Modelica.Media.IdealGases.Common.MixtureGasNasa

Medium model of a mixture of ideal gases based on NASA source

Information

This model calculates the medium properties for single component ideal gases.

Sources for model and literature:
Original Data: Computer program for calculation of complex chemical equilibrium compositions and applications. Part 1: Analysis Document ID: 19950013764 N (95N20180) File Series: NASA Technical Reports Report Number: NASA-RP-1311 E-8017 NAS 1.61:1311 Authors: Gordon, Sanford (NASA Lewis Research Center) Mcbride, Bonnie J. (NASA Lewis Research Center) Published: Oct 01, 1994.

Known limits of validity:
The data is valid for temperatures between 200 K and 6000 K. A few of the data sets for monatomic gases have a discontinuous 1st derivative at 1000 K, but this never caused problems so far.

This model has been copied from the ThermoFluid library. It has been developed by Hubertus Tummescheit.

Extends from Modelica.Media.Interfaces.PartialMixtureMedium (Base class for pure substances of several chemical substances).

Package Content

Name Description
Modelica.Media.IdealGases.Common.MixtureGasNasa.ThermodynamicState ThermodynamicState Thermodynamic state variables
data Data records of ideal gas substances
excludeEnthalpyOfFormation=true If true, enthalpy of formation Hf is not included in specific enthalpy h
referenceChoice=ReferenceEnthalpy.ZeroAt0K Choice of reference enthalpy
h_offset=0.0 User defined offset for reference enthalpy, if referenceChoice = UserDefined
MMX=data[:].MM Molar masses of components
methodForThermalConductivity=1  
Modelica.Media.IdealGases.Common.MixtureGasNasa.BaseProperties BaseProperties Base properties (p, d, T, h, u, R_s, MM, X, and Xi of NASA mixture gas
Modelica.Media.IdealGases.Common.MixtureGasNasa.setState_pTX setState_pTX Return thermodynamic state as function of p, T and composition X
Modelica.Media.IdealGases.Common.MixtureGasNasa.setState_phX setState_phX Return thermodynamic state as function of p, h and composition X
Modelica.Media.IdealGases.Common.MixtureGasNasa.setState_psX setState_psX Return thermodynamic state as function of p, s and composition X
Modelica.Media.IdealGases.Common.MixtureGasNasa.setState_dTX setState_dTX Return thermodynamic state as function of d, T and composition X
Modelica.Media.IdealGases.Common.MixtureGasNasa.setSmoothState setSmoothState Return thermodynamic state so that it smoothly approximates: if x > 0 then state_a else state_b
Modelica.Media.IdealGases.Common.MixtureGasNasa.pressure pressure Return pressure of ideal gas
Modelica.Media.IdealGases.Common.MixtureGasNasa.temperature temperature Return temperature of ideal gas
Modelica.Media.IdealGases.Common.MixtureGasNasa.density density Return density of ideal gas
Modelica.Media.IdealGases.Common.MixtureGasNasa.specificEnthalpy specificEnthalpy Return specific enthalpy
Modelica.Media.IdealGases.Common.MixtureGasNasa.specificInternalEnergy specificInternalEnergy Return specific internal energy
Modelica.Media.IdealGases.Common.MixtureGasNasa.specificEntropy specificEntropy Return specific entropy
Modelica.Media.IdealGases.Common.MixtureGasNasa.specificGibbsEnergy specificGibbsEnergy Return specific Gibbs energy
Modelica.Media.IdealGases.Common.MixtureGasNasa.specificHelmholtzEnergy specificHelmholtzEnergy Return specific Helmholtz energy
Modelica.Media.IdealGases.Common.MixtureGasNasa.h_TX h_TX Return specific enthalpy
Modelica.Media.IdealGases.Common.MixtureGasNasa.h_TX_der h_TX_der Return specific enthalpy derivative
Modelica.Media.IdealGases.Common.MixtureGasNasa.gasConstant gasConstant Return gasConstant
Modelica.Media.IdealGases.Common.MixtureGasNasa.specificHeatCapacityCp specificHeatCapacityCp Return specific heat capacity at constant pressure
Modelica.Media.IdealGases.Common.MixtureGasNasa.specificHeatCapacityCv specificHeatCapacityCv Return specific heat capacity at constant volume from temperature and gas data
Modelica.Media.IdealGases.Common.MixtureGasNasa.MixEntropy MixEntropy Return mixing entropy of ideal gases / R
Modelica.Media.IdealGases.Common.MixtureGasNasa.s_TX s_TX Return temperature dependent part of the entropy, expects full entropy vector
Modelica.Media.IdealGases.Common.MixtureGasNasa.isentropicExponent isentropicExponent Return isentropic exponent
Modelica.Media.IdealGases.Common.MixtureGasNasa.velocityOfSound velocityOfSound Return velocity of sound
Modelica.Media.IdealGases.Common.MixtureGasNasa.isentropicEnthalpyApproximation isentropicEnthalpyApproximation Approximate method of calculating h_is from upstream properties and downstream pressure
Modelica.Media.IdealGases.Common.MixtureGasNasa.isentropicEnthalpy isentropicEnthalpy Return isentropic enthalpy
