Vapour and liquid heat capacity constants have inconsistent units in PresetSpecies

[davidschlachter]

We need the units of heat capacities to be in J/mol with temperatures in K, since we take molar flow rates and perform calculations on a molar basis. I just changed the heat capacity values for water vapour (in da9a431), which were in J/mol, but gave a C_p/R value instead of C_p (values were taken from Table C1 in Smith & Van Ness — other values from that table will need to same adjustment). I noticed that some heat capacities given in other sources are in energy/mass instead of energy/mole, and some of this might be in our PresetSpecies as well!

We probably need to check all the heat capacity units, reference them, and make corrections as necessary!

[davidschlachter]

Some work on this:

• Return heat capacities in J/mol, instead of as (J/mol)/R 861c627
• Add test for water vapour heat capacity integration 1dc95e2
• Add test for pure species enthalpy change 92cb228

[davidschlachter]

On the other hand, 861c627 should probably be reversed to continue multiplying by R so we don't have to change all the constants (but still need to check all the units!)

[davidschlachter]

Here's the spreadsheet I used to convert the heat capacity constants:

Heat capacity coefficients.xlsx

I verified from comparison with the steam tables that the constants used in the book will return J/mol once multiplied by R.