At the 3rd CAPE-OPEN European Conference, Ensheng ZHAO and Murugesh PALANISAMY from Honeywell Inc. made a presentation in which they showed the following video to demonstrate how a CAPE-OPEN Unit Operation could be plugged into UniSim Design and run.
The specific CAPE-OPEN Unit Operation they used for that demonstration is one exported from gPROMS.
The video starts with a view of gPROMS Model Builder 3.0.0 in which a model of a separator vessel has been developed.
A Separator Vessel is mostly just another name for a flash drum, separating an inlet stream into a liquid and a vapor stream. Indeed the objective of this model is to replicate the flash tank available already in UniSim Design.
Through CAPE-OPEN interfaces, the model accesses the thermodynamic server in UniSim Design especially to perform a flash where temperature and pressure are specified. The video briefly shows the model as coded in gPROMS. Then the video shows that the liquid percentage is set as a parameter for the Unit Operation and made a Public Unit Parameter (PUP) that can be accessed from the PME (here UniSim Design) to specify the flash.
Next the video shows how the “Export to CAPE-OPEN” feature works in gPROMS. Rather straightforward, giving even the possibility to encrypt with a password the input file containing the description of the gPROMS model.
The video then moves onto UniSim Design R360 being launched and showing a flowsheet, the well-known HDA process case which is often used for demos of any kind. Block V-100 is a flash tank modelled with a separator from UniSim Design library. Its specification is shown as well as the streams going in and coming out from that block.
The simulation is then put on hold and the block is deleted.
A new Unit Operation, a CAPE-OPEN Unit Operation, is inserted to replace it, selecting the g0_CAPE-OPEN unit operation from the list of CAPE-OPEN Unit Operations available on the machine used for the recording. The initialization of this Unit Operation asks for the input file to be used. The previously recorded input file of the vessel separator is loaded into g0_CAPE-OPEN.
Next connections are made between inlet and outlet ports of the unit operation and streams available in the Flowsheet (the streams previously linked to the UniSim Design flash tank. The video also shows that UniSim Design has access to the Public Unit Parameter representing the liquid percentage to be set for the flash.The value of that parameter is then modified so that it is equal to the one that was used for the UniSim design flash tank, i.e. 50%. The video shows that it is also possible to access a Graphical User Interface of the g0_CAPE-OPEN Unit Operation. This GUI is part of g0_CAPE-OPEN and has been developed by Process Systems Enterprise as part of g0_CAPE-OPEN. Prior to calculation of the Unit Operation (the simulation is still on hold), the outlet streams are not known within the Unit Operation as briefly shown through the video.
Next the calculation mode of UniSim Design is put back on and we see that the g0_CAPE-OPEN Unit Operation is immediately solved. The GUI of the Unit Operation is then accessed in order to show that the information on the outlet streams has now been populated.