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Solving DFTProfile for binary mixture with x1 = 1 results in singular matrix #39
Description
parameters = PcSaftParameters.from_json(
['toluene', 'acetone'],
'../parameters/pcsaft/loetgeringlin2018.json'
)
pcsaft = HelmholtzEnergyFunctional.pcsaft(parameters)
vle = PhaseDiagram.binary_vle(pcsaft, 300 * KELVIN, 251)
gamma = [PlanarInterface.from_tanh(pe, 1024, 100 * ANGSTROM, 500 * KELVIN).solve().surface_tension() for pe in vle.states]results in RuntimeError: The matrix appears to be singular. for both end-points (pure substances) of the phase diagram.
The above functionality can be done with a SurfaceTensionDiagram but would it be helpful to handle PhaseEquilibrium inputs for mixtures with x=1?
Activity
prehner commentedon Aug 2, 2022
The density solver cannot handle components with x=0 because their total chemical potential diverges. Even though a physical solution exists, it cannot be found because the code does not cancel out the diverging ideal gas contributions.
Some thoughts:
PhaseEquilibriums between different component sets could be useful (i.e. add components with n=0 or remove all components where n=0)prehner commentedon Dec 4, 2022
This problem is solved in #60. However, any solver with
log=Truewill still not converge as it will inevitably call log(0). So a solver has to be passed explicitly. In this case bothand
converge.