gPROMS ModelBuilder version 2.3.1

Figure 4.8 Additional information display
4.3.2.3 Topology connections and the gPROMS language
35
Topology tab
Each Unit on the Topology corresponds to a declaration of a Model instance. The Unit declarations are shown (and
can be edited) on the gPROMS language tab in the UNIT section
Each connection on the Topology corresponds to an equation that equates the two Ports 18 . Like the Unit
declarations, the equations are shown (and can be edited) on the gPROMS language tab in the TOPOLOGY section.
4.3.3 Hierarchical model construction
Most of the models in the gPROMS Process Model Library (PML) are primitive models – i.e. non-composite models.
However, in gPROMS there is no limitation with respect to the number of levels in the hierarchical model
decomposition: composite models with a defined topology can themselves be used to build even more complex
composite models (see for example the PML distillation column).
To use a composite model on the Topology tab of a higher level model the user must simply define the Interface for
the composite model (i.e. introduce an icon and add Ports) as described earlier in Section 4.2. The Ports of a
composite model appear on this Model’s own Topology tab: these can be connected to any other valid Port on the
topology as shown in Figure 4.9.
18 More explicitly gPROMS expands the Port definition to equate all the variables in the two Ports.