Modelica.Media.Air.MoistAir

Air: Moist air model (190 ... 647 K)

Information

Thermodynamic Model

This package provides a full thermodynamic model of moist air including the fog region and temperatures below zero degC. The governing assumptions in this model are:

• the perfect gas law applies
• water volume other than that of steam is neglected

All extensive properties are expressed in terms of the total mass in order to comply with other media in this library. However, for moist air it is rather common to express the absolute humidity in terms of mass of dry air only, which has advantages when working with charts. In addition, care must be taken, when working with mass fractions with respect to total mass, that all properties refer to the same water content when being used in mathematical operations (which is always the case if based on dry air only). Therefore two absolute humidities are computed in the BaseProperties model: X denotes the absolute humidity in terms of the total mass while x denotes the absolute humidity per unit mass of dry air. In addition, the relative humidity phi is also computed.

At the triple point temperature of water of 0.01 °C or 273.16 K and a relative humidity greater than 1 fog may be present as liquid and as ice resulting in a specific enthalpy somewhere between those of the two isotherms for solid and liquid fog, respectively. For numerical reasons a coexisting mixture of 50% solid and 50% liquid fog is assumed in the fog region at the triple point in this model.

Range of validity

From the assumptions mentioned above it follows that the pressure should be in the region around atmospheric conditions or below (a few bars may still be fine though). Additionally a very high water content at low temperatures would yield incorrect densities, because the volume of the liquid or solid phase would not be negligible anymore. The model does not provide information on limits for water drop size in the fog region or transport information for the actual condensation or evaporation process in combination with surfaces. All excess water which is not in its vapour state is assumed to be still present in the air regarding its energy but not in terms of its spatial extent.

The thermodynamic model may be used for temperatures ranging from 190 ... 647 K. This holds for all functions unless otherwise stated in their description. However, although the model works at temperatures above the saturation temperature it is questionable to use the term "relative humidity" in this region. Please note, that although several functions compute pure water properties, they are designed to be used within the moist air medium model where properties are dominated by air and steam in their vapor states, and not for pure liquid water applications.

Transport Properties

Several additional functions that are not needed to describe the thermodynamic system, but are required to model transport processes, like heat and mass transfer, may be called. They usually neglect the moisture influence unless otherwise stated.

Application

The model's main area of application is all processes that involve moist air cooling under near atmospheric pressure with possible moisture condensation. This is the case in all domestic and industrial air conditioning applications. Another large domain of moist air applications covers all processes that deal with dehydration of bulk material using air as a transport medium. Engineering tasks involving moist air are often performed (or at least visualized) by using charts that contain all relevant thermodynamic data for a moist air system. These so called psychrometric charts can be generated from the medium properties in this package. The model PsychrometricData may be used for this purpose in order to obtain data for figures like those below (the plotting itself is not part of the model though).

Legend: blue - constant specific enthalpy, red - constant temperature, black - constant relative humidity

Extends from Interfaces.PartialCondensingGases (Base class for mixtures of condensing and non-condensing gases).

