Modelica.Media.Interfaces.PartialSimpleIdealGasMedium.ThermodynamicState

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Modelica.Media.Interfaces.PartialSimpleIdealGasMedium.ThermodynamicState

Thermodynamic state of ideal gas

Information

Extends from (Minimal variable set that is available as input argument to every medium function).

Modelica definition

redeclare record extends ThermodynamicState "Thermodynamic state of ideal gas" AbsolutePressure p "Absolute pressure of medium"; Temperature T "Temperature of medium"; end ThermodynamicState;

Modelica.Media.Interfaces.PartialSimpleIdealGasMedium.BaseProperties

Base properties of ideal gas

Information

This is the most simple incompressible medium model, where specific enthalpy h and specific internal energy u are only a function of temperature T and all other provided medium quantities are assumed to be constant.

Extends from .

Parameters

Type	Name	Default	Description
Advanced
Boolean	preferredMediumStates	false	= true if StateSelect.prefer shall be used for the independent property variables of the medium

Modelica definition

redeclare replaceable model extends BaseProperties(T(stateSelect=if preferredMediumStates then StateSelect.prefer else StateSelect.default), p(stateSelect=if preferredMediumStates then StateSelect.prefer else StateSelect.default)) "Base properties of ideal gas" equation assert(T >= T_min and T <= T_max, " Temperature T (= " + String(T) + " K) is not in the allowed range (" + String(T_min) + " K <= T <= " + String(T_max) + " K) required from medium model \"" + mediumName + "\". "); h = specificEnthalpy_pTX( p, T, X); u = h - R*T; R = R_gas; d = p/(R*T); MM = MM_const; state.T = T; state.p = p; end BaseProperties;

Modelica.Media.Interfaces.PartialSimpleIdealGasMedium.setState_pTX

Return thermodynamic state from p, T, and X or Xi

Information

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

Inputs

Type	Name	Default	Description
AbsolutePressure	p		Pressure [Pa]
Temperature	T		Temperature [K]
MassFraction	X[:]	reference_X	Mass fractions [kg/kg]

Outputs

Type	Name	Description
ThermodynamicState	state	Thermodynamic state record

Modelica definition

redeclare function setState_pTX "Return thermodynamic state from p, T, and X or Xi" extends Modelica.Icons.Function; input AbsolutePressure p "Pressure"; input Temperature T "Temperature"; input MassFraction X[:]=reference_X "Mass fractions"; output ThermodynamicState state "Thermodynamic state record"; algorithm state := ThermodynamicState(p=p, T=T); end setState_pTX;

Modelica.Media.Interfaces.PartialSimpleIdealGasMedium.setState_phX

Return thermodynamic state from p, h, and X or Xi

Information

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

Inputs

Type	Name	Default	Description
AbsolutePressure	p		Pressure [Pa]
SpecificEnthalpy	h		Specific enthalpy [J/kg]
MassFraction	X[:]	reference_X	Mass fractions [kg/kg]

Outputs

Type	Name	Description
ThermodynamicState	state	Thermodynamic state record

Modelica definition

redeclare function setState_phX "Return thermodynamic state from p, h, and X or Xi" extends Modelica.Icons.Function; input AbsolutePressure p "Pressure"; input SpecificEnthalpy h "Specific enthalpy"; input MassFraction X[:]=reference_X "Mass fractions"; output ThermodynamicState state "Thermodynamic state record"; algorithm state := ThermodynamicState(p=p, T=T0 + h/cp_const); end setState_phX;

Modelica.Media.Interfaces.PartialSimpleIdealGasMedium.setState_psX

Return thermodynamic state from p, s, and X or Xi

Information

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

Inputs

Type	Name	Default	Description
AbsolutePressure	p		Pressure [Pa]
SpecificEntropy	s		Specific entropy [J/(kg.K)]
MassFraction	X[:]	reference_X	Mass fractions [kg/kg]

Outputs

Type	Name	Description
ThermodynamicState	state	Thermodynamic state record

Modelica definition

redeclare replaceable function setState_psX "Return thermodynamic state from p, s, and X or Xi" extends Modelica.Icons.Function; input AbsolutePressure p "Pressure"; input SpecificEntropy s "Specific entropy"; input MassFraction X[:]=reference_X "Mass fractions"; output ThermodynamicState state "Thermodynamic state record"; algorithm state := ThermodynamicState(p=p, T=Modelica.Math.exp(s/cp_const + Modelica.Math.log(reference_T)) + R_gas*Modelica.Math.log(p/reference_p)); end setState_psX;

