Reply To: Reference Enthalpy Values in Material Properties database Ansys Fluent

[jcooper]

Hi:

These are the real formation enthalpies.  Watch out for the units….

The standard enthalpy of formation of water at 25 C and 1 atm  is -285.8 kJ/mol. This is because the reaction (of O2 and H2) that creates a molecule of water releases heat, so water actually ends up at a lower energy state than its components. 

The units of the Fluent enthalpy of formation are in [J/kgmol], however, so we must convert:

Converting the units: 

Hf = -285.8 kJ/mol  * 1000 kJ/J  *1000 mol/kmol = -2.85e+08 J/kmol

 

Regards,

Judy