Package Content

Name	Description
Water=1	Index of water (in substanceNames, massFractions X, etc.)
Air=2	Index of air (in substanceNames, massFractions X, etc.)
k_mair=steam.MM/dryair.MM	Ratio of molar weights
dryair=IdealGases.Common.SingleGasesData.Air
steam=IdealGases.Common.SingleGasesData.H2O
MMX={steam.MM,dryair.MM}	Molar masses of components
ThermodynamicState	ThermodynamicState record for moist air
BaseProperties	Moist air base properties record
setState_pTX	Return thermodynamic state as function of pressure p, temperature T and composition X
setState_phX	Return thermodynamic state as function of pressure p, specific enthalpy h and composition X
setState_dTX	Return thermodynamic state as function of density d, temperature T and composition X
setSmoothState	Return thermodynamic state so that it smoothly approximates: if x > 0 then state_a else state_b
Xsaturation	Return absolute humidity per unit mass of moist air at saturation as a function of the thermodynamic state record
xsaturation	Return absolute humidity per unit mass of dry air at saturation as a function of the thermodynamic state record
xsaturation_pT	Return absolute humidity per unit mass of dry air at saturation as a function of pressure p and temperature T
massFraction_pTphi	Return steam mass fraction as a function of relative humidity phi and temperature T
relativeHumidity_pTX	Return relative humidity as a function of pressure p, temperature T and composition X
relativeHumidity	Return relative humidity as a function of the thermodynamic state record
gasConstant	Return ideal gas constant as a function from thermodynamic state, only valid for phi<1
gasConstant_X	Return ideal gas constant as a function from composition X
saturationPressureLiquid	Return saturation pressure of water as a function of temperature T in the range of 273.16 to 647.096 K
saturationPressureLiquid_der	Derivative function for 'saturationPressureLiquid'
sublimationPressureIce	Return sublimation pressure of water as a function of temperature T between 190 and 273.16 K
sublimationPressureIce_der	Derivative function for 'sublimationPressureIce'
saturationPressure	Return saturation pressure of water as a function of temperature T between 190 and 647.096 K
saturationPressure_der	Derivative function for 'saturationPressure'
saturationTemperature	Return saturation temperature of water as a function of (partial) pressure p
enthalpyOfVaporization	Return enthalpy of vaporization of water as a function of temperature T, 273.16 to 647.096 K
HeatCapacityOfWater	Return specific heat capacity of water (liquid only) as a function of temperature T
enthalpyOfLiquid	Return enthalpy of liquid water as a function of temperature T(use enthalpyOfWater instead)
enthalpyOfGas	Return specific enthalpy of gas (air and steam) as a function of temperature T and composition X
enthalpyOfCondensingGas	Return specific enthalpy of steam as a function of temperature T
enthalpyOfNonCondensingGas	Return specific enthalpy of dry air as a function of temperature T
enthalpyOfWater	Computes specific enthalpy of water (solid/liquid) near atmospheric pressure from temperature T
enthalpyOfWater_der	Derivative function of enthalpyOfWater
pressure	Returns pressure of ideal gas as a function of the thermodynamic state record
temperature	Return temperature of ideal gas as a function of the thermodynamic state record
T_phX	Return temperature as a function of pressure p, specific enthalpy h and composition X
density	Returns density of ideal gas as a function of the thermodynamic state record
specificEnthalpy	Return specific enthalpy of moist air as a function of the thermodynamic state record
h_pTX	Return specific enthalpy of moist air as a function of pressure p, temperature T and composition X
h_pTX_der	Derivative function of h_pTX
isentropicExponent	Return isentropic exponent (only for gas fraction!)
isentropicEnthalpyApproximation	Approximate calculation of h_is from upstream properties, downstream pressure, gas part only
specificInternalEnergy	Return specific internal energy of moist air as a function of the thermodynamic state record
specificInternalEnergy_pTX	Return specific internal energy of moist air as a function of pressure p, temperature T and composition X
specificInternalEnergy_pTX_der	Derivative function for specificInternalEnergy_pTX
specificEntropy	Return specific entropy from thermodynamic state record, only valid for phi<1
specificGibbsEnergy	Return specific Gibbs energy as a function of the thermodynamic state record, only valid for phi<1
specificHelmholtzEnergy	Return specific Helmholtz energy as a function of the thermodynamic state record, only valid for phi<1
specificHeatCapacityCp	Return specific heat capacity at constant pressure as a function of the thermodynamic state record
specificHeatCapacityCv	Return specific heat capacity at constant volume as a function of the thermodynamic state record
dynamicViscosity	Return dynamic viscosity as a function of the thermodynamic state record, valid from 123.15 K to 1273.15 K
thermalConductivity	Return thermal conductivity as a function of the thermodynamic state record, valid from 123.15 K to 1273.15 K
velocityOfSound
isobaricExpansionCoefficient
isothermalCompressibility
density_derp_h
density_derh_p
density_derp_T
density_derT_p
density_derX
molarMass
T_psX	Return temperature as a function of pressure p, specific entropy s and composition X
setState_psX
s_pTX	Return specific entropy of moist air as a function of pressure p, temperature T and composition X (only valid for phi<1)
s_pTX_der	Return specific entropy of moist air as a function of pressure p, temperature T and composition X (only valid for phi<1)
