Package with moist air model with constant density
This is a medium model that is similar to Buildings.Obsolete.Media.PerfectGases.MoistAir, but the mass density is constant.
The use of a constant density avoids having pressure as a state variable in mixing volumes. Hence, fast transients introduced by a change in pressure are avoided. The drawback is that the dimensionality of the coupled nonlinear equation system is typically larger for flow networks.
As in
Buildings.Obsolete.Media.PerfectGases.MoistAir, the
specific enthalpy h and specific internal energy u are only
a function of temperature T
and
species concentration X
and all other provided medium
quantities are constant.
Extends from Modelica.Media.Interfaces.PartialCondensingGases (Base class for mixtures of condensing and non-condensing gases).
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=Buildings.Obsolete.Media.PerfectGases.Common.SingleGasData.Air | |
steam=Buildings.Obsolete.Media.PerfectGases.Common.SingleGasData.H2O | |
pStp=101325 | Pressure for which dStp is defined |
dStp=1.2 | Fluid density at pressure pStp |
ThermodynamicState | ThermodynamicState record for moist air |
BaseProperties | |
Xsaturation | Steam water mass fraction of saturation boundary in kg_water/kg_moistair |
setState_pTX | Thermodynamic state as function of p, T and composition X |
setState_phX | Thermodynamic state as function of p, h and composition X |
setState_dTX | Thermodynamic state as function of d, T and composition X |
gasConstant | Gas constant (computation neglects liquid fraction) |
saturationPressureLiquid | Saturation curve valid for 273.16 <= T <= 373.16. Outside of these limits a (less accurate) result is returned |
saturationPressureLiquid_der | Saturation curve valid for 273.16 <= T <= 373.16. Outside of these limits a (less accurate) result is returned |
sublimationPressureIce | Saturation curve valid for 223.16 <= T <= 273.16. Outside of these limits a (less accurate) result is returned |
saturationPressure | Saturation curve valid for 223.16 <= T <= 373.16 (and slightly outside with less accuracy) |
pressure | Gas pressure |
temperature | Gas temperature |
density | Gas density |
specificEntropy | Specific entropy (liquid part neglected, mixing entropy included) |
enthalpyOfVaporization | Enthalpy of vaporization of water |
HeatCapacityOfWater | Specific heat capacity of water (liquid only) which is constant |
enthalpyOfLiquid | Enthalpy of liquid (per unit mass of liquid) which is linear in the temperature |
der_enthalpyOfLiquid | Temperature derivative of enthalpy of liquid per unit mass of liquid |
enthalpyOfCondensingGas | Enthalpy of steam per unit mass of steam |
der_enthalpyOfCondensingGas | Derivative of enthalpy of steam per unit mass of steam |
enthalpyOfNonCondensingGas | Enthalpy of non-condensing gas per unit mass of steam |
der_enthalpyOfNonCondensingGas | Derivative of enthalpy of non-condensing gas per unit mass of steam |
enthalpyOfGas | Enthalpy of gas mixture per unit mass of gas mixture |
enthalpyOfDryAir | Enthalpy of dry air per unit mass of dry air |
der_enthalpyOfDryAir | Derivative of enthalpy of dry air per unit mass of dry air |
specificHeatCapacityCp | Specific heat capacity of gas mixture at constant pressure |
specificHeatCapacityCv | Specific heat capacity of gas mixture at constant volume |
dynamicViscosity | dynamic viscosity of dry air |
thermalConductivity | Thermal conductivity of dry air as a polynomial in the temperature |
h_pTX | Compute specific enthalpy from pressure, temperature and mass fraction |
specificEnthalpy | Specific enthalpy |
specificInternalEnergy | Specific internal energy |
specificGibbsEnergy | Specific Gibbs energy |
specificHelmholtzEnergy | Specific Helmholtz energy |
T_phX | Compute temperature from specific enthalpy and mass fraction |
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 |
setState_psX | Return thermodynamic state as function of p, s and composition X or Xi |
setSmoothState | Return thermodynamic state so that it smoothly approximates: if x > 0 then state_a else state_b |
prandtlNumber | Return the Prandtl number |
heatCapacity_cp | Alias for deprecated name |
heatCapacity_cv | Alias for deprecated name |
isentropicExponent | Return isentropic exponent |
isentropicEnthalpy | Return isentropic enthalpy |
velocityOfSound | Return velocity of sound |
isobaricExpansionCoefficient | Return overall the isobaric expansion coefficient beta |
beta | Alias for isobaricExpansionCoefficient for user convenience |
isothermalCompressibility | Return overall the isothermal compressibility factor |
kappa | Alias of isothermalCompressibility for user convenience |
density_derp_h | Return density derivative w.r.t. pressure at const specific enthalpy |
density_derh_p | Return density derivative w.r.t. specific enthalpy at constant pressure |
density_derp_T | Return density derivative w.r.t. pressure at const temperature |
density_derT_p | Return density derivative w.r.t. temperature at constant pressure |
density_derX | Return density derivative w.r.t. mass fraction |
molarMass | Return the molar mass of the medium |
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 |
constant Integer Water=1 "Index of water (in substanceNames, massFractions X, etc.)";
constant Integer Air=2 "Index of air (in substanceNames, massFractions X, etc.)";
constant Real k_mair = steam.MM/dryair.MM "ratio of molar weights";
constant Buildings.Obsolete.Media.PerfectGases.Common.DataRecord dryair=
Buildings.Obsolete.Media.PerfectGases.Common.SingleGasData.Air;
constant Buildings.Obsolete.Media.PerfectGases.Common.DataRecord steam=
Buildings.Obsolete.Media.PerfectGases.Common.SingleGasData.H2O;
constant AbsolutePressure pStp = 101325 "Pressure for which dStp is defined";
constant Density dStp = 1.2 "Fluid density at pressure pStp";
ThermodynamicState record for moist air
Extends from (Thermodynamic state variables).
