Author Topic: Miture Grand canonical MC Fugacity  (Read 375 times)

Christopher

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Miture Grand canonical MC Fugacity
« on: December 18, 2020, 06:51:24 PM »
Dear RASPA fellows,

I want to do a Simulation in the Grand canonical ensemble in a COF. So the thermodynamic state is already chosen and I want to specify a fugacity coefficient that I calculated with PC-SAFT EOS.

The coefficient is already calculated in a mixture let's say 0.8 Molfrac methane and 0.2 Molfrac butane.

How do i correctly put in all necessary things. I think need:
ExternalPressure
FugacityCoefficient
MolFraction
IdealGasRosenbluthweight (for butane while methane is 1.)

Why do I have to specify the molfrac? Is this input fine now?
Best Christopher

Christopher

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Re: Miture Grand canonical MC Fugacity
« Reply #1 on: December 21, 2020, 02:48:45 PM »
I just solved my problem.

When entering a fugacity coefficient the Molfraction still has to be specified otherwise raspa uses default values and sets them to equimolar fractions. I thougt that the molefraction is already represented in the fugacity coefficient but since the reservoir is an ideal gas this should not be the case. Anyway keep in mind to specify Molfractions when simulated mixture in GCMC simulation is not equimolar.

best Christopher

David Dubbeldam

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Re: Miture Grand canonical MC Fugacity
« Reply #2 on: December 23, 2020, 07:35:52 PM »
See the example: Non-Basic/Adsorption_of_Binary_mixture_CO2_CH4_in_IRMOF-1
You specify total pressure and mol-fractions. Partial fugacities are computed and written to the output-file.


ExternalTemperature 300.0
ExternalPressure  10e5

Component 0 MoleculeName               CO2
            MolFraction                0.25

Component 1 MoleculeName               methane
            MolFraction                0.75