Modelica.Media.Interfaces.PartialSimpleIdealGasMedium.setState_dTX

Return thermodynamic state from d, T, and X or Xi

Information

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

Inputs

Type	Name	Default	Description
Density	d		Density [kg/m3]
Temperature	T		Temperature [K]
MassFraction	X[:]	reference_X	Mass fractions [kg/kg]

Outputs

Type	Name	Description
ThermodynamicState	state	Thermodynamic state record

Modelica definition

redeclare function setState_dTX "Return thermodynamic state from d, T, and X or Xi" extends Modelica.Icons.Function; input Density d "Density"; input Temperature T "Temperature"; input MassFraction X[:]=reference_X "Mass fractions"; output ThermodynamicState state "Thermodynamic state record"; algorithm state := ThermodynamicState(p=d*R_gas*T, T=T); end setState_dTX;

Modelica.Media.Interfaces.PartialSimpleIdealGasMedium.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

Type	Name	Description
Real	x	m_flow or dp
ThermodynamicState	state_a	Thermodynamic state if x > 0
ThermodynamicState	state_b	Thermodynamic state if x < 0
Real	x_small	Smooth transition in the region -x_small < x < x_small

Outputs

Type	Name	Description
ThermodynamicState	state	Smooth thermodynamic state for all x (continuous and differentiable)

Modelica definition

redeclare function extends setSmoothState "Return thermodynamic state so that it smoothly approximates: if x > 0 then state_a else state_b" algorithm state := ThermodynamicState(p=Media.Common.smoothStep( x, state_a.p, state_b.p, x_small), T=Media.Common.smoothStep( x, state_a.T, state_b.T, x_small)); end setSmoothState;

Modelica.Media.Interfaces.PartialSimpleIdealGasMedium.pressure

Return pressure of ideal gas

Information

Extends from (Return pressure).

Inputs

Type	Name	Default	Description
ThermodynamicState	state		Thermodynamic state record

Outputs

Type	Name	Description
AbsolutePressure	p	Pressure [Pa]

Modelica definition

redeclare function extends pressure "Return pressure of ideal gas" algorithm p := state.p; end pressure;

Modelica.Media.Interfaces.PartialSimpleIdealGasMedium.temperature

Return temperature of ideal gas

Information

Extends from (Return temperature).

Inputs

Type	Name	Default	Description
ThermodynamicState	state		Thermodynamic state record

Outputs

Type	Name	Description
Temperature	T	Temperature [K]

Modelica definition

redeclare function extends temperature "Return temperature of ideal gas" algorithm T := state.T; end temperature;

Modelica.Media.Interfaces.PartialSimpleIdealGasMedium.density

Return density of ideal gas

Information

Extends from (Return density).

Inputs

Type	Name	Default	Description
ThermodynamicState	state		Thermodynamic state record

Outputs

Type	Name	Description
Density	d	Density [kg/m3]

Modelica definition

redeclare function extends density "Return density of ideal gas" algorithm d := state.p/(R_gas*state.T); end density;

Modelica.Media.Interfaces.PartialSimpleIdealGasMedium.specificEnthalpy

Return specific enthalpy

Information

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

Inputs

Type	Name	Default	Description
ThermodynamicState	state		Thermodynamic state record

Outputs

Type	Name	Description
SpecificEnthalpy	h	Specific enthalpy [J/kg]

Modelica definition

redeclare function extends specificEnthalpy "Return specific enthalpy" extends Modelica.Icons.Function; algorithm h := cp_const*(state.T - T0); end specificEnthalpy;

Modelica.Media.Interfaces.PartialSimpleIdealGasMedium.specificInternalEnergy

Return specific internal energy

Information

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

Inputs

Type	Name	Default	Description
ThermodynamicState	state		Thermodynamic state record

Outputs

Type	Name	Description
SpecificEnergy	u	Specific internal energy [J/kg]

Modelica definition

redeclare function extends specificInternalEnergy "Return specific internal energy" extends Modelica.Icons.Function; algorithm u := (cp_const - R_gas)*(state.T - T0); end specificInternalEnergy;

