GenCade 2.0 Model Control Dialog

The Gencade Model Control dialog is used to set beach conditions, lateral boundary conditions and general simulation options. This document highlights the more commonly used options. Refer to the GenCade web site for a more detailed description of how these parameters affect the model results.

This dialog has been updated for use with SMS 13.3 and the new GenCade interface. New items added are in red.

Note: At the bottom of each tab is a note shown in red that tells the user whether they are using Imperial (feet and yards) or Metric values for most fields. This determination is made based on the SMS Display Projection.

Model Setup Tab

GenCade Model Control dialog showing the Model Setup tab

The following parameters are specified in the model setup tab:

• Simulation
  • Title – Title of simulation run.
  • Full print output – Path and name of printed output file.
• Computational Time
  • Start Date – Simulation start date.
  • End Date – Simulation end date.
  • Time Step – Model time step in hours.
  • Recording Time Step – Recorded model time step in hours.
• Print Dates – Dates to save simulated shoreline. Use the Add button to create dates and the Remove button to delete any unwanted dates.
• Grid Information – static information about the GenCade grid including number of cells, grid angle, and length of 1d Grid.

Beach Setup Tab

GenCade Model Control dialog showing the Beach Setup tab

The following parameters are specified in the beach setup tab:

• Sand and Beach Data
  • Effective Grain Size – Medium sediment grain size in millimeters.
  • Average Berm Height – In feet or meters.
  • Closure Depth – In feet or meters.
  • Regional Sea Level Change in mm/year.
  • Regional Subsidence in mm/year.
  • Beach Slope.
• Longshore Sand Transport Calibration Coefficients
  • K1 – Range should be 0.1 < K1 <1
  • K2 – Range should be 0.5(K1) < K2 < 1.5(K1)
  • KTIDE – longshore transport coefficient for tide current.

Seaward BC Tab

GenCade Model Control dialog showing the Seaward BC tab

The following parameters are specified in the seaward boundary condition tab:

• Input Wave Adjustments – This section contains the following options:
  • Height Amplification Factor
  • Angle Amplification Factor
  • Angle Offset
• Wave Components to Apply – option is always "Primary (1)".
• Number of Cells in Offshore contour Smoothing Window – Default value is 11, but it is suggested that this be and odd number in the range between 11 and 101. If an even number is entered, GenCade will change to the next smaller odd value.

Lateral BC Tab

GenCade Model Control dialog showing the Lateral BC tab

The following parameters are specified in the lateral boundary condition tab for the left and right lateral boundary condition:

• Type – Determines one of three boundary types:
  • "Pinned" – Boundary will not move from the initial shoreline position.
  • "Gated" – Bounded with a groin. Requires that a groin exist and must be located in cell 1.
    • Length of Groin from Shoreline to Seaward Tip
  • "Moving" – Represents the amount of shoreline change at a boundary over a specified period of time.
    • Shoreline Displacement Velocity – Shoreline can be displaced over one of the following options:
      • "Simulation Period"
      • "Day"
      • "Time Step"

Adaptive Time Steps Tab

GenCade Model Control dialog showing the Adaptive Time Steps tab

The following parameters are specified in the adaptive time steps tab:

• Enable adaptive time steps – If turned on, allows the option to use the default values or set custom values.
• Once enabled, the following 5 values will have defaults. They can be changed based on user preference.
  • Threshold minimum
  • Threshold maximum
  • Number of days stable
  • Stability minimum
  • Stability maximum