Modelica.Media.IdealGases.Common.MixtureGasNasa.gasMixtureViscosity gasMixtureViscosity Return viscosities of gas mixtures at low pressures (Wilke method)
Modelica.Media.IdealGases.Common.MixtureGasNasa.dynamicViscosity dynamicViscosity Return mixture dynamic viscosity
Modelica.Media.IdealGases.Common.MixtureGasNasa.mixtureViscosityChung mixtureViscosityChung Return the viscosity of gas mixtures without access to component viscosities (Chung, et. al. rules)
Modelica.Media.IdealGases.Common.MixtureGasNasa.lowPressureThermalConductivity lowPressureThermalConductivity Return thermal conductivities of low-pressure gas mixtures (Mason and Saxena Modification)
Modelica.Media.IdealGases.Common.MixtureGasNasa.thermalConductivity thermalConductivity Return thermal conductivity for low pressure gas mixtures
Modelica.Media.IdealGases.Common.MixtureGasNasa.isobaricExpansionCoefficient isobaricExpansionCoefficient Return isobaric expansion coefficient beta
Modelica.Media.IdealGases.Common.MixtureGasNasa.isothermalCompressibility isothermalCompressibility Return isothermal compressibility factor
Modelica.Media.IdealGases.Common.MixtureGasNasa.density_derp_T density_derp_T Return density derivative by pressure at constant temperature
Modelica.Media.IdealGases.Common.MixtureGasNasa.density_derT_p density_derT_p Return density derivative by temperature at constant pressure
Modelica.Media.IdealGases.Common.MixtureGasNasa.density_derX density_derX Return density derivative by mass fraction
Modelica.Media.IdealGases.Common.MixtureGasNasa.molarMass molarMass Return molar mass of mixture
Modelica.Media.IdealGases.Common.MixtureGasNasa.T_hX T_hX Return temperature from specific enthalpy and mass fraction
Modelica.Media.IdealGases.Common.MixtureGasNasa.T_psX T_psX Return temperature from pressure, specific entropy and mass fraction
Modelica.Media.IdealGases.Common.MixtureGasNasa.specificEntropyOfpTX specificEntropyOfpTX Return specific entropy from pressure, temperature and mass fractions
Inherited
fluidConstants Constant data for the fluid
Modelica.Media.Interfaces.PartialMixtureMedium.moleToMassFractions moleToMassFractions Return mass fractions X from mole fractions
Modelica.Media.Interfaces.PartialMixtureMedium.massToMoleFractions massToMoleFractions Return mole fractions from mass fractions X
ThermoStates=Modelica.Media.Interfaces.Choices.IndependentVariables.pTX Enumeration type for independent variables
mediumName="unusablePartialMedium" Name of the medium
substanceNames=data[:].name 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=false = true, if u and d are not a function of pressure
reducedX=false = 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.Units.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)
C_default=fill(0, nC) Default value for trace substances 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
Modelica.Media.Interfaces.PartialMedium.FluidConstants FluidConstants Critical, triple, molecular and other standard data of fluid
Modelica.Media.Interfaces.PartialMedium.prandtlNumber prandtlNumber Return the Prandtl number
Modelica.Media.Interfaces.PartialMedium.heatCapacity_cp heatCapacity_cp Alias for deprecated name
Modelica.Media.Interfaces.PartialMedium.heatCapacity_cv heatCapacity_cv Alias for deprecated name
Modelica.Media.Interfaces.PartialMedium.beta beta Alias for isobaricExpansionCoefficient for user convenience
Modelica.Media.Interfaces.PartialMedium.kappa kappa Alias of isothermalCompressibility for user convenience
Modelica.Media.Interfaces.PartialMedium.density_derp_h density_derp_h Return density derivative w.r.t. pressure at const specific enthalpy
Modelica.Media.Interfaces.PartialMedium.density_derh_p density_derh_p Return density derivative w.r.t. specific enthalpy at constant pressure
Modelica.Media.Interfaces.PartialMedium.specificEnthalpy_pTX specificEnthalpy_pTX Return specific enthalpy from p, T, and X or Xi
Modelica.Media.Interfaces.PartialMedium.specificEntropy_pTX specificEntropy_pTX Return specific enthalpy from p, T, and X or Xi
Modelica.Media.Interfaces.PartialMedium.density_pTX density_pTX Return density from p, T, and X or Xi
Modelica.Media.Interfaces.PartialMedium.temperature_phX temperature_phX Return temperature from p, h, and X or Xi
Modelica.Media.Interfaces.PartialMedium.density_phX density_phX Return density from p, h, and X or Xi
Modelica.Media.Interfaces.PartialMedium.temperature_psX temperature_psX Return temperature from p,s, and X or Xi
Modelica.Media.Interfaces.PartialMedium.density_psX density_psX Return density from p, s, and X or Xi
Modelica.Media.Interfaces.PartialMedium.specificEnthalpy_psX specificEnthalpy_psX Return specific enthalpy from p, s, and X or Xi