isentropicEnthalpy	Isentropic enthalpy (only valid for phi<1)
Utilities	Utility functions
Inherited
fluidConstants	Constant data for the fluid
moleToMassFractions	Return mass fractions X from mole fractions
massToMoleFractions	Return mole fractions from mass fractions X
ThermoStates	Enumeration type for independent variables
mediumName="unusablePartialMedium"	Name of the medium
substanceNames={mediumName}	Names of the mixture substances. Set substanceNames={mediumName} if only one substance.
extraPropertiesNames=fill("", 0)	Names of the additional (extra) transported properties. Set extraPropertiesNames=fill("",0) if unused
singleState	= true, if u and d are not a function of pressure
reducedX=true	= true if medium contains the equation sum(X) = 1.0; set reducedX=true if only one substance (see docu for details)
fixedX=false	= true if medium contains the equation X = reference_X
reference_p=101325	Reference pressure of Medium: default 1 atmosphere
reference_T=298.15	Reference temperature of Medium: default 25 deg Celsius
reference_X=fill(1/nX, nX)	Default mass fractions of medium
p_default=101325	Default value for pressure of medium (for initialization)
T_default=Modelica.SIunits.Conversions.from_degC(20)	Default value for temperature of medium (for initialization)
h_default=specificEnthalpy_pTX(p_default, T_default, X_default)	Default value for specific enthalpy of medium (for initialization)
X_default=reference_X	Default value for mass fractions of medium (for initialization)
nS=size(substanceNames, 1)	Number of substances
nX=nS	Number of mass fractions
nXi=if fixedX then 0 else if reducedX then nS - 1 else nS	Number of structurally independent mass fractions (see docu for details)
nC=size(extraPropertiesNames, 1)	Number of extra (outside of standard mass-balance) transported properties
C_nominal=1.0e-6*ones(nC)	Default for the nominal values for the extra properties
FluidConstants	Critical, triple, molecular and other standard data of fluid
prandtlNumber	Return the Prandtl number
heatCapacity_cp	Alias for deprecated name
heatCapacity_cv	Alias for deprecated name
beta	Alias for isobaricExpansionCoefficient for user convenience
kappa	Alias of isothermalCompressibility for user convenience
specificEnthalpy_pTX	Return specific enthalpy from p, T, and X or Xi
specificEntropy_pTX	Return specific enthalpy from p, T, and X or Xi
density_pTX	Return density from p, T, and X or Xi
temperature_phX	Return temperature from p, h, and X or Xi
density_phX	Return density from p, h, and X or Xi
temperature_psX	Return temperature from p,s, and X or Xi
density_psX	Return density from p, s, and X or Xi
specificEnthalpy_psX	Return specific enthalpy from p, s, and X or Xi
MassFlowRate	Type for mass flow rate with medium specific attributes
AbsolutePressure	Type for absolute pressure with medium specific attributes
Density	Type for density with medium specific attributes
DynamicViscosity	Type for dynamic viscosity with medium specific attributes
EnthalpyFlowRate	Type for enthalpy flow rate with medium specific attributes
MassFraction	Type for mass fraction with medium specific attributes
MoleFraction	Type for mole fraction with medium specific attributes
MolarMass	Type for molar mass with medium specific attributes
MolarVolume	Type for molar volume with medium specific attributes
IsentropicExponent	Type for isentropic exponent with medium specific attributes
SpecificEnergy	Type for specific energy with medium specific attributes
SpecificInternalEnergy	Type for specific internal energy with medium specific attributes
SpecificEnthalpy	Type for specific enthalpy with medium specific attributes
SpecificEntropy	Type for specific entropy with medium specific attributes
SpecificHeatCapacity	Type for specific heat capacity with medium specific attributes
SurfaceTension	Type for surface tension with medium specific attributes
Temperature	Type for temperature with medium specific attributes
ThermalConductivity	Type for thermal conductivity with medium specific attributes
PrandtlNumber	Type for Prandtl number with medium specific attributes
VelocityOfSound	Type for velocity of sound with medium specific attributes
ExtraProperty	Type for unspecified, mass-specific property transported by flow
CumulativeExtraProperty	Type for conserved integral of unspecified, mass specific property
ExtraPropertyFlowRate	Type for flow rate of unspecified, mass-specific property
IsobaricExpansionCoefficient	Type for isobaric expansion coefficient with medium specific attributes
DipoleMoment	Type for dipole moment with medium specific attributes
DerDensityByPressure	Type for partial derivative of density with respect to pressure with medium specific attributes
DerDensityByEnthalpy	Type for partial derivative of density with respect to enthalpy with medium specific attributes
DerEnthalpyByPressure	Type for partial derivative of enthalpy with respect to pressure with medium specific attributes
DerDensityByTemperature	Type for partial derivative of density with respect to temperature with medium specific attributes
DerTemperatureByPressure	Type for partial derivative of temperature with respect to pressure with medium specific attributes
SaturationProperties	Saturation properties of two phase medium
FluidLimits	Validity limits for fluid model
FixedPhase	Phase of the fluid: 1 for 1-phase, 2 for two-phase, 0 for not known, e.g., interactive use
Basic	The most basic version of a record used in several degrees of detail
IdealGas	The ideal gas version of a record used in several degrees of detail
TwoPhase	The two phase fluid version of a record used in several degrees of detail

