Recent changes to 286: Same simulation creating different results in different DWSIM versions

#286 Same simulation creating different results in different DWSIM versions

Daniel Medeiros — Wed, 24 Feb 2021 19:40:07 -0000

#286 Same simulation creating different results in different DWSIM versions

Leandro Favaretto — Wed, 24 Feb 2021 18:44:07 -0000

Still getting 0.0505844 as reported by DWSIM 6.4.0. Is there something I'm missing?

#286 Same simulation creating different results in different DWSIM versions

Daniel Medeiros — Wed, 24 Feb 2021 14:09:13 -0000

You should be using the GitHub issues section, I'll update the links. https://github.com/DanWBR/dwsim6/issues

#286 Same simulation creating different results in different DWSIM versions

Leandro Favaretto — Wed, 24 Feb 2021 13:50:54 -0000

Excellent, the 0,023 difference may be from difference pure compound properties between the two softwares.
Thank you very much. Don't forget to add the 6.4 Milestone to the ticket system so we can select the correct milestone.

#286 Same simulation creating different results in different DWSIM versions

Daniel Medeiros — Wed, 24 Feb 2021 13:28:31 -0000

v6.4.4 to be released today will give you 0.0034.

#286 Same simulation creating different results in different DWSIM versions

Leandro Favaretto — Wed, 24 Feb 2021 13:17:45 -0000

0,00106176202371422 according to Aspen Plus. Have you been able to see the difference in your computer or is it my pc only?

#286 Same simulation creating different results in different DWSIM versions

Daniel Medeiros — Wed, 24 Feb 2021 13:13:06 -0000

What is the expected vapor fraction in 6? 0.0034?

Same simulation creating different results in different DWSIM versions

Leandro Favaretto — Wed, 24 Feb 2021 03:12:19 -0000

Hello Daniel. Try to calculate the flowsheet in the attached simulation. In DWSIM 6.4.0, it calculates mass flow for the vapor stream exiting the conversion reactor. In DWSIM 6.4.3 it doesn't. This is a reproduction from a ASPEN PLUS file, and it is expected that stream 6 should be a vapour-liquid mixture, as reported by DWSIM 6.4.0, not a pure liquid stream, as reported by 6.4.3. Took a look at the changelog and have no idea what change could have created this inconsistency between versions. The matter of the fact is that an older DWSIM versino is producing a result that is better than an newer DWSIM version.
PS: Several user-created compounds have been added to this simulation, most of them imported directly from online sources. I do believe that the error in version 6.4.3 is not caused by these coumpounds as one might think, since 6.4.0 handled the VLE "fine" (takes a long time to complete but it does complete"). Maybe the conversion reactor in 6.4.3 is not flashing?
PS2: Funny enough, the mass flow of the product streams in both simulations is different, even though reaction kinetics are setted to "mixture" phase (therefore the existence of a vapour or liquid phase should not matter).