User:Mburton/HydroGeoSphere Simulation Control

Many of the inputs required for a HydroGeoSphere simulation are configured in the Simulation Control, which is accessed by right-clicking on the simulation in the Project Explorer. The following is a list of parameters available in the Simulation Control dialog.

HydroGeoSphere Simulation Control dialog

General

• Description: this purpose of this textbox is to enter a description that will appear at the top of the .grok file.
• Transient flow: this checkbox adds a time-stepping, transient flow solution.
• Unsaturated: this checkbox adds a variably-saturated flow solution.
• Finite difference
  • Finite difference mode: uses the finite difference approach rather than default finite element method.
  • Control volume: uses the control-vlume finite difference approach instead of the default standard finite difference approach. This option results in a conservative scheme with better numerical stability than the default approach.
• Domains
  • Porous media: include the porous media domain. This option is always on.
  • Surface flow: includes the surface flow domain.
    • Dual nodes for surface flow: use the dual-node approach to define the discrete surface flow domain. This option is always on.
  • ET: includes the ET (evapotranspiration) domain.

Units

• Units: a dropdown menu that converts the default values into the specified system. It does not convert properties specified in any .grok, .mprops, etc. files.
  • Kilogram-metre-second
  • Kilogram-metre-minute
  • Kilogram-metre-hour
  • Kilogram-metre-day
  • Kilogram-metre-year
  • Kilogram-centimetre-second
  • Kilogram-centimetre-minute
  • Kilogram-centimetre-hour
  • Kilogram-centimetre-day
  • Kilogram-centimetre-year
• Gravitational acceleration: set a default gravitational acceleration value.

Saturated flow

• No fluid mass balance: this checkbox suppresses the calculation of fluid mass balance information, which is, by default, computed at each time step.
• Flow solver maximum iterations: maximum number of flow solver iterations, defaults to 2000.
• Flow solver convergence criteria: flow solver convergence tolerance.
• Flow solver detail: controls the level of detail of the solver performance. This defaults to 0-no information, but can also be set to 1-full information.

Variably saturated flow

• Upstream weighting factor
• Newton iteration parameters
  • Remove negative coefficients: forces negative inter-nodal conductance to zero.
  • No nodal flow check: turns off nodal flow check, which is on by default.
  • Nodal flow check tolerance
  • Underrelaxation factor: factor for the Newton iteration. This defaults to one, but can range from zero to one.

Time stepping

• General timestep settings
  • Initial time
  • Initial timestep
  • Maximum timestep
  • Minimum timestep
  • Time varying maximum timestep
  • Target times
  • Minimum timestep multiplier
  • Maximum timestep multiplier
  • Jacobian epsilon: the shift in the pressure head used to numerically compute the derivatives in the Jacobian matrix.
  • Minimum relaxation factor for convergence
  • Newton maximum iterations
  • Newton minimum iterations
  • Newton absolute convergence criteria
  • Newton residual convergence criteria
  • Newton maximum update for head
  • Newton maximum update for depth
  • Newton absolute maximum residual
  • Newton maximum residual increase
• Adaptive timestep settings
  • Head control: maximum allowed change in nodal head during any timestep.
  • Water depth control: maximum allowed change in surface water depth during any timestep.
  • Saturation control: maximum allowed change in nodal saturation during any timestep.
  • Newton iteration control: maximum allowed change in Newton-Raphson iterations during any timestep.

Output

• Output times: listed items are added to the current set of output times.

Zones

• Read porous media zones from file: import a data set containing the element zone numbers for the porous media domain.
• Read surface flow zones from file: import a data set containing the element zone numbers for the surface flow domain.
• Read ET zones from file: import a data set containing the element zone numbers for the ET domain.

Initial conditions

• Head
  • Initial head
  • Initial head depth to water table
  • Initial head surface elevation
  • Initial head from file: import an initial head value set from a file.
• Water depth
  • Initial water depth
  • Initial water depth from file: import an initial water depth value set from a file.