2D Simulations - Options Sub-tab

The Options tab allows initial conditions to be set for your simulation and contains details on the 2D solver to be used. The default condition is “Zero depth”; this assumes conditions are dry before the simulation runs.

To define initial conditions for your simulation, select the Type from the drop-down list. Options are:

(i) Global Water Level

(ii) Global Depth

(iii) Elevation File

(iv) Depth File

Global initial conditions (i.e. selection of “global water level” or “global depth”) require a value in metres to be specified in the Value field. Spatially varying initial conditions require a grid of water levels (selection of “Elevation file”) or depths (“Depth file”) covering all or part of the active area. In these instances, a file in ASC format containing this data is required. The filename can be entered directly into the Filename field or browsed to via standard windows file explorer.

Note that there are certain situations (certain geometries, for example) where dry conditions may cause instabilities in the simulation, so adding a water level/depth (globally or to specific areas) would stabilize the model.

2D solver to be used for the simulation can be selected from the Scheme drop-down list. The options are:

(i) ADI (default)

(ii) TVD

(iii) FAST

(iv) FAST Dynamic (FAST with time stepping)

The Precision setting will default as “Single” for all solver options, however you can change to double precision (using the drop-down box) if required.

Each of the solvers have various advanced parameters associated with them. These can be left set to their default values and your model should still run. However, in some cases, adjusting these parameters can enhance your model performance or speed up simulation times. Explanations of the parameters available with each solver are provided on the Advanced Parameters page. The Reset All to Defaults button can be used to reset all parameters to their default settings at any time.