The component shown on the upper right of a component icon number identifies the component model in the model window. After model initialization, these component numbers indicate the order of calculation during the iterations towards valid DP and OP operating points. The component numbering is automatic and 'dynamic' in a sense that they change after adding or deleting components in the model panel. Unlinked (non gas path, non control system etc.) components can be manually moved upwards or downwards in the sequence to change the calculation order. This may be necessary in some cases, for example:

•when determinate relations in schedulers are required to be evaluated before others

•additional output parameter component expressions use the result of other additional output parameters; then the latter should be moved before the former.

The component numbers are also shown in the (read-only) top right Calculation order field in the component data windows.

Because GSP internally uses the component numbers for ordering components in the iterations, the user cannot modify component numbers.

Note that if the component D string is empty, the component number is used instead to identify component parameters.