modelBaseProperties

Moist air base properties record

Information

This model computes thermodynamic properties of moist air from three independent (thermodynamic or/and numerical) state variables. Preferred numerical states are temperature T, density d and the reduced composition vector Xi, which contains the water mass fraction only. As an EOS the ideal gas law is used and associated restrictions apply. The model can also be used in the fog region, when moisture is present in its liquid state. However, it is assumed that the liquid water volume is negligible compared to that of the gas phase. Computation of thermal properties is based on property data of dry air and water (source: VDI-Wärmeatlas), respectively. Besides the standard thermodynamic variables absolute and relative humidity, x_water and phi, respectively, are given by the model. Upper case X denotes absolute humidity with respect to mass of moist air while absolute humidity with respect to mass of dry air only is denoted by a lower case x throughout the model. See package description for further information.

Components

TypeNameDefaultDescription
RealphiRelative humidity
MassFractionX_liquidMass fraction of liquid or solid water
MassFractionX_steamMass fraction of steam water
MassFractionX_airMass fraction of air
Densityd_satSteam water density of saturation boundary in kg_water/m3