Extends from (Base properties (p, d, T, h, u, R, MM and, if applicable, X and Xi) of a medium).
Type | Name | Default | Description |
---|---|---|---|
Boolean | standardOrderComponents | true | If true, and reducedX = true, the last element of X will be computed from the other ones |
Advanced | |||
Boolean | preferredMediumStates | false | = true if StateSelect.prefer shall be used for the independent property variables of the medium |
Steam water mass fraction of saturation boundary in kg_water/kg_moistair
Type | Name | Default | Description |
---|---|---|---|
ThermodynamicState | state | Thermodynamic state record |
Type | Name | Description |
---|---|---|
MassFraction | X_sat | Steam mass fraction of sat. boundary [kg/kg] |
Thermodynamic state as function of p, T and composition X
Extends from Buildings.Obsolete.Media.PerfectGases.MoistAir.setState_pTX (Thermodynamic state as function of p, T and composition X).
Type | Name | Default | Description |
---|---|---|---|
AbsolutePressure | p | Pressure [Pa] | |
Temperature | T | Temperature [K] | |
MassFraction | X[:] | reference_X | Mass fractions [kg/kg] |
Type | Name | Description |
---|---|---|
ThermodynamicState | state | Thermodynamic state |
Thermodynamic state as function of p, h and composition X
T_phX
provided by this package as opposed to the
implementation provided by its parent package.
Extends from Modelica.Icons.Function (Icon for functions).
Type | Name | Default | Description |
---|---|---|---|
AbsolutePressure | p | Pressure [Pa] | |
SpecificEnthalpy | h | Specific enthalpy [J/kg] | |
MassFraction | X[:] | Mass fractions [kg/kg] |
Type | Name | Description |
---|---|---|
ThermodynamicState | state |
Thermodynamic state as function of d, T and composition X
Extends from Modelica.Icons.Function (Icon for functions).
Type | Name | Default | Description |
---|---|---|---|
Density | d | density [kg/m3] | |
Temperature | T | Temperature [K] | |
MassFraction | X[:] | reference_X | Mass fractions [kg/kg] |
Type | Name | Description |
---|---|---|
ThermodynamicState | state | Thermodynamic state |
Gas constant (computation neglects liquid fraction)
Extends from Buildings.Obsolete.Media.PerfectGases.MoistAir.gasConstant (Gas constant (computation neglects liquid fraction)).
Type | Name | Default | Description |
---|---|---|---|
ThermodynamicState | state | Thermodynamic state |
Type | Name | Description |
---|---|---|
SpecificHeatCapacity | R | Mixture gas constant [J/(kg.K)] |
Saturation curve valid for 273.16 <= T <= 373.16. Outside of these limits a (less accurate) result is returned
Type | Name | Default | Description |
---|---|---|---|
Temperature | Tsat | saturation temperature [K] |
Type | Name | Description |
---|---|---|
AbsolutePressure | psat | saturation pressure [Pa] |
Saturation curve valid for 273.16 <= T <= 373.16. Outside of these limits a (less accurate) result is returned
saturationPressureLiquid
.
Extends from Buildings.Obsolete.Media.PerfectGases.MoistAir.saturationPressureLiquid_der (Time derivative of saturationPressureLiquid).
