How does Aspen Property calculate the enthalpy of refrigerants? !
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Calculate the enthalpy value of the refrigerant R22 (CHCLF2) using Aspen Property. The results are shown in the figure. The boiling point of CHCLF2 is -40 degrees (1 atm), but why is there no sudden change in enthalpy at this point in my simulations? ! Please give me some advice!
The sudden change in enthalpy is the latent heat; just subtract the value for the liquid phase from that of the gas phase.
Looking at the diagram here, there don’t seem to be any mutations!
The line above is the vapor phase line, and the line below is the liquid phase line; the difference between them is the latent heat.
Take a look; the graph below shows the enthalpy values generated by HTRI. I’m not sure why Aspen represents the enthalpy values in this way.
And from Aspen’s graph, it’s really impossible to detect any significant changes in enthalpy! At a boiling point of -41 degrees, there isn’t really any significant change!
In A+, you choose gas and liquid; at equilibrium, the enthalpy values of the gas and liquid are calculated separately. For example, if the gas phase fraction is 0.5 at any temperature, then there are two lines. In the subsequent diagrams, what you define is pure liquid or pure gas.
For this refrigerant, at 1 bar, it remains in a gaseous state above -41 degrees; I don’t understand why there would be a liquid phase fraction !