each stress period regardless of the value of IPRSIP.
< NPARM is the number of iteration parameters to be used. Five parameters are generally
sufficient.
< ACCL is the acceleration parameter. It must be greater than zero and is generally equal to
one.
< Head Change [L] is the head change criterion for convergence. When the maximum
absolute value of head change from all cells during an iteration is less than or equal to Head
Change, iteration stops.
MODFLOW < Solvers < SSOR
The required parameters for SSOR package are specified in the Slice Successive Overrelaxation
Package dialog box (Fig. 3.32). The parameters are described below:
< MXITER is the maximum number of iterations in one time step in an attempt to solve the
system of finite-difference equations.
< IPRSOR is the printout interval for SSOR. A positive integer is required. The maximum
head change (positive or negative) is saved in the run record file OUTPUT.DAT for each
iteration of a time step whenever the time step is an even multiple of IPRSOR. This printout
also occurs at the end of each stress period regardless of the value of IPRSOR.
< ACCL is the acceleration parameter, usually between 1.0 and 2.0.
< Head Change is the head change criterion for convergence. When the maximum absolute
value of head change from all cells during an iteration is less than or equal to Head Change,
iteration stops.
3.6.1 MODFLOW