Modelica.Media.Interfaces.PartialMedium.MassFlowRate MassFlowRate Type for mass flow rate with medium specific attributes
Modelica.Media.Interfaces.Types.AbsolutePressure AbsolutePressure Type for absolute pressure with medium specific attributes
Modelica.Media.Interfaces.Types.Density Density Type for density with medium specific attributes
Modelica.Media.Interfaces.Types.DynamicViscosity DynamicViscosity Type for dynamic viscosity with medium specific attributes
Modelica.Media.Interfaces.Types.EnthalpyFlowRate EnthalpyFlowRate Type for enthalpy flow rate with medium specific attributes
Modelica.Media.Interfaces.Types.MassFraction MassFraction Type for mass fraction with medium specific attributes
Modelica.Media.Interfaces.Types.MoleFraction MoleFraction Type for mole fraction with medium specific attributes
Modelica.Media.Interfaces.Types.MolarMass MolarMass Type for molar mass with medium specific attributes
Modelica.Media.Interfaces.Types.MolarVolume MolarVolume Type for molar volume with medium specific attributes
Modelica.Media.Interfaces.Types.IsentropicExponent IsentropicExponent Type for isentropic exponent with medium specific attributes
Modelica.Media.Interfaces.Types.SpecificEnergy SpecificEnergy Type for specific energy with medium specific attributes
Modelica.Media.Interfaces.Types.SpecificInternalEnergy SpecificInternalEnergy Type for specific internal energy with medium specific attributes
Modelica.Media.Interfaces.Types.SpecificEnthalpy SpecificEnthalpy Type for specific enthalpy with medium specific attributes
Modelica.Media.Interfaces.Types.SpecificEntropy SpecificEntropy Type for specific entropy with medium specific attributes
Modelica.Media.Interfaces.Types.SpecificHeatCapacity SpecificHeatCapacity Type for specific heat capacity with medium specific attributes
Modelica.Media.Interfaces.Types.SurfaceTension SurfaceTension Type for surface tension with medium specific attributes
Modelica.Media.Interfaces.Types.Temperature Temperature Type for temperature with medium specific attributes
Modelica.Media.Interfaces.Types.ThermalConductivity ThermalConductivity Type for thermal conductivity with medium specific attributes
Modelica.Media.Interfaces.Types.PrandtlNumber PrandtlNumber Type for Prandtl number with medium specific attributes
Modelica.Media.Interfaces.Types.VelocityOfSound VelocityOfSound Type for velocity of sound with medium specific attributes
Modelica.Media.Interfaces.Types.ExtraProperty ExtraProperty Type for unspecified, mass-specific property transported by flow
Modelica.Media.Interfaces.Types.CumulativeExtraProperty CumulativeExtraProperty Type for conserved integral of unspecified, mass specific property
Modelica.Media.Interfaces.Types.ExtraPropertyFlowRate ExtraPropertyFlowRate Type for flow rate of unspecified, mass-specific property
Modelica.Media.Interfaces.Types.IsobaricExpansionCoefficient IsobaricExpansionCoefficient Type for isobaric expansion coefficient with medium specific attributes
Modelica.Media.Interfaces.Types.DipoleMoment DipoleMoment Type for dipole moment with medium specific attributes
Modelica.Media.Interfaces.Types.DerDensityByPressure DerDensityByPressure Type for partial derivative of density with respect to pressure with medium specific attributes
Modelica.Media.Interfaces.Types.DerDensityByEnthalpy DerDensityByEnthalpy Type for partial derivative of density with respect to enthalpy with medium specific attributes
Modelica.Media.Interfaces.Types.DerEnthalpyByPressure DerEnthalpyByPressure Type for partial derivative of enthalpy with respect to pressure with medium specific attributes
Modelica.Media.Interfaces.Types.DerDensityByTemperature DerDensityByTemperature Type for partial derivative of density with respect to temperature with medium specific attributes
Modelica.Media.Interfaces.Types.DerTemperatureByPressure DerTemperatureByPressure Type for partial derivative of temperature with respect to pressure with medium specific attributes
Modelica.Media.Interfaces.Types.SaturationProperties SaturationProperties Saturation properties of two phase medium
Modelica.Media.Interfaces.Types.FluidLimits FluidLimits Validity limits for fluid model
Modelica.Media.Interfaces.Types.FixedPhase FixedPhase Phase of the fluid: 1 for 1-phase, 2 for two-phase, 0 for not known, e.g., interactive use
Modelica.Media.Interfaces.Types.Basic Basic The most basic version of a record used in several degrees of detail
Modelica.Media.Interfaces.Types.IdealGas IdealGas The ideal gas version of a record used in several degrees of detail
Modelica.Media.Interfaces.Types.TwoPhase TwoPhase The two phase fluid version of a record used in several degrees of detail

