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A repository solely used for reporting issues with NIST REFPROP
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Ethylene Glycol - enthalpy model #359

Closed StephanThermo closed 3 years ago

StephanThermo commented 3 years ago

Which model is used for enthalpy calculations of ethylene glycol within refprop?

ianhbell commented 3 years ago

Do you mean neat ethylene glycol, or ethylene glycol + water? If the pure fluid, then the properties in REFPROP come from a (so-far unpublished) equation of state (EOS) developed by our colleagues. The reference to the equation of state is visible in the GUI under Substance->Fluid Information:

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StephanThermo commented 3 years ago

Thank you. One more question: Which model is used for binary mixtures of ethylene glycol and water? (enthalpy and density is of interest)

ianhbell commented 3 years ago

For ethylene glycol + water, the interaction parameters were fit by Eric Lemmon and myself. Otherwise, the model formulation for ethylene glycol + water is the same as in the GERG model: https://www.gerg.eu/wp-content/uploads/2019/10/TM15.pdf . The most accurate pure fluid EOS are used, along with interaction parameters to shape the thermodynamic surface.