Equations for IF97
- Last UpdatedAug 13, 2024
- 1 minute read
The model details of the IF97 calculations, described in the PDF from IAPWS1, are very verbose and are not represented here. However, these details are not necessary to use IF97 as they are encapsulated within the steam Fluid State model in AVEVA Process Simulation.
The IAPWS Industrial Steam Tables are suitable for calculating the following properties for steam and water, given a temperature and a pressure:
|
Variable |
Description |
|
V |
Specific Volume |
|
H |
Specific enthalpy |
|
U |
Specific internal energy |
|
S |
Specific entropy |
|
m |
Dynamic viscosity |
|
Ps |
Saturation pressure as a function of temperature |
|
Ts |
Saturation temperature as a function of pressure |
The steam Fluid State model uses the IAPWS internal energy and entropy datums, which state that, at the triple point (273.16 K, 611.657 Pa), the (saturated) specific liquid internal energy and the specific entropy are set equal to zero. This results in an enthalpy of saturated liquid at triple point of 0.611783 J/kg.