Type | Name | Default | Description |
---|---|---|---|
Temperature | Tsat | Saturation temperature [K] | |
Real | dTsat | Saturation temperature derivative [K/s] |
Type | Name | Description |
---|---|---|
Real | psat_der | Saturation pressure [Pa/s] |
Saturation curve valid for 223.16 <= T <= 273.16. Outside of these limits a (less accurate) result is returned
Type | Name | Default | Description |
---|---|---|---|
Temperature | Tsat | Sublimation temperature [K] |
Type | Name | Description |
---|---|---|
AbsolutePressure | psat | Sublimation pressure [Pa] |
Saturation curve valid for 223.16 <= T <= 373.16 (and slightly outside with less accuracy)
Extends from (Return saturation pressure of condensing fluid).
Type | Name | Default | Description |
---|---|---|---|
Temperature | Tsat | Saturation temperature [K] |
Type | Name | Description |
---|---|---|
AbsolutePressure | psat | Saturation pressure [Pa] |
Gas pressure
Extends from Buildings.Obsolete.Media.PerfectGases.MoistAir.pressure (Gas pressure).
Type | Name | Default | Description |
---|---|---|---|
ThermodynamicState | state | Thermodynamic state record |
Type | Name | Description |
---|---|---|
AbsolutePressure | p | Pressure [Pa] |
Gas temperature
Extends from Buildings.Obsolete.Media.PerfectGases.MoistAir.temperature (Gas temperature).
Type | Name | Default | Description |
---|---|---|---|
ThermodynamicState | state | Thermodynamic state record |
Type | Name | Description |
---|---|---|
Temperature | T | Temperature [K] |
Gas density
Extends from Modelica.Icons.Function (Icon for functions).
Type | Name | Default | Description |
---|---|---|---|
ThermodynamicState | state |
Type | Name | Description |
---|---|---|
Density | d | Density [kg/m3] |
Specific entropy (liquid part neglected, mixing entropy included)
Extends from Buildings.Obsolete.Media.PerfectGases.MoistAir.specificEntropy (Specific entropy (liquid part neglected, mixing entropy included)).
Type | Name | Default | Description |
---|---|---|---|
ThermodynamicState | state | Thermodynamic state record |
Type | Name | Description |
---|---|---|
SpecificEntropy | s | Specific entropy [J/(kg.K)] |
Enthalpy of vaporization of water
Extends from (Return vaporization enthalpy of condensing fluid).
Type | Name | Default | Description |
---|---|---|---|
Temperature | T | Temperature [K] |
Type | Name | Description |
---|---|---|
SpecificEnthalpy | r0 | Vaporization enthalpy [J/kg] |
Specific heat capacity of water (liquid only) which is constant
Extends from Modelica.Icons.Function (Icon for functions).
Type | Name | Default | Description |
---|---|---|---|
Temperature | T | [K] |
Type | Name | Description |
---|---|---|
SpecificHeatCapacity | cp_fl | [J/(kg.K)] |
Enthalpy of liquid (per unit mass of liquid) which is linear in the temperature
Extends from (Return liquid enthalpy of condensing fluid).
Type | Name | Default | Description |
---|---|---|---|
Temperature | T | Temperature [K] |
Type | Name | Description |
---|---|---|
SpecificEnthalpy | h | Liquid enthalpy [J/kg] |
Temperature derivative of enthalpy of liquid per unit mass of liquid
Extends from Modelica.Icons.Function (Icon for functions).
Type | Name | Default | Description |
---|---|---|---|
Temperature | T | temperature [K] | |
Real | der_T | temperature derivative |
Type | Name | Description |
---|---|---|
Real | der_h | derivative of liquid enthalpy |
Enthalpy of steam per unit mass of steam
Extends from Modelica.Icons.Function (Icon for functions).
Type | Name | Default | Description |
---|---|---|---|
Temperature | T | temperature [K] |
Type | Name | Description |
---|---|---|
SpecificEnthalpy | h | steam enthalpy [J/kg] |
Derivative of enthalpy of steam per unit mass of steam
Extends from Modelica.Icons.Function (Icon for functions).
Type | Name | Default | Description |
---|---|---|---|
Temperature | T | temperature [K] | |
Real | der_T | temperature derivative |
Type | Name | Description |
---|---|---|
Real | der_h | derivative of steam enthalpy |
Enthalpy of non-condensing gas per unit mass of steam
Extends from Modelica.Icons.Function (Icon for functions).
Type | Name | Default | Description |
---|---|---|---|
Temperature | T | temperature [K] |
Type | Name | Description |
---|---|---|
SpecificEnthalpy | h | enthalpy [J/kg] |
Derivative of enthalpy of non-condensing gas per unit mass of steam
Extends from Modelica.Icons.Function (Icon for functions).
Type | Name | Default | Description |
---|---|---|---|
Temperature | T | temperature [K] | |
Real | der_T | temperature derivative |
Type | Name | Description |
---|---|---|
Real | der_h | derivative of steam enthalpy |
Enthalpy of gas mixture per unit mass of gas mixture
Extends from (Return enthalpy of non-condensing gas mixture).
