Solution Control Card Syntax (EOR-BO)

Character string (e.g., van Genuchten, porosity, m^3/s, Roe Superbee)

Integer (no alpha characters, special characters, or punctuation) (e.g., 1, 32, 195634)

Real (decimal points and exponential notation allowed) (e.g., 0, 0.0, 1.e-12, 1.E+3, 2.345)

Keyword (exact formatting required) (e.g., file, ~Solution Control Card, binary file)

Choose one Execution Mode Option

Normal Option

Normal,

Restart Option with Default Restart File (i.e., restart)

Restart,

Restart Option with Specified Restart Filename

Restart File,Restart Filename,

Operational Mode Keyword Modifiers

w/Transport - indicates solute transport

w/ECKEChem - indicates reactive transport

Repeat for each execution time period

Choose One

Choose one time-step reduction option

Four Successive Time Step Reductions before Execution Stop

Initial Time,Unit(s),Final Time,Unit(s),Initial Time Step,Units,Maximum Time Step,Units,Time Step Acceleration Factor,Maximum number of Newton-Raphson iterations per time step,Convergence Criterion,

Time Step Reductions to Minimum Time Step before Execution Stop

Initial Time,Unit(s),Final Time,Unit(s),Initial Time Step,Units,Maximum Time Step,Units,Time Step Acceleration Factor,Maximum number of Newton-Raphson iterations per time step,Convergence Criterion,Minimum Time Step,Units,Time Step Reduction Factor,

Execution Time periods

Execution periods refer to a period of simulation time. STOMP-W allows the user to specify a single or multiple execution periods. For each execution period, the user can control the initial time step, maximum time step, time step acceleration factor, maximum number of Newton-Raphson iterations, and convergence criterion independently.

Initial time

Execution Time Parameters

Recommended values for the Time Step Acceleration Factor, Maximum Number of Newton-Raphson Iterations, and Convergence Criterion are 1.25, 8, and 1.e-06, respectively. Except under special circumstances, it is not recommended to change the value for the Convergence Criterion from its recommended value. This value has proven through numerous applications to achieve a good balance between accuracy and execution speed.  

Execution Time Step Controls

Two additional solution controls can be specified for each Execution Period input line: 1) the minimum time step, and 2) the time-step cut factor.  These optional solution controls must be specified together.  The minimum-time-step parameter sets the minimum time step for an execution period.  Without this control, STOMP-W quits after four time-step reductions.  Cyclic injection well schedules can yield simulations that execute with large time steps during steady injection periods, but require small time steps during the injection startup.  The minimum-time-step parameter allows the code to cut the time step to the minimum value before quitting.  The time-step cut factor is set to 0.2 by default, which means that time steps are cut to 20% of their value when a convergence failure occurs. Execution performance can be improved for some simulations by altering this factor.

Zero Time Step Simuations

Repeat for the Number of Interfacial Averaging Variables

Specifying Interfacial Averaging Schemes

Field variables, which include physical, thermodynamic, and hydrologic properties, are defined in the finite-difference formulation at the node centers.  Conversely, flux variables are defined at node interfaces.  Computation of flux variables requires knowledge of field variables at node interfaces.  Values of flux variables at node interfaces are evaluated by averaging the field values for the two nodes adjoining an interfacial surface.  Interfacial averaging schemes may be declared individually for each field variable through the Interfacial Averaging Variables input.