What is deviation enthalpy? Deviation entropy?
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I would like to ask everyone, what is deviation enthalpy? Deviation entropy? . . . . :handshake
You mean the residual property, right? It indicates the deviation from the ideal state.
Deviation enthalpy refers to the difference between the molar thermodynamic properties under the operating conditions (temperature, pressure) and those of an ideal gas at the same temperature but under a specified pressure p0. It is slightly different from the definition of residual properties. The residual property refers to the difference between the properties of a real fluid at the same temperature and pressure and those of an ideal gas at the same temperature and pressure. If p0 is equal to the operating pressure, then they are consistent; otherwise, there is a difference. The deviation in enthalpy depends on the choice of p0, but as long as p0 remains constant, the calculated change in enthalpy will not be affected by that choice. Aspen Plus uses deviation functions, while most thermodynamics textbooks in China discuss residual properties.