Modelica.Media.Interfaces.PartialSimpleIdealGasMedium.specificEntropy

Return specific entropy

Information

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

Inputs

Type	Name	Default	Description
ThermodynamicState	state		Thermodynamic state record

Outputs

Type	Name	Description
SpecificEntropy	s	Specific entropy [J/(kg.K)]

Modelica definition

redeclare function extends specificEntropy "Return specific entropy" extends Modelica.Icons.Function; algorithm s := cp_const*Modelica.Math.log(state.T/T0) - R_gas*Modelica.Math.log( state.p/reference_p); end specificEntropy;

Modelica.Media.Interfaces.PartialSimpleIdealGasMedium.specificGibbsEnergy

Return specific Gibbs energy

Information

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

Inputs

Type	Name	Default	Description
ThermodynamicState	state		Thermodynamic state record

Outputs

Type	Name	Description
SpecificEnergy	g	Specific Gibbs energy [J/kg]

Modelica definition

redeclare function extends specificGibbsEnergy "Return specific Gibbs energy" extends Modelica.Icons.Function; algorithm g := cp_const*(state.T - T0) - state.T*specificEntropy(state); end specificGibbsEnergy;

Modelica.Media.Interfaces.PartialSimpleIdealGasMedium.specificHelmholtzEnergy

Return specific Helmholtz energy

Information

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

Inputs

Type	Name	Default	Description
ThermodynamicState	state		Thermodynamic state record

Outputs

Type	Name	Description
SpecificEnergy	f	Specific Helmholtz energy [J/kg]

Modelica definition

redeclare function extends specificHelmholtzEnergy "Return specific Helmholtz energy" extends Modelica.Icons.Function; algorithm f := (cp_const - R_gas)*(state.T - T0) - state.T*specificEntropy(state); end specificHelmholtzEnergy;

Modelica.Media.Interfaces.PartialSimpleIdealGasMedium.dynamicViscosity

Return dynamic viscosity

Information

Extends from (Return dynamic viscosity).

Inputs

Type	Name	Default	Description
ThermodynamicState	state		Thermodynamic state record

Outputs

Type	Name	Description
DynamicViscosity	eta	Dynamic viscosity [Pa.s]

Modelica definition

redeclare function extends dynamicViscosity "Return dynamic viscosity" algorithm eta := eta_const; end dynamicViscosity;

Modelica.Media.Interfaces.PartialSimpleIdealGasMedium.thermalConductivity

Return thermal conductivity

Information

Extends from (Return thermal conductivity).

Inputs

Type	Name	Default	Description
ThermodynamicState	state		Thermodynamic state record

Outputs

Type	Name	Description
ThermalConductivity	lambda	Thermal conductivity [W/(m.K)]

Modelica definition

redeclare function extends thermalConductivity "Return thermal conductivity" algorithm lambda := lambda_const; end thermalConductivity;

Modelica.Media.Interfaces.PartialSimpleIdealGasMedium.specificHeatCapacityCp

Return specific heat capacity at constant pressure

Information

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

Inputs

Type	Name	Default	Description
ThermodynamicState	state		Thermodynamic state record

Outputs

Type	Name	Description
SpecificHeatCapacity	cp	Specific heat capacity at constant pressure [J/(kg.K)]

Modelica definition

redeclare function extends specificHeatCapacityCp "Return specific heat capacity at constant pressure" algorithm cp := cp_const; end specificHeatCapacityCp;

Modelica.Media.Interfaces.PartialSimpleIdealGasMedium.specificHeatCapacityCv

Return specific heat capacity at constant volume

Information

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

Inputs

Type	Name	Default	Description
ThermodynamicState	state		Thermodynamic state record

Outputs

Type	Name	Description
SpecificHeatCapacity	cv	Specific heat capacity at constant volume [J/(kg.K)]

Modelica definition

redeclare function extends specificHeatCapacityCv "Return specific heat capacity at constant volume" algorithm cv := cv_const; end specificHeatCapacityCv;

Modelica.Media.Interfaces.PartialSimpleIdealGasMedium.isentropicExponent

Return isentropic exponent

Information

Extends from (Return isentropic exponent).

