I would find it convenient at times to specify a mass or mole flow out one port of a splitter. This would allow me to maintain some specified reaction products/energy on the specified mass flow. Then the other port would just follow the mass balance.
As it stands, upstream changes to the inlet stream flow rate impact my reactor.
Splitter Unit Op Enhancement Request
Moderator: jasper
Re: Splitter Unit Op Enhancement Request
One way would be to control the split factor by measuring the flow rate on the desired product stream. This requires:
- the splitter
- exposing the splitter's split fraction as a virtual information inlet port
- a measure unit in the splitter's product
- exposing the flow rate from the measure unit
- a controller
- connect the controlled variable of the controller with an information stream to the split fraction
- connect the measured variable of the measure unit with an information stream to the controller
- set the set point of the controller to the desired flow rate
- provide an initial guess for the split factor on the controlled information stream
You could wrap all of this up in an embedded flowsheet to make it a single unit operation.
Another way to do it is to use for example an Excel, Matlab or Scilab unit operation. Or write one from scratch.
- the splitter
- exposing the splitter's split fraction as a virtual information inlet port
- a measure unit in the splitter's product
- exposing the flow rate from the measure unit
- a controller
- connect the controlled variable of the controller with an information stream to the split fraction
- connect the measured variable of the measure unit with an information stream to the controller
- set the set point of the controller to the desired flow rate
- provide an initial guess for the split factor on the controlled information stream
You could wrap all of this up in an embedded flowsheet to make it a single unit operation.
Another way to do it is to use for example an Excel, Matlab or Scilab unit operation. Or write one from scratch.
Re: Splitter Unit Op Enhancement Request
If this is to maintain the flow rate in a recycle, check out the make-up mixer. In this case the split fraction of the purge can simply be the desired split rate and the feed is variable (from a surplus feed, the remainder of which is purged)
Re: Splitter Unit Op Enhancement Request
Thanks for the ideas.
I am actually splitting off some feedstock for combustion and want to maintain the Heat Release Rate as I vary feedstock flow rate to understand how the rest of the process is optimized.
I've yet to successfully implement a feedback controller in COCO, but I gave it a shot with your guidance. In the end I went back to off-line calculation of the split ratio after having no luck getting convergence.
I am actually splitting off some feedstock for combustion and want to maintain the Heat Release Rate as I vary feedstock flow rate to understand how the rest of the process is optimized.
I've yet to successfully implement a feedback controller in COCO, but I gave it a shot with your guidance. In the end I went back to off-line calculation of the split ratio after having no luck getting convergence.
Re: Splitter Unit Op Enhancement Request
Is there any way you can send me the fsd (or a simplified version thereof) so that I can have a look?