Modelica.Media.Air.MoistAir.ThermodynamicState

ThermodynamicState record for moist air

Information

Extends from (Thermodynamic state variables).

Modelica.Media.Air.MoistAir.BaseProperties

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, pressure p 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.

Extends from (Base properties (p, d, T, h, u, R, MM and, if applicable, X and Xi) of a medium).

Parameters

Modelica.Media.Air.MoistAir.setState_pTX

Return thermodynamic state as function of pressure p, temperature T and composition X

Information

Extends from Modelica.Icons.Function (Icon for functions).

Inputs

Outputs

Modelica.Media.Air.MoistAir.setState_phX

Return thermodynamic state as function of pressure p, specific enthalpy h and composition X

Information

Extends from Modelica.Icons.Function (Icon for functions).

Inputs

Outputs

Modelica.Media.Air.MoistAir.setState_dTX

Return thermodynamic state as function of density d, temperature T and composition X

Information

Extends from Modelica.Icons.Function (Icon for functions).

Inputs

Outputs

Modelica.Media.Air.MoistAir.setSmoothState

Return thermodynamic state so that it smoothly approximates: if x > 0 then state_a else state_b

Information

Extends from (Return thermodynamic state so that it smoothly approximates: if x > 0 then state_a else state_b).

Inputs

Outputs

Modelica.Media.Air.MoistAir.Xsaturation

Return absolute humidity per unit mass of moist air at saturation as a function of the thermodynamic state record

Information

Extends from Modelica.Icons.Function (Icon for functions).

Inputs

Outputs

Modelica.Media.Air.MoistAir.xsaturation

Return absolute humidity per unit mass of dry air at saturation as a function of the thermodynamic state record

Information

Extends from Modelica.Icons.Function (Icon for functions).

Inputs

Outputs

Modelica.Media.Air.MoistAir.xsaturation_pT

Return absolute humidity per unit mass of dry air at saturation as a function of pressure p and temperature T

Information

Extends from Modelica.Icons.Function (Icon for functions).

Inputs

Outputs

Modelica.Media.Air.MoistAir.massFraction_pTphi

Return steam mass fraction as a function of relative humidity phi and temperature T

Information

Extends from Modelica.Icons.Function (Icon for functions).

Inputs

Outputs

Modelica.Media.Air.MoistAir.relativeHumidity_pTX

Return relative humidity as a function of pressure p, temperature T and composition X

Information

Extends from Modelica.Icons.Function (Icon for functions).

Inputs

Outputs

Modelica.Media.Air.MoistAir.relativeHumidity

Return relative humidity as a function of the thermodynamic state record

Information

Extends from Modelica.Icons.Function (Icon for functions).

