Table of Contents
The Solution Controls dialog allows the user to specify all aspects that will be used by TOUGH in solving the problem. To set these controls, select Analysis->Solution Controls... or 
to open the Solution Controls dialog.
Select the Times tab, Figure 11.1. This dialog is used to input all data related to solution times and time step control.
Start Time - The start of the analysis. In most cases this will be 0.0.
End Time - The end time of the analysis. Usually specified, but can be set to infinite and then solution will run for the Max Num Time Steps
Time Step - User control of the time steps. If Automatic Time Step Adjustment is enabled (recommended), this is the initial time step used in the analysis. The user can also specify a table of time steps for the solution. If a list of time steps is given, the last time step will be used until the End Time is reached. If the user has selected to define the time steps in a table and enabled Automatic Time Step Adjustment, the specified table of time steps is used first, with automatic adjustment after if the number of solution time steps exceeds the number of time steps in the list.
Max Num Time Steps - The maximum number of time steps for the solution. If this number is exceeded, the analysis ends.
Max CPU Time - A control to limit the maximum CPU time used in the analysis. If this number is exceeded, the analysis ends
Max Iterations per Step - The maximum number of iterations for a time step. If exceeded and Automatic Time Step Adjustment is enabled, then time step will be reduced.
Automatic Time Step Adjustment - If selected, the time step size will be automatically adjusted (recommended).
Max Time Step - Maximum time step that will be used when adjusting the time step.
Iter. to Double Time Step - If convergence is reached in this number of iterations, then time step size will be increased.
Reduction Factor - If convergence fails in Max Iterations per Step, then time step will be reduced by this factor.
Select the Solver tab, Figure 11.2. TOUGH provides conjugate gradient and direct solvers, with several options. The user can select the solution method and options for that method. Either the Preconditioned Bi-Conjugate Gradient (default) or Stabilized Bi-Conjugate Gradient methods are recommended.
Select the Weighting tab, Figure 11.3. These are advanced TOUGH2 options. For most users, the default values are appropriate. See the TOUGH2 manual for more detailed descriptions.
Select the Convergence tab, Figure 11.4. Advanced convergence options. In most cases, the user will not change these parameters.
Select the Options tab, Figure 11.5. Advance options. In most cases, these will not be changed by the user.
The Output Controls dialog allows the user to specify output options. To set these controls, select Analysis->Output Controls... or 
to open the Output Controls dialog, Figure 11.6.
Output Controls options include:
Print and Plot Every # Steps - Output will be written at the specified time step increment.
Additional Print and Plot Times - This opens a table in which you can give specific times at which output is desired.
Additional Output Data - Select fluxes and velocities to have the output data necessary to include flux arrows in the 3D plots. Selecting Primary Variables is usually only used for debugging purposes.
Additional Prinout - These options are usually only used for debugging purposes.