COFE Flowsheet Unit Operation

[nrgeng]

[jasper]

[jasper]

Unit parameter reports embedded in the flowsheet of course allow easy inspection of output parameters, as an alternative to information streams.

[nrgeng]

[jasper]

First, can you let me know how to reproduce a crash?

Second, I am not sure what you mean with Unit operation [Ports]. Can you send me an example?

Regarding a controller: it is not a classic unit operation in the sense that it takes and input and predicts an output. It adds different types of equations to the overall system, and as a result

- the system is no longer suitable for direct substitution, and only Newton like solvers can be used
- the stream that comes out of a controller must be a cut stream, hence it needs to be contained inside a recycle

I am not sure how you cut your flowsheet up: again, can you send me an example?

[nrgeng]

In response to your first request
COFE crashed for three different reasons on 06/17/14 with a complicated flowsheet that contained Flow Constraints and Controllers. Today using a simple flowsheet, COFE crashed only when I deleted an imported flowsheet then attempted to import the flowsheet again. This seems to work (crash) with any fsd file, but I am sending today's simple fsd file and two images of the crash screen for your viewing pleasure. Hope this helps with debugging.

[jasper]

I will need more info, as I cannot reproduce a crash just by opening your document, deleting the unit operation, inserting a new COFE unit operation and importing an (any) fsd file in there. Can you tell me which steps I need to perform exactly to obtain a crash?

Are you using the latest version of COFE?

[nrgeng]

I am reluctant to upgrade due to past problems incurred as a result of upgrading. Any method suggested to go back to the current working version if a problem develops? With hundreds of hours of time invested in developing working simulations, it takes a leap of faith for me to risk upgrading these days.

Current Versions:
COFE 2.6.0.21 (x86, 32-bit)
COUSCOUS 2.6.0.24 Mixer
COUSCOUS 2.6.0.21 COFE Flowsheet Unit Operation

I did not see anything in the Change Log (2.6.0.28) that would indicate a need to upgrade. Do you know of something?

PS. Have you considered placing the latest changes at the top rather than at the bottom of the Change Log?

[jasper]

You can just copy the entire COCO folder, and copy it back if you need to. All changes, except for COM object registration, are kept local to the COCO folder. COM object registration you can simply redo, but should not be necessary as nothing has changed (except Water, you may need to re-register that; lots of fixes there since 2.6.0.4).

This update may have fixed it:

COFE (2.6.0.27): corrections in phase sorting for 1.0 external thermodynamics (COFE Flowsheet Unit Operation)

Yes, I did consider it.

[nrgeng]

Updated with CUP successfully. No change. Same as before.
Load MAIN, Open SUB Unit GUI, Select All, Delete, Enter, [within existing open SUB Unit GUI] Import Existing Flowsheet {select SUB} Open ==> Crash.
Current Versions:
COFE 2.6.0.27 (x86, 32-bit)
COUSCOUS 2.6.0.28 Mixer
COUSCOUS 2.6.0.27 COFE Flowsheet Unit Operation