Parallel computing of DWSIM and multiple flowsheets

[Hugo Brunner]

Hello,

For a project, I have to control DWSIM through Python to perform optimization. In order to compute the objective function, I have to simulate a process (an organic Rankine cycle with a recuperator with two recycles) for every hour of year (so 8760 points) and as you can see on the attached picture, it takes 4 to 5 seconds (it can even go to 7-8) so it will take few hours (roughly between 10h to 20h) to compute a year. As it is an optimization, the objective function will be called many times.

I wanted to know how I can speed up the convergence of the flowsheet ? I saw on DWSIM a checkbox called parallel, but I didn't see the difference in time with and without it.

And how to know if the solver (through Python) is in parallel mode with that command: Settings.SolverMode = 0 (with a special value instead of 0 ?) ?

My last question is about solving multiple flowsheets. Is it possible to solve multiple flowsheet with the same Python script (by giving different names with flowsheet_name = interf.LoadFlowsheet(path)) ?

Thank you in advance and have a good day,

[Daniel Medeiros]

Hi Hugo,

DWSIM is not yet ready for efficient parallel flowsheet solving, it will come in a future release. For now you will need to create multiple automation instances so each flowsheet runs in a separate memory space.

Regards,
Daniel

[Hugo Brunner]

Thank you a lot for your answer.

[Simulate 365]

Hi Hugo,

running flowsheets in parallel can be done using our Multivariate Sensitivity Study (MSS).

It works for DWSIM open-source and DWSIM Pro flowsheets, and it is free to use.

We have 2 "small" agents ready for your test. Once you are ready to run the study, drop us a line at https://simulate365.com/private-support/ , and we will switch to more agents and faster virtual machines.

You find our MSS here: https://simulate365.com/mss

Best,
Armin

[Hugo Brunner]

Hello Daniel,

I have another question that I found while playing with the DWSIM Python API. I found that when I comment the following line the code is much faster (like 5s to 2.5s), is it something that you could recommend ?

errors = b.CalculateFlowsheet2(flowsheet)

Thank you in advance and have a good day,