Inputs

Type	Name	Default	Description
ThermodynamicState	state		Thermodynamic state record

Outputs

Type	Name	Description
IsentropicExponent	gamma	Isentropic exponent [1]

Modelica definition

redeclare function extends isentropicExponent "Return isentropic exponent" algorithm gamma := cp_const/cv_const; end isentropicExponent;

Modelica.Media.Interfaces.PartialSimpleIdealGasMedium.velocityOfSound

Return velocity of sound

Information

Extends from (Return velocity of sound).

Inputs

Type	Name	Default	Description
ThermodynamicState	state		Thermodynamic state record

Outputs

Type	Name	Description
VelocityOfSound	a	Velocity of sound [m/s]

Modelica definition

redeclare function extends velocityOfSound "Return velocity of sound" algorithm a := sqrt(cp_const/cv_const*R_gas*state.T); end velocityOfSound;

Modelica.Media.Interfaces.PartialSimpleIdealGasMedium.specificEnthalpy_pTX

Return specific enthalpy from p, T, and X or Xi

Information

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

Inputs

Type	Name	Description
AbsolutePressure	p	Pressure [Pa]
Temperature	T	Temperature [K]
MassFraction	X[nX]	Mass fractions [kg/kg]

Outputs

Type	Name	Description
SpecificEnthalpy	h	Specific enthalpy at p, T, X [J/kg]

Modelica definition

redeclare function specificEnthalpy_pTX "Return specific enthalpy from p, T, and X or Xi" extends Modelica.Icons.Function; input AbsolutePressure p "Pressure"; input Temperature T "Temperature"; input MassFraction X[nX] "Mass fractions"; output SpecificEnthalpy h "Specific enthalpy at p, T, X"; algorithm h := cp_const*(T - T0); end specificEnthalpy_pTX;

Modelica.Media.Interfaces.PartialSimpleIdealGasMedium.temperature_phX

Return temperature from p, h, and X or Xi

Information

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

Inputs

Type	Name	Description
AbsolutePressure	p	Pressure [Pa]
SpecificEnthalpy	h	Specific enthalpy [J/kg]
MassFraction	X[nX]	Mass fractions [kg/kg]

Outputs

Type	Name	Description
Temperature	T	Temperature [K]

Modelica definition

redeclare function temperature_phX "Return temperature from p, h, and X or Xi" extends Modelica.Icons.Function; input AbsolutePressure p "Pressure"; input SpecificEnthalpy h "Specific enthalpy"; input MassFraction X[nX] "Mass fractions"; output Temperature T "Temperature"; algorithm T := h/cp_const + T0; end temperature_phX;

Modelica.Media.Interfaces.PartialSimpleIdealGasMedium.density_phX

Return density from p, h, and X or Xi

Information

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

Inputs

Type	Name	Description
AbsolutePressure	p	Pressure [Pa]
SpecificEnthalpy	h	Specific enthalpy [J/kg]
MassFraction	X[nX]	Mass fractions [kg/kg]

Outputs

Type	Name	Description
Density	d	Density [kg/m3]

Modelica definition

redeclare function density_phX "Return density from p, h, and X or Xi" extends Modelica.Icons.Function; input AbsolutePressure p "Pressure"; input SpecificEnthalpy h "Specific enthalpy"; input MassFraction X[nX] "Mass fractions"; output Density d "Density"; algorithm d := density(setState_phX( p, h, X)); end density_phX;

Modelica.Media.Interfaces.PartialSimpleIdealGasMedium.isentropicEnthalpy

Return isentropic enthalpy

Information

Extends from (Return isentropic enthalpy).

Inputs

Type	Name	Default	Description
AbsolutePressure	p_downstream		Downstream pressure [Pa]
ThermodynamicState	refState		Reference state for entropy

Outputs

Type	Name	Description
SpecificEnthalpy	h_is	Isentropic enthalpy [J/kg]

Modelica definition

redeclare function extends isentropicEnthalpy "Return isentropic enthalpy" algorithm /* s = cp_const*log(refState.T/T0) - R_gas*log(refState.p/reference_p) = cp_const*log(state.T/T0) - R_gas*log(p_downstream/reference_p) log(state.T) = log(refState.T) + (R_gas/cp_const)*(log(p_downstream/reference_p) - log(refState.p/reference_p)) = log(refState.T) + (R_gas/cp_const)*log(p_downstream/refState.p) = log(refState.T) + log( (p_downstream/refState.p)^(R_gas/cp_const) ) = log( refState.T*(p_downstream/refState.p)^(R_gas/cp_const) ) state.T = refstate.T*(p_downstream/refstate.p)^(R_gas/cp_const) */ h_is := cp_const*(refState.T*(p_downstream/refState.p)^(R_gas/cp_const) - T0); end isentropicEnthalpy;

