ctrl

    Assign various control parameters needed for equation solvers and matrix solver routines. Suggested values for the control parameters are shown in “{ }” in the table. For older input files where MAXSOLVE and ACCM were not input, the default is ACCM = gmre and MAXSOLVE = 3*NORTH.

    • Group 1 - MAXIT, EPM, NORTH, MAXSOLVE, ACCM
    • Group 2 - JA, JB, JC, NAR
    • Group 3 - AAW, AGRAV, UPWGT
    • Group 4 - IAMM, AIAA, DAYMIN, DAYMAX
    • Group 5 - ICNL, LDA
    Input Variable Format Default Description
    MAXIT integer   Maximum number of iterations allowed in either the overall Newton cycle or the inner cycle to solve for the corrections at each iteration. If MAXIT < 0 then the maximum number of iterations is ABS(MAXIT) but the minimum number of iterations is set to 2. {10}
    EPM real   Tolerance for Newton cycle (nonlinear equation tolerance). Note - EPM gets overwritten by TMCH in ITER macro if that variable is defined. {1.e-5}
    NORTH integer   Number of orthogonalizations in the linear equation solver. Note - for more complicated problems, increase NORTH. For example, for fully coupled stress problems recommend using a value of 80 and gmre. {8 for gmre, 1 for bcgs}
    MAXSOLVE integer   Maximum number of solver iterations per Newton iteration allowed. {100}
    ACCM character*4   Acceleration method for solver bcgs - Biconjugate gradient stabilized acceleration. Recommended for isothermal steady-state saturated flow problems. gmre - Generalized minimum residual acceleration. Recommended for all other types of problems.
    NAR integer 1 The order of partial Gauss elimination {1 or 2 is recommended}. Larger values increase memory utilization but may be necessary for convergence.
    AAW real   Implicitness factor. {1}AAW ‚⧠1, use standard pure implicit formulation.AAW > 1, use second-order implicit method.
    AGRAV integer   Direction of gravity AGRAV = 0, no gravity is used.AGRAV = 1, X-direction.AGRAV = 2, Y-direction.AGRAV = 3, Z-direction.A value for gravity of 9.81 m/s2 is used in the code when AGRAV ‚â 0. If AGRAV > 3, AGRAV is set equal to 3.
    UPWGT real   Value of upstream weighting {1.0}.If UPWGT < 0.5, UPWGT is set to 0.5If UPWGT > 1.0, UPWGT is set to 1.0
    IAMM integer   Maximum number of iterations for which the code will multiply the time step size. If this number of time steps is exceeded at any time, the time step will not be increased for the next time. Set IAMM < MAXIT {7-10}.
    AIAA real 1 Time step multiplier {1.2-2.0}
    DAYMIN real 1.0e-05 Minimum time step size (days)
    DAYMAX real 30.0 Maximum time step size (days)
    ICNL integer   Parameter that specifies the geometry: ICNL = 0, three-dimensional. ICNL = 1, X - Y plane. ICNL = 2, X - Z plane. ICNL = 3, Y - Z plane. ICNL = 4, X - Y radial plane, (radius is X). ICNL = 5, X - Z radial plane, (radius is X). ICNL = 6, Y - Z radial plane, (radius is Y)
    LDA integer 0 Parameter that specifies the external storage of geometric coefficients: LDA = -2, element coefficients are calculated in the code and saved, unformatted, on file filen.stor. LDA = -1, element coefficients are calculated in the code and saved on file filen.stor. LDA = 0, element coefficients are calculated in the code and not saved. LDA = +1, element coefficients are read from file filen.stor and no coefficients are calculated in the code. LDA = +2, element coefficients are read, unformatted, from file filen.stor and no coefficients are calculated in the code. LDA = +5, element coefficients are read from file filen.stor and no coefficients are calculated in the code. Coefficients are re-saved unformatted, on filen_UNF.stor. LDA = +6, element coefficients are read from file filen.stor and no coefficients are calculated in the code. Coefficients are re-saved formatted, on filen_FOR.stor. LDA = +7, element coefficients are read, unformatted, from file filen.stor and no coefficients are calculated in the code. Coefficients are re-saved unformatted, on filen_UNF.stor. LDA = +8, element coefficients are read, unformatted, from file filen.stor and no coefficients are calculated in the code. Coefficients are re-saved formatted, on filen_FOR.stor. It should be noted that if the coefficients are read from a file (LDA > 0) then the macro nfinv is ignored as well as information read from macros elem and coor since the coefficients are not being calculated.

    The following is an example of ctrl. In this example, the maximum number of iterations allowed is 40, tolerance for solving the nonlinear equations using Newton iterations is 1.e-7, and the number of orthogonalizations in the linear equation solver is 8. The order of partial Gauss elimination for all nodes 1 through 140 is 1. A forward implicit formulation is used for the time derivative, there is no gravity, and full upstream weighting is used. The number of iterations for which the time step is increased is 40, the time step is increased by a factor of 1.2 at each iteration, the minimum time step size is 0.1 days, and the maximum time step size is 60 days. The geometry of the problem is 2-dimensional in the X-Y plane and the finite element coefficients are calculated during the run and not saved.

    ctrl
40
1
1.e-7
140
8
1
24
1
gmre
1.0
40
1
0.0
1.2
00
1.00
0.1
60.0

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