The software can run out of memory to store temporary data, or it simply takes a very long time to run, when a complex modelling scenario is applied. The imported data node can assist here.
A 'complex' or large model could be defined as follows:-
- A large number of source and treatment nodes - more than 100 nodes;
- A long time series of data - greater than 20 years; and
- Short time step - 6 minutes.
Separating the model into smaller sub-catchment models and the results of each then imported back into a “full” model, which may simply be a group of imported data nodes.
If the initial model was shown to be too complex (note images on this page are simplified for the purposes of this explanation),
Figure 1 Potential Subcatchments
With the above, 3 logical subcatchments would be appropriate. Each of these would then be set up as individual subcatchment models (as per the example in the multiple rainfall locations tip) and the data exported out into a final “full” model. Once again, using the above model as an example, this would look like the model shown below.