Modelica.Media.IdealGases.Common.MixtureGasNasa.ThermodynamicState Modelica.Media.IdealGases.Common.MixtureGasNasa.ThermodynamicState

Thermodynamic state variables

Information

Extends from (Thermodynamic state variables).

Modelica.Media.IdealGases.Common.MixtureGasNasa.BaseProperties Modelica.Media.IdealGases.Common.MixtureGasNasa.BaseProperties

Base properties (p, d, T, h, u, R_s, MM, X, and Xi of NASA mixture gas

Information

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

Parameters

NameDescription
standardOrderComponentsIf true, and reducedX = true, the last element of X will be computed from the other ones
Advanced
preferredMediumStates= true if StateSelect.prefer shall be used for the independent property variables of the medium

Modelica.Media.IdealGases.Common.MixtureGasNasa.setState_pTX Modelica.Media.IdealGases.Common.MixtureGasNasa.setState_pTX

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

Information

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

Inputs

NameDescription
pPressure [Pa]
TTemperature [K]
X[:]Mass fractions [kg/kg]

Outputs

NameDescription
state 

Modelica.Media.IdealGases.Common.MixtureGasNasa.setState_phX Modelica.Media.IdealGases.Common.MixtureGasNasa.setState_phX

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

Information

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

Inputs

NameDescription
pPressure [Pa]
hSpecific enthalpy [J/kg]
X[:]Mass fractions [kg/kg]

Outputs

NameDescription
state 

Modelica.Media.IdealGases.Common.MixtureGasNasa.setState_psX Modelica.Media.IdealGases.Common.MixtureGasNasa.setState_psX

Return thermodynamic state as function of p, s and composition X

Information

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

Inputs

NameDescription
pPressure [Pa]
sSpecific entropy [J/(kg.K)]
X[:]Mass fractions [kg/kg]

Outputs

NameDescription
state 

Modelica.Media.IdealGases.Common.MixtureGasNasa.setState_dTX Modelica.Media.IdealGases.Common.MixtureGasNasa.setState_dTX

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

Information

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

Inputs

NameDescription
dDensity [kg/m3]
TTemperature [K]
X[:]Mass fractions [kg/kg]

Outputs

NameDescription
state 

Modelica.Media.IdealGases.Common.MixtureGasNasa.setSmoothState Modelica.Media.IdealGases.Common.MixtureGasNasa.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

NameDescription
xm_flow or dp
state_aThermodynamic state if x > 0
state_bThermodynamic state if x < 0
x_smallSmooth transition in the region -x_small < x < x_small

Outputs

NameDescription
stateSmooth thermodynamic state for all x (continuous and differentiable)

Modelica.Media.IdealGases.Common.MixtureGasNasa.pressure Modelica.Media.IdealGases.Common.MixtureGasNasa.pressure

Return pressure of ideal gas

Information

Extends from (Return pressure).