Modelica.Media.Interfaces.PartialSimpleIdealGasMedium.isobaricExpansionCoefficient

Returns overall the isobaric expansion coefficient beta

Information

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

Inputs

Type	Name	Default	Description
ThermodynamicState	state		Thermodynamic state record

Outputs

Type	Name	Description
IsobaricExpansionCoefficient	beta	Isobaric expansion coefficient [1/K]

Modelica definition

redeclare function extends isobaricExpansionCoefficient "Returns overall the isobaric expansion coefficient beta" algorithm /* beta = 1/v * der(v,T), with v = 1/d, at constant pressure p: v = R*T/p der(v,T) = R/p beta = p/(R*T)*R/p = 1/T */ beta := 1/state.T; end isobaricExpansionCoefficient;

Modelica.Media.Interfaces.PartialSimpleIdealGasMedium.isothermalCompressibility

Returns overall the isothermal compressibility factor

Information

Extends from (Return overall the isothermal compressibility factor).

Inputs

Type	Name	Default	Description
ThermodynamicState	state		Thermodynamic state record

Outputs

Type	Name	Description
IsothermalCompressibility	kappa	Isothermal compressibility [1/Pa]

Modelica definition

redeclare function extends isothermalCompressibility "Returns overall the isothermal compressibility factor" algorithm /* kappa = - 1/v * der(v,p), with v = 1/d at constant temperature T. v = R*T/p der(v,T) = -R*T/p^2 kappa = p/(R*T)*R*T/p^2 = 1/p */ kappa := 1/state.p; end isothermalCompressibility;

Modelica.Media.Interfaces.PartialSimpleIdealGasMedium.density_derp_T

Returns the partial derivative of density with respect to pressure at constant temperature

Information

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

Inputs

Type	Name	Default	Description
ThermodynamicState	state		Thermodynamic state record

Outputs

Type	Name	Description
DerDensityByPressure	ddpT	Density derivative w.r.t. pressure [s2/m2]

Modelica definition

redeclare function extends density_derp_T "Returns the partial derivative of density with respect to pressure at constant temperature" algorithm /* d = p/(R*T) ddpT = 1/(R*T) */ ddpT := 1/(R_gas*state.T); end density_derp_T;

Modelica.Media.Interfaces.PartialSimpleIdealGasMedium.density_derT_p

Returns the partial derivative of density with respect to temperature at constant pressure

Information

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

Inputs

Type	Name	Default	Description
ThermodynamicState	state		Thermodynamic state record

Outputs

Type	Name	Description
DerDensityByTemperature	ddTp	Density derivative w.r.t. temperature [kg/(m3.K)]

Modelica definition

redeclare function extends density_derT_p "Returns the partial derivative of density with respect to temperature at constant pressure" algorithm /* d = p/(R*T) ddpT = -p/(R*T^2) */ ddTp := -state.p/(R_gas*state.T*state.T); end density_derT_p;

Modelica.Media.Interfaces.PartialSimpleIdealGasMedium.density_derX

Returns the partial derivative of density with respect to mass fractions at constant pressure and temperature

Information

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

Inputs

Type	Name	Default	Description
ThermodynamicState	state		Thermodynamic state record

Outputs

Type	Name	Description
Density	dddX[nX]	Derivative of density w.r.t. mass fraction [kg/m3]

Modelica definition

redeclare function extends density_derX "Returns the partial derivative of density with respect to mass fractions at constant pressure and temperature" algorithm dddX := fill(0, nX); end density_derX;

Modelica.Media.Interfaces.PartialSimpleIdealGasMedium.molarMass

Returns the molar mass of the medium

Information

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

Inputs

Type	Name	Default	Description
ThermodynamicState	state		Thermodynamic state record

Outputs

Type	Name	Description
MolarMass	MM	Mixture molar mass [kg/mol]

Modelica definition

redeclare function extends molarMass "Returns the molar mass of the medium" algorithm MM := MM_const; end molarMass;

Automatically generated Mon Jul 13 14:36:35 2015.