ISIS 2D Quick Start Guide - Halcrow

ISIS 2D Quick Start Guide
How to Run an ISIS 2D 1D - 2D Linked Model
This Chapter illustrates an example of running an existing linked ISIS 1D and 2D model using the ISIS
2D Interface Tool. ISIS 1D-2D linked models combine the advantages of 1D modelling in the channel
and 2D floodplain modelling. In a linked model, the 2D model will represent complex flow paths and
1D river model will represent channel conveyance and the hydraulic structures in a river. Being able to
link models, you can now reuse your 1D channel models and let ISIS 1D do what it is best at
(modelling of channel flow and flow through various structures) and let ISIS 2D show its strength at
representing out of bank flows on the floodplain.
Running an existing ISIS 1D-2D model using the ISIS 2D Interface Tool
Basic information about the files needed for the ISIS 2D simulation
As mentioned in Chapter 1 "Starting ISIS 2D and Basic Concepts", ISIS 2D simulation requires several
files. Figure 1 (below) shows the domain extents (computational area) of this model as well as some
other input files which are needed for starting an ISIS 2D simulation. The example files used for this
Chapter are the Site 1 model files located in the folder C:\isis\data\examples\ISIS 2D\Site 1 (the
location will vary if ISIS is installed somewhere else). The files shown in Figure 1 are located in this
folder as well.
Figure 1. Representation of the main components of a 1D-2D linked model
On Figure 1 above the polygon marked by points (active area) is the ISIS 2D active area; alongside
the 2D active area there is a polyline (link line) showing the locations where the 1D and 2D models
are linked.
The active area shapefile and the link line shapefile have already been prepared. These files are
River_Active_Area[.shp,.dbf,.shx] and Link [.shp,.dbf,.shx] respectively. Figure 1 also shows the river
sections and the river centre line, which are not currently in any of the shapefiles provided, however
they represent the cross sections from Linked1D2D.ief file located in C:\isis\data\examples\ISIS
2D\Site 1\ISIS (The location will vary if ISIS is installed somewhere else). Please note Linked1D2D.ief
file is not a georeferenced model and therefore it is not possible to create a shapefile with the river
13