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FeOs - A Framework for Equations of State and Classical Density Functional Theory
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PhaseDiagram.binary_vle() Unable to Calculation Binary Mixtures without Critical Point #125

Closed ErichMace closed 1 year ago

ErichMace commented 1 year ago

When creating a binary phase diagram using PhaseDiagram.binary_vle() the current algorithm is not able to handle systems where a critical point does not exist. This would be the case, for example, for the mixture Ar-NH3 at 298.15 K.

image T=298K.zip

g-bauer commented 1 year ago

The binary VLE routine currently first tries to compute the pure-substance VLEs and - if a component is super-critical - will try to compute the critical point of the mixture which here fails.

Now, with the next version (0.4.0) it will be possible to create a PhaseDiagram object from multiple, "manually" constructed VLE's. You will be able to calculate VLE's using one of the available methods (tp-flash, dew- and bubble points) and put those into a PhaseDiagram. See #113. In the future, we may introduce a way to handle this issue within the binary_vle routine.

Note that, if you just want to generate a plot, you don't need the PhaseDiagram. You already can generate PhaseEquilibrium objects, e.g. for the pressure range you are interested in.

prehner commented 1 year ago

I think for these kind of "difficult" phase equilibria involving highly volatile components like argon, hydrogen, or helium, the solution presented in #113 is sufficient for now and therefore I'm closing this issue.