Inputs

NameDescription
stateThermodynamic state record

Outputs

NameDescription
pPressure [Pa]

Modelica.Media.IdealGases.Common.MixtureGasNasa.temperature Modelica.Media.IdealGases.Common.MixtureGasNasa.temperature

Return temperature of ideal gas

Information

Extends from (Return temperature).

Inputs

NameDescription
stateThermodynamic state record

Outputs

NameDescription
TTemperature [K]

Modelica.Media.IdealGases.Common.MixtureGasNasa.density Modelica.Media.IdealGases.Common.MixtureGasNasa.density

Return density of ideal gas

Information

Extends from (Return density).

Inputs

NameDescription
stateThermodynamic state record

Outputs

NameDescription
dDensity [kg/m3]

Modelica.Media.IdealGases.Common.MixtureGasNasa.specificEnthalpy Modelica.Media.IdealGases.Common.MixtureGasNasa.specificEnthalpy

Return specific enthalpy

Information

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

Inputs

NameDescription
stateThermodynamic state record

Outputs

NameDescription
hSpecific enthalpy [J/kg]

Modelica.Media.IdealGases.Common.MixtureGasNasa.specificInternalEnergy Modelica.Media.IdealGases.Common.MixtureGasNasa.specificInternalEnergy

Return specific internal energy

Information

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

Inputs

NameDescription
stateThermodynamic state record

Outputs

NameDescription
uSpecific internal energy [J/kg]

Modelica.Media.IdealGases.Common.MixtureGasNasa.specificEntropy Modelica.Media.IdealGases.Common.MixtureGasNasa.specificEntropy

Return specific entropy

Information

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

Inputs

NameDescription
stateThermodynamic state record

Outputs

NameDescription
sSpecific entropy [J/(kg.K)]

Modelica.Media.IdealGases.Common.MixtureGasNasa.specificGibbsEnergy Modelica.Media.IdealGases.Common.MixtureGasNasa.specificGibbsEnergy

Return specific Gibbs energy

Information

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

Inputs

NameDescription
stateThermodynamic state record

Outputs

NameDescription
gSpecific Gibbs energy [J/kg]

Modelica.Media.IdealGases.Common.MixtureGasNasa.specificHelmholtzEnergy Modelica.Media.IdealGases.Common.MixtureGasNasa.specificHelmholtzEnergy

Return specific Helmholtz energy

Information

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

Inputs

NameDescription
stateThermodynamic state record

Outputs

NameDescription
fSpecific Helmholtz energy [J/kg]

Modelica.Media.IdealGases.Common.MixtureGasNasa.h_TX Modelica.Media.IdealGases.Common.MixtureGasNasa.h_TX

Return specific enthalpy

Information

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

Inputs

NameDescription
TTemperature [K]
X[nX]Independent Mass fractions of gas mixture [kg/kg]
exclEnthFormIf true, enthalpy of formation Hf is not included in specific enthalpy h
refChoiceChoice of reference enthalpy
h_offUser defined offset for reference enthalpy, if referenceChoice = UserDefined [J/kg]

Outputs

NameDescription
hSpecific enthalpy at temperature T [J/kg]

Modelica.Media.IdealGases.Common.MixtureGasNasa.h_TX_der Modelica.Media.IdealGases.Common.MixtureGasNasa.h_TX_der

Return specific enthalpy derivative

Information

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

Inputs

NameDescription
TTemperature [K]
X[nX]Independent Mass fractions of gas mixture [kg/kg]
exclEnthFormIf true, enthalpy of formation Hf is not included in specific enthalpy h
refChoiceChoice of reference enthalpy
h_offUser defined offset for reference enthalpy, if referenceChoice = UserDefined [J/kg]
dTTemperature derivative
dX[nX]Independent mass fraction derivative

Outputs

NameDescription
h_derSpecific enthalpy at temperature T

Modelica.Media.IdealGases.Common.MixtureGasNasa.gasConstant Modelica.Media.IdealGases.Common.MixtureGasNasa.gasConstant

Return gasConstant

Information

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

Inputs

NameDescription
stateThermodynamic state

Outputs

NameDescription
R_sMixture gas constant [J/(kg.K)]