Inputs

Outputs

Modelica.Media.Air.MoistAir.gasConstant

Return ideal gas constant as a function from thermodynamic state, only valid for phi<1

Information

Extends from (Return the gas constant of the mixture (also for liquids)).

Inputs

Outputs

Modelica.Media.Air.MoistAir.gasConstant_X

Return ideal gas constant as a function from composition X

Information

Extends from Modelica.Icons.Function (Icon for functions).

Inputs

Outputs

Modelica.Media.Air.MoistAir.saturationPressureLiquid

Return saturation pressure of water as a function of temperature T in the range of 273.16 to 647.096 K

Information

Saturation pressure of water above the triple point temperature is computed from temperature.

Source: A Saul, W Wagner: "International equations for the saturation properties of ordinary water substance", equation 2.1

Extends from Modelica.Icons.Function (Icon for functions).

Inputs

Outputs

Modelica.Media.Air.MoistAir.saturationPressureLiquid_der

Derivative function for 'saturationPressureLiquid'

Information

Saturation pressure of water above the triple point temperature is computed from temperature.

Source: A Saul, W Wagner: "International equations for the saturation properties of ordinary water substance", equation 2.1

Extends from Modelica.Icons.Function (Icon for functions).

Inputs

Outputs

Modelica.Media.Air.MoistAir.sublimationPressureIce

Return sublimation pressure of water as a function of temperature T between 190 and 273.16 K

Information

Sublimation pressure of water below the triple point temperature is computed from temperature.

Source: W Wagner, A Saul, A Pruss: "International equations for the pressure along the melting and along the sublimation curve of ordinary water substance", equation 3.5

Extends from Modelica.Icons.Function (Icon for functions).

Inputs

Outputs

Modelica.Media.Air.MoistAir.sublimationPressureIce_der

Derivative function for 'sublimationPressureIce'

Information

Sublimation pressure of water below the triple point temperature is computed from temperature.

Source: W Wagner, A Saul, A Pruss: "International equations for the pressure along the melting and along the sublimation curve of ordinary water substance", equation 3.5

Extends from Modelica.Icons.Function (Icon for functions).

Inputs

Outputs

Modelica.Media.Air.MoistAir.saturationPressure

Return saturation pressure of water as a function of temperature T between 190 and 647.096 K

Information

Extends from (Return saturation pressure of condensing fluid).

Inputs

Outputs

Modelica.Media.Air.MoistAir.saturationPressure_der

Derivative function for 'saturationPressure'

Information

Extends from Modelica.Icons.Function (Icon for functions).

Inputs

Outputs

Modelica.Media.Air.MoistAir.saturationTemperature

Return saturation temperature of water as a function of (partial) pressure p

Information

Extends from Modelica.Icons.Function (Icon for functions).

Inputs

Outputs

Modelica.Media.Air.MoistAir.enthalpyOfVaporization

Return enthalpy of vaporization of water as a function of temperature T, 273.16 to 647.096 K

Information

Enthalpy of vaporization of water is computed from temperature in the region of 273.16 to 647.096 K.

Source: W Wagner, A Pruss: "International equations for the saturation properties of ordinary water substance. Revised according to the international temperature scale of 1990" (1993).

Extends from (Return vaporization enthalpy of condensing fluid).

Inputs

Outputs

Modelica.Media.Air.MoistAir.HeatCapacityOfWater

Return specific heat capacity of water (liquid only) as a function of temperature T

Information

Extends from Modelica.Icons.Function (Icon for functions).

Inputs

Outputs

Modelica.Media.Air.MoistAir.enthalpyOfLiquid

Return enthalpy of liquid water as a function of temperature T(use enthalpyOfWater instead)

Information

Extends from (Return liquid enthalpy of condensing fluid).

Inputs

Outputs

Modelica.Media.Air.MoistAir.enthalpyOfGas

Return specific enthalpy of gas (air and steam) as a function of temperature T and composition X

Information

Extends from (Return enthalpy of non-condensing gas mixture).

Inputs

Outputs

Modelica.Media.Air.MoistAir.enthalpyOfCondensingGas

Return specific enthalpy of steam as a function of temperature T

Information

Extends from (Return enthalpy of condensing gas (most often steam)).

