Error in NIST enthalpy equation

[AlexNoring]

The equation for enthalpy in idaes.generic_models.properties.core.pure.NIST is not consistent with the equation posted at NIST webbook. The reference temperatures need to be removed.

[andrewlee94]

PR #291 contains a temporary workaround for this issue which will need to be removed once this issue is fixed.

[jghouse88]

@anujad95 May be relevant for you as well.

[adowling2]

@agarciadiego Any thoughts?

[andrewlee94]

@agarciadiego I have been working on fixing this and have most of it up and running now, however there is one test hat is still failing. It is test_temp_swing in test_CO2_H2O_Ideal_VLE.py and I wanted to check to see if the expected heat duty data was verification data from an external source, or was just a compiled list of results you got from running the model - i.e. should I be concerned that these values have changed.

[agarciadiego]

@andrewlee94 I didn't create the 'CO2_H2O_Ideal_VLE.py' file. I haven't used the equation for enthalpy in idaes.generic_models.properties.core.pure.NIST for my examples as I could not find all the parameters for all the species I needed, so I used different versions of RPP and Perry.

[andrewlee94]

@anujad95 It appears the failing test is one of yours - do you know where the heat duty numbers came from in test_temp_swing in test_CO2_H2O_Ideal_VLE.py? The values changed after I corrected the NIST correlation, so I want to know if these values are from an external source or not (i.e. whether I should be concerned that the value changed or not).

[anujad95]

@andrewlee94 The heat duty values are based on CO2_H2O_Ideal_VLE.py itself. I need to check if the coefficient 'H' in the configuration dictionary needs to be modified according to your corrections in the NIST correlation.

[andrewlee94]

Fixed in #223.