2D Domains

A 2D simulation requires details about the 2D domain (the area to be modelled).

A ground elevation grid provides the underlying elevation data of the area; most commonly a Digital Terrain Model (DTM) or Digital Elevation Model (DEM) is used. Flood Modeller provides functionality to Load GIS datasets into the interface.

You can Create an active area to further increase efficiency. The calculations will be performed in this area. If not defined explicitly, the area covered by the DTM will be used.

Flood Modeller also provides functionality to Create a computational area. This will be split into grid cells, and the solver will determine if each grid cell is located inside or outside of the active area. Again, if not explicitly defined, the area covered by the DTM will be used.

Your licence must be sufficient to allow for the number of grid cells within the active area. If your licence is not sufficient, you may decrease the active area or increase the cell size to meet this requirement.

By default, your 2D model will use a globally constant roughness value, however it is also possible to define spatially varying roughness. Polygon shapefiles or raster grids may also be used to define varying roughness across the modelled area. Shapefiles must have an attribute called "value" (or “Descgroup” specifying land use type if Mastermap roughness data combined with a .fric text file).