Inputs

Outputs

Modelica.Media.Air.MoistAir.enthalpyOfNonCondensingGas

Return specific enthalpy of dry air as a function of temperature T

Information

Extends from (Return enthalpy of the non-condensing species).

Inputs

Outputs

Modelica.Media.Air.MoistAir.enthalpyOfWater

Computes specific enthalpy of water (solid/liquid) near atmospheric pressure from temperature T

Information

• heat capacity of liquid water:4200 J/kg
• heat capacity of solid water: 2050 J/kg
• enthalpy of fusion (liquid=>solid): 333000 J/kg

Extends from Modelica.Icons.Function (Icon for functions).

Inputs

Outputs

Modelica.Media.Air.MoistAir.enthalpyOfWater_der

Derivative function of enthalpyOfWater

Information

Extends from Modelica.Icons.Function (Icon for functions).

Inputs

Outputs

Modelica.Media.Air.MoistAir.pressure

Returns pressure of ideal gas as a function of the thermodynamic state record

Information

Extends from (Return pressure).

Inputs

Outputs

Modelica.Media.Air.MoistAir.temperature

Return temperature of ideal gas as a function of the thermodynamic state record

Information

Extends from (Return temperature).

Inputs

Outputs

Modelica.Media.Air.MoistAir.T_phX

Return temperature as a function of pressure p, specific enthalpy h and composition X

Information

Extends from Modelica.Icons.Function (Icon for functions).

Inputs

Outputs

Modelica.Media.Air.MoistAir.density

Returns density of ideal gas as a function of the thermodynamic state record

Information

Extends from (Return density).

Inputs

Outputs

Modelica.Media.Air.MoistAir.specificEnthalpy

Return specific enthalpy of moist air as a function of the thermodynamic state record

Information

Extends from (Return specific enthalpy).

Inputs

Outputs

Modelica.Media.Air.MoistAir.h_pTX

Return specific enthalpy of moist air as a function of pressure p, temperature T and composition X

Information

Extends from Modelica.Icons.Function (Icon for functions).

Inputs

Outputs

Modelica.Media.Air.MoistAir.h_pTX_der

Derivative function of h_pTX

Information

Extends from Modelica.Icons.Function (Icon for functions).

Inputs

Outputs

Modelica.Media.Air.MoistAir.isentropicExponent

Return isentropic exponent (only for gas fraction!)

Information

Extends from (Return isentropic exponent).

Inputs

Outputs

Modelica.Media.Air.MoistAir.isentropicEnthalpyApproximation

Approximate calculation of h_is from upstream properties, downstream pressure, gas part only

Information

Extends from Modelica.Icons.Function (Icon for functions).

Inputs

Outputs

Modelica.Media.Air.MoistAir.specificInternalEnergy

Return specific internal energy of moist air as a function of the thermodynamic state record

Information

Extends from Modelica.Icons.Function (Icon for functions), (Return specific internal energy).

Inputs

Outputs

Modelica.Media.Air.MoistAir.specificInternalEnergy_pTX

Return specific internal energy of moist air as a function of pressure p, temperature T and composition X

Information

Extends from Modelica.Icons.Function (Icon for functions).

Inputs

Outputs

Modelica.Media.Air.MoistAir.specificInternalEnergy_pTX_der

Derivative function for specificInternalEnergy_pTX

Information

Extends from Modelica.Icons.Function (Icon for functions).

Inputs

Outputs

Modelica.Media.Air.MoistAir.specificEntropy

Return specific entropy from thermodynamic state record, only valid for phi<1

Information

Extends from (Return specific entropy).

Inputs

Outputs

Modelica.Media.Air.MoistAir.specificGibbsEnergy

Return specific Gibbs energy as a function of the thermodynamic state record, only valid for phi<1

Information

Extends from Modelica.Icons.Function (Icon for functions), (Return specific Gibbs energy).

Inputs

Outputs

Modelica.Media.Air.MoistAir.specificHelmholtzEnergy

Return specific Helmholtz energy as a function of the thermodynamic state record, only valid for phi<1

Information

Extends from Modelica.Icons.Function (Icon for functions), (Return specific Helmholtz energy).

