input variables

[thubelihle]

Hi. l notice l can't vary number of stages as an independent parameter using the COCO parametric study. Same applies for the heat exchanger outlet temperature can not be specified as an independent variable to vary on the parametric studies. Thanks

[jasper]

You can vary many things - but they have to be input parameters. To make the number of stages an input parameter, you have to tell ChemSep to do so.

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[jasper]

The heat exchanger outlet temperature is only an input parameter if the heat exchanger has Type = Temperature

[thubelihle]

Hi. l notice l can't vary number of stages as an independent parameter using the COCO parametric study. Same applies for the heat exchanger outlet temperature can not be specified as an independent variable to vary on the parametric studies. thanks. The bottoms flowrate is one of specifications and l exposed it as an input parameter, but does not converge using a controller

[thubelihle]

I even try to put a value of 0.6 for bottoms flowrate but l try to solve it automatically changes this value

[jasper]

[thubelihle]

It’s from Distillation design n control by Luyben 2nd edition example on chapter 3. Thanks

[thubelihle]

hi jasper, attached is the distillation column with a controller. it does not converge but looking at the specification, the set point is reached, but still it gives the error message . thank you for your help.

[jasper]

The same problem is present again - did you use your document or my corrected Luyben_edited as a starting point for this one?

[thubelihle]

yes l just did and l am facing the same issue. thank you, see attachment.