Type | Name | Default | Description |
---|---|---|---|
Temperature | T | Temperature [K] | |
MassFraction | X[:] | Vector of mass fractions [kg/kg] |
Type | Name | Description |
---|---|---|
SpecificEnthalpy | h | Specific enthalpy [J/kg] |
Enthalpy of dry air per unit mass of dry air
Extends from Modelica.Icons.Function (Icon for functions).
Type | Name | Default | Description |
---|---|---|---|
Temperature | T | temperature [K] |
Type | Name | Description |
---|---|---|
SpecificEnthalpy | h | dry air enthalpy [J/kg] |
Derivative of enthalpy of dry air per unit mass of dry air
Extends from Modelica.Icons.Function (Icon for functions).
Type | Name | Default | Description |
---|---|---|---|
Temperature | T | temperature [K] | |
Real | der_T | temperature derivative |
Type | Name | Description |
---|---|---|
Real | der_h | derivative of dry air enthalpy |
Specific heat capacity of gas mixture at constant pressure
Type | Name | Default | Description |
---|---|---|---|
ThermodynamicState | state | Thermodynamic state record |
Type | Name | Description |
---|---|---|
SpecificHeatCapacity | cp | Specific heat capacity at constant pressure [J/(kg.K)] |
Specific heat capacity of gas mixture at constant volume
Type | Name | Default | Description |
---|---|---|---|
ThermodynamicState | state | Thermodynamic state record |
Type | Name | Description |
---|---|---|
SpecificHeatCapacity | cv | Specific heat capacity at constant volume [J/(kg.K)] |
dynamic viscosity of dry air
Extends from (Return dynamic viscosity).
Type | Name | Default | Description |
---|---|---|---|
ThermodynamicState | state | Thermodynamic state record |
Type | Name | Description |
---|---|---|
DynamicViscosity | eta | Dynamic viscosity [Pa.s] |
Thermal conductivity of dry air as a polynomial in the temperature
Extends from (Return thermal conductivity).
Type | Name | Default | Description |
---|---|---|---|
ThermodynamicState | state | Thermodynamic state record |
Type | Name | Description |
---|---|---|
ThermalConductivity | lambda | Thermal conductivity [W/(m.K)] |
Compute specific enthalpy from pressure, temperature and mass fraction
Extends from Buildings.Obsolete.Media.PerfectGases.MoistAir.h_pTX (Compute specific enthalpy from pressure, temperature and mass fraction).
Type | Name | Default | Description |
---|---|---|---|
Pressure | p | Pressure [Pa] | |
Temperature | T | Temperature [K] | |
MassFraction | X[:] | Mass fractions of moist air [1] |
Type | Name | Description |
---|---|---|
SpecificEnthalpy | h | Specific enthalpy at p, T, X [J/kg] |
Specific enthalpy
Extends from (Return specific enthalpy).
Type | Name | Default | Description |
---|---|---|---|
ThermodynamicState | state | Thermodynamic state record |
Type | Name | Description |
---|---|---|
SpecificEnthalpy | h | Specific enthalpy [J/kg] |
Specific internal energy
Extends from Modelica.Icons.Function (Icon for functions), (Return specific internal energy).
Type | Name | Default | Description |
---|---|---|---|
ThermodynamicState | state | Thermodynamic state record |
Type | Name | Description |
---|---|---|
SpecificEnergy | u | Specific internal energy [J/kg] |
Specific Gibbs energy
Extends from Modelica.Icons.Function (Icon for functions), (Return specific Gibbs energy).
Type | Name | Default | Description |
---|---|---|---|
ThermodynamicState | state | Thermodynamic state record |
Type | Name | Description |
---|---|---|
SpecificEnergy | g | Specific Gibbs energy [J/kg] |
Specific Helmholtz energy
Extends from Modelica.Icons.Function (Icon for functions), (Return specific Helmholtz energy).
Type | Name | Default | Description |
---|---|---|---|
ThermodynamicState | state | Thermodynamic state record |
Type | Name | Description |
---|---|---|
SpecificEnergy | f | Specific Helmholtz energy [J/kg] |
Compute temperature from specific enthalpy and mass fraction
Extends from Buildings.Obsolete.Media.PerfectGases.MoistAir.T_phX (Compute temperature from specific enthalpy and mass fraction).
Type | Name | Default | Description |
---|---|---|---|
AbsolutePressure | p | Pressure [Pa] | |
SpecificEnthalpy | h | Specific enthalpy [J/kg] | |
MassFraction | X[:] | Mass fractions of composition [kg/kg] |
Type | Name | Description |
---|---|---|
Temperature | T | Temperature [K] |