Inputs

Outputs

Modelica.Media.Air.MoistAir.specificHeatCapacityCp

Return specific heat capacity at constant pressure as a function of the thermodynamic state record

Information

Extends from (Return specific heat capacity at constant pressure).

Inputs

Outputs

Modelica.Media.Air.MoistAir.specificHeatCapacityCv

Return specific heat capacity at constant volume as a function of the thermodynamic state record

Information

Extends from (Return specific heat capacity at constant volume).

Inputs

Outputs

Modelica.Media.Air.MoistAir.dynamicViscosity

Return dynamic viscosity as a function of the thermodynamic state record, valid from 123.15 K to 1273.15 K

Information

Dynamic viscosity is computed from temperature using a simple polynomial for dry air. Range of validity is from 123.15 K to 1273.15 K. The influence of pressure and moisture is neglected.

Source: VDI Waermeatlas, 8th edition.

Extends from (Return dynamic viscosity).

Inputs

Outputs

Modelica.Media.Air.MoistAir.thermalConductivity

Return thermal conductivity as a function of the thermodynamic state record, valid from 123.15 K to 1273.15 K

Information

Thermal conductivity is computed from temperature using a simple polynomial for dry air. Range of validity is from 123.15 K to 1273.15 K. The influence of pressure and moisture is neglected.

Source: VDI Waermeatlas, 8th edition.

Extends from (Return thermal conductivity).

Inputs

Outputs

Modelica.Media.Air.MoistAir.velocityOfSound

Information

Extends from (Return velocity of sound).

Inputs

Outputs

Modelica.Media.Air.MoistAir.isobaricExpansionCoefficient

Information

Extends from (Return overall the isobaric expansion coefficient beta).

Inputs

Outputs

Modelica.Media.Air.MoistAir.isothermalCompressibility

Information

Extends from (Return overall the isothermal compressibility factor).

Inputs

Outputs

Modelica.Media.Air.MoistAir.density_derp_h

Information

Extends from (Return density derivative w.r.t. pressure at const specific enthalpy).

Inputs

Outputs

Modelica.Media.Air.MoistAir.density_derh_p

Information

Extends from (Return density derivative w.r.t. specific enthalpy at constant pressure).

Inputs

Outputs

Modelica.Media.Air.MoistAir.density_derp_T

Information

Extends from (Return density derivative w.r.t. pressure at const temperature).

Inputs

Outputs

Modelica.Media.Air.MoistAir.density_derT_p

Information

Extends from (Return density derivative w.r.t. temperature at constant pressure).

Inputs

Outputs

Modelica.Media.Air.MoistAir.density_derX

Information

Extends from (Return density derivative w.r.t. mass fraction).

Inputs

Outputs

Modelica.Media.Air.MoistAir.molarMass

Information

Extends from (Return the molar mass of the medium).

Inputs

Outputs

Modelica.Media.Air.MoistAir.T_psX

Return temperature as a function of pressure p, specific entropy s and composition X

Information

Extends from Modelica.Icons.Function (Icon for functions).

Inputs

Outputs

Modelica.Media.Air.MoistAir.setState_psX

Information

Extends from (Return thermodynamic state as function of p, s and composition X or Xi).

Inputs

Outputs

Modelica.Media.Air.MoistAir.s_pTX

Return specific entropy of moist air as a function of pressure p, temperature T and composition X (only valid for phi<1)

Information

Extends from Modelica.Icons.Function (Icon for functions).

Inputs

Outputs

Modelica.Media.Air.MoistAir.s_pTX_der

Return specific entropy of moist air as a function of pressure p, temperature T and composition X (only valid for phi<1)

Information

Extends from Modelica.Icons.Function (Icon for functions).

Inputs

Outputs

Modelica.Media.Air.MoistAir.isentropicEnthalpy

Isentropic enthalpy (only valid for phi<1)

Information

Extends from Modelica.Icons.Function (Icon for functions), (Return isentropic enthalpy).

Inputs

Outputs