Modelica.Media.IdealGases.Common.MixtureGasNasa.specificHeatCapacityCp Modelica.Media.IdealGases.Common.MixtureGasNasa.specificHeatCapacityCp

Return specific heat capacity at constant pressure

Information

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

Inputs

NameDescription
stateThermodynamic state record

Outputs

NameDescription
cpSpecific heat capacity at constant pressure [J/(kg.K)]

Modelica.Media.IdealGases.Common.MixtureGasNasa.specificHeatCapacityCv Modelica.Media.IdealGases.Common.MixtureGasNasa.specificHeatCapacityCv

Return specific heat capacity at constant volume from temperature and gas data

Information

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

Inputs

NameDescription
stateThermodynamic state record

Outputs

NameDescription
cvSpecific heat capacity at constant volume [J/(kg.K)]

Modelica.Media.IdealGases.Common.MixtureGasNasa.MixEntropy Modelica.Media.IdealGases.Common.MixtureGasNasa.MixEntropy

Return mixing entropy of ideal gases / R

Information

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

Inputs

NameDescription
x[:]Mole fraction of mixture [1]

Outputs

NameDescription
smixMixing entropy contribution, divided by gas constant

Modelica.Media.IdealGases.Common.MixtureGasNasa.s_TX Modelica.Media.IdealGases.Common.MixtureGasNasa.s_TX

Return temperature dependent part of the entropy, expects full entropy vector

Information

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

Inputs

NameDescription
TTemperature [K]
X[nX]Mass fraction [kg/kg]

Outputs

NameDescription
sSpecific entropy [J/(kg.K)]

Modelica.Media.IdealGases.Common.MixtureGasNasa.isentropicExponent Modelica.Media.IdealGases.Common.MixtureGasNasa.isentropicExponent

Return isentropic exponent

Information

Extends from (Return isentropic exponent).

Inputs

NameDescription
stateThermodynamic state record

Outputs

NameDescription
gammaIsentropic exponent [1]

Modelica.Media.IdealGases.Common.MixtureGasNasa.velocityOfSound Modelica.Media.IdealGases.Common.MixtureGasNasa.velocityOfSound

Return velocity of sound

Information

Extends from Modelica.Icons.Function (Icon for functions), (Return velocity of sound).

Inputs

NameDescription
stateThermodynamic state record

Outputs

NameDescription
aVelocity of sound [m/s]

Modelica.Media.IdealGases.Common.MixtureGasNasa.isentropicEnthalpyApproximation Modelica.Media.IdealGases.Common.MixtureGasNasa.isentropicEnthalpyApproximation

Approximate method of calculating h_is from upstream properties and downstream pressure

Information

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

Inputs

NameDescription
p2Downstream pressure [Pa]
stateThermodynamic state at upstream location

Outputs

NameDescription
h_isIsentropic enthalpy [J/kg]

Modelica.Media.IdealGases.Common.MixtureGasNasa.isentropicEnthalpy Modelica.Media.IdealGases.Common.MixtureGasNasa.isentropicEnthalpy

Return isentropic enthalpy

Information

Extends from (Return isentropic enthalpy).

Inputs

NameDescription
p_downstreamDownstream pressure [Pa]
refStateReference state for entropy
exactFlag whether exact or approximate version should be used

Outputs

NameDescription
h_isIsentropic enthalpy [J/kg]

Modelica.Media.IdealGases.Common.MixtureGasNasa.gasMixtureViscosity Modelica.Media.IdealGases.Common.MixtureGasNasa.gasMixtureViscosity

Return viscosities of gas mixtures at low pressures (Wilke method)

Information

Simplification of the kinetic theory (Chapman and Enskog theory) approach neglecting the second-order effects.

This equation has been extensively tested (Amdur and Mason, 1958; Bromley and Wilke, 1951; Cheung, 1958; Dahler, 1959; Gandhi and Saxena, 1964; Ranz and Brodowsky, 1962; Saxena and Gambhir, 1963a; Strunk, et al., 1964; Vanderslice, et al. 1962; Wright and Gray, 1962). In most cases, only nonpolar mixtures were compared, and very good results obtained. For some systems containing hydrogen as one component, less satisfactory agreement was noted. Wilke's method predicted mixture viscosities that were larger than experimental for the H2-N2 system, but for H2-NH3, it underestimated the viscosities.
Gururaja, et al. (1967) found that this method also overpredicted in the H2-O2 case but was quite accurate for the H2-CO2 system.
Wilke's approximation has proved reliable even for polar-polar gas mixtures of aliphatic alcohols (Reid and Belenyessy, 1960). The principal reservation appears to lie in those cases where Mi>>Mj and etai>>etaj.

