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[82ghost82]

Good morning all,
I have to build a DME Mollier diagram; I have a copy of water Mollier diagram, so before build the DME one I tried to build the water one to compare results:
in my water Mollier enthalpy goes from 2200 to 4200 kJ/kg;
I tried to find enthalpy of water in aspen so in Aspen I choose "phase=vapor","property=H (enthalpy for a pure component)", choose P=1 bar and T=175°C but the result is -13141,49 kJ/kg
What's wrong??
How to build the Mollier?

Thank you,
Daniele

[joerd]

The discrepancy you see has to do with the choice of reference state for your enthalpy. I don't know what your example uses, but Aspen Plus uses the enthalpy of formation at 0 C and atmospheric pressure, I believe.