I'm having a bit of a problem with HYSYS. For example, based on the literature I'd expect water entropy at 0.1MPa and 800C to be around 235.7 J/(mol.K), but HYSYS gives me 220.8 J/(mol.K). Does anyone know why HYSYS entropy numbers are like this?
It seems that for all temperatures the entropy that HYSYS gives me are a certain amount higher than what I expect them to be. For example, for water it's around 15 J/mol.K.
I'm also wondering why in HYSYS entropy goes to 0 at -120C instead of -273C which is 0K. At around 0K HYSYS actually gives me astronomically large numbers.