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

Inputs

NameDescription
yi[:]Mole fractions [mol/mol]
M[size(yi, 1)]Mole masses [kg/mol]
eta[size(yi, 1)]Pure component viscosities [Pa.s]

Outputs

NameDescription
etamViscosity of the mixture [Pa.s]

Modelica.Media.IdealGases.Common.MixtureGasNasa.dynamicViscosity Modelica.Media.IdealGases.Common.MixtureGasNasa.dynamicViscosity

Return mixture dynamic viscosity

Information

Extends from (Return dynamic viscosity).

Inputs

NameDescription
stateThermodynamic state record

Outputs

NameDescription
etaDynamic viscosity [Pa.s]

Modelica.Media.IdealGases.Common.MixtureGasNasa.mixtureViscosityChung Modelica.Media.IdealGases.Common.MixtureGasNasa.mixtureViscosityChung

Return the viscosity of gas mixtures without access to component viscosities (Chung, et. al. rules)

Information

Equation to estimate the viscosity of gas mixtures at low pressures.
It is a simplification of an extension of the rigorous kinetic theory of Chapman and Enskog to determine the viscosity of multicomponent mixtures, at low pressures and with a factor to correct for molecule shape and polarity.

The input argument Kappa is a special correction for highly polar substances such as alcohols and acids.
Values of kappa for a few such materials:

Compound
Kappa
Compound
Kappa
Methanol
0.215
n-Pentanol
0.122
Ethanol
0.175
n-Hexanol
0.114
n-Propanol
0.143
n-Heptanol
0.109
i-Propanol
0.143
Acetic Acid
0.0916
n-Butanol
0.132
Water
0.076
i-Butanol
0.132

Chung, et al. (1984) suggest that for other alcohols not shown in the table:
    
    kappa = 0.0682 + 4.704*[(number of -OH groups)]/[molecular weight]

S.I. units relation for the debyes: 
                                                       1 debye = 3.162e-25 (J.m^3)^(1/2)

References

[1] THE PROPERTIES OF GASES AND LIQUIDS, Fifth Edition,
          Bruce E. Poling, John M. Prausnitz, John P. O'Connell.
[2] Chung, T.-H., M. Ajlan, L. L. Lee, and K. E. Starling: Ind. Eng. Chem. Res., 27: 671 (1988).
[3] Chung, T.-H., L. L. Lee, and K. E. Starling; Ing. Eng. Chem. Fundam., 23: 3 ()1984).

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

Inputs

NameDescription
TTemperature [K]
Tc[nX]Critical temperatures [K]
Vcrit[nX]Critical volumes (m3/mol) [m3/mol]
w[nX]Acentric factors
mu[nX]Dipole moments (debyes)
MolecularWeights[nX]Molecular weights (kg/mol) [kg/mol]
y[nX]Molar Fractions [mol/mol]
kappa[nX]Association Factors

Outputs

NameDescription
etaMixtureMixture viscosity (Pa.s) [Pa.s]

Modelica.Media.IdealGases.Common.MixtureGasNasa.lowPressureThermalConductivity Modelica.Media.IdealGases.Common.MixtureGasNasa.lowPressureThermalConductivity

Return thermal conductivities of low-pressure gas mixtures (Mason and Saxena Modification)

Information

This function applies the Masson and Saxena modification of the Wassiljewa Equation for the thermal conductivity for gas mixtures of n elements at low pressure.

For nonpolar gas mixtures errors will generally be less than 3 to 4%. For mixtures of nonpolar-polar and polar-polar gases, errors greater than 5 to 8% may be expected. For mixtures in which the sizes and polarities of the constituent molecules are not greatly different, the thermal conductivity can be estimated satisfactorily by a mole fraction average of the pure component conductivities.

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

Inputs

NameDescription
y[:]Mole fraction of the components in the gas mixture [mol/mol]
TTemperature [K]
Tc[size(y, 1)]Critical temperatures [K]
Pc[size(y, 1)]Critical pressures [Pa]
M[size(y, 1)]Molecular weights [kg/mol]
lambda[size(y, 1)]Thermal conductivities of the pure gases [W/(m.K)]

Outputs

NameDescription
lambdamThermal conductivity of the gas mixture [W/(m.K)]

Modelica.Media.IdealGases.Common.MixtureGasNasa.thermalConductivity Modelica.Media.IdealGases.Common.MixtureGasNasa.thermalConductivity

Return thermal conductivity for low pressure gas mixtures

Information

Extends from (Return thermal conductivity).

Inputs

NameDescription
stateThermodynamic state record
methodMethod to compute single component thermal conductivity

Outputs

NameDescription
lambdaThermal conductivity [W/(m.K)]

Modelica.Media.IdealGases.Common.MixtureGasNasa.isobaricExpansionCoefficient Modelica.Media.IdealGases.Common.MixtureGasNasa.isobaricExpansionCoefficient

Return isobaric expansion coefficient beta

Information

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

Inputs

NameDescription
stateThermodynamic state record

Outputs

NameDescription
betaIsobaric expansion coefficient [1/K]

Modelica.Media.IdealGases.Common.MixtureGasNasa.isothermalCompressibility Modelica.Media.IdealGases.Common.MixtureGasNasa.isothermalCompressibility

Return isothermal compressibility factor

Information

Extends from (Return overall the isothermal compressibility factor).

Inputs

NameDescription
stateThermodynamic state record

Outputs

NameDescription
kappaIsothermal compressibility [1/Pa]

Modelica.Media.IdealGases.Common.MixtureGasNasa.density_derp_T Modelica.Media.IdealGases.Common.MixtureGasNasa.density_derp_T

Return density derivative by pressure at constant temperature

Information

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

Inputs

NameDescription
stateThermodynamic state record

Outputs

NameDescription
ddpTDensity derivative w.r.t. pressure [s2/m2]

Modelica.Media.IdealGases.Common.MixtureGasNasa.density_derT_p Modelica.Media.IdealGases.Common.MixtureGasNasa.density_derT_p

Return density derivative by temperature at constant pressure

Information

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

Inputs

NameDescription
stateThermodynamic state record

Outputs

NameDescription
ddTpDensity derivative w.r.t. temperature [kg/(m3.K)]

Modelica.Media.IdealGases.Common.MixtureGasNasa.density_derX Modelica.Media.IdealGases.Common.MixtureGasNasa.density_derX

Return density derivative by mass fraction

Information

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

Inputs

NameDescription
stateThermodynamic state record

Outputs

NameDescription
dddX[nX]Derivative of density w.r.t. mass fraction [kg/m3]

Modelica.Media.IdealGases.Common.MixtureGasNasa.molarMass Modelica.Media.IdealGases.Common.MixtureGasNasa.molarMass

Return molar mass of mixture

Information

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

Inputs

NameDescription
stateThermodynamic state record

Outputs

NameDescription
MMMixture molar mass [kg/mol]

Modelica.Media.IdealGases.Common.MixtureGasNasa.T_hX Modelica.Media.IdealGases.Common.MixtureGasNasa.T_hX

Return temperature from specific enthalpy and mass fraction

Information

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

Inputs

NameDescription
hSpecific enthalpy [J/kg]
X[nX]Mass fractions of composition [kg/kg]
exclEnthFormIf true, enthalpy of formation Hf is not included in specific enthalpy h
refChoiceChoice of reference enthalpy
h_offUser defined offset for reference enthalpy, if referenceChoice = UserDefined [J/kg]

Outputs

NameDescription
TTemperature [K]

Modelica.Media.IdealGases.Common.MixtureGasNasa.T_psX Modelica.Media.IdealGases.Common.MixtureGasNasa.T_psX

Return temperature from pressure, specific entropy and mass fraction

Information

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

Inputs

NameDescription
pPressure [Pa]
sSpecific entropy [J/(kg.K)]
X[nX]Mass fractions of composition [kg/kg]

Outputs

NameDescription
TTemperature [K]

Modelica.Media.IdealGases.Common.MixtureGasNasa.specificEntropyOfpTX Modelica.Media.IdealGases.Common.MixtureGasNasa.specificEntropyOfpTX

Return specific entropy from pressure, temperature and mass fractions

Information

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

Inputs

NameDescription
pPressure [Pa]
TTemperature [K]
X[nX]Mass fractions of composition [kg/kg]

Outputs

NameDescription
sSpecific entropy [J/(kg.K)]
Automatically generated Thu Oct 1 16:08:06 2020.