Modelica.Media.Interfaces.PartialMedium.FluidConstants

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Modelica.Media.Interfaces.PartialMedium.FluidConstants

Critical, triple, molecular and other standard data of fluid

Modelica definition

replaceable record FluidConstants = Modelica.Media.Interfaces.Types.Basic.FluidConstants "Critical, triple, molecular and other standard data of fluid";

Modelica.Media.Interfaces.PartialMedium.prandtlNumber

Return the Prandtl number

Information

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

Inputs

Type	Name	Default	Description
ThermodynamicState	state		Thermodynamic state record

Outputs

Type	Name	Description
PrandtlNumber	Pr	Prandtl number [1]

Modelica definition

replaceable function prandtlNumber "Return the Prandtl number" extends Modelica.Icons.Function; input ThermodynamicState state "Thermodynamic state record"; output PrandtlNumber Pr "Prandtl number"; algorithm Pr := dynamicViscosity(state)*specificHeatCapacityCp(state)/ thermalConductivity(state); end prandtlNumber;

Modelica.Media.Interfaces.PartialMedium.specificEntropy

Return specific entropy

Information

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

Inputs

Type	Name	Default	Description
ThermodynamicState	state		Thermodynamic state record

Outputs

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

Modelica definition

replaceable partial function specificEntropy "Return specific entropy" extends Modelica.Icons.Function; input ThermodynamicState state "Thermodynamic state record"; output SpecificEntropy s "Specific entropy"; end specificEntropy;

Modelica.Media.Interfaces.PartialMedium.specificGibbsEnergy

Return specific Gibbs energy

Information

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

Inputs

Type	Name	Default	Description
ThermodynamicState	state		Thermodynamic state record

Outputs

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

Modelica definition

replaceable partial function specificGibbsEnergy "Return specific Gibbs energy" extends Modelica.Icons.Function; input ThermodynamicState state "Thermodynamic state record"; output SpecificEnergy g "Specific Gibbs energy"; end specificGibbsEnergy;

Modelica.Media.Interfaces.PartialMedium.specificHelmholtzEnergy

Return specific Helmholtz energy

Information

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

Inputs

Type	Name	Default	Description
ThermodynamicState	state		Thermodynamic state record

Outputs

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

Modelica definition

replaceable partial function specificHelmholtzEnergy "Return specific Helmholtz energy" extends Modelica.Icons.Function; input ThermodynamicState state "Thermodynamic state record"; output SpecificEnergy f "Specific Helmholtz energy"; end specificHelmholtzEnergy;

Modelica.Media.Interfaces.PartialMedium.heatCapacity_cp

Alias for deprecated name

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

function heatCapacity_cp = specificHeatCapacityCp "Alias for deprecated name";

Modelica.Media.Interfaces.PartialMedium.heatCapacity_cv

Alias for deprecated name

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

function heatCapacity_cv = specificHeatCapacityCv "Alias for deprecated name";

Modelica.Media.Interfaces.PartialMedium.isentropicEnthalpy

Return isentropic enthalpy

Information

This function computes an isentropic state transformation:

A medium is in a particular state, refState.
The enthalpy at another state (h_is) shall be computed under the assumption that the state transformation from refState to h_is is performed with a change of specific entropy ds = 0 and the pressure of state h_is is p_downstream and the composition X upstream and downstream is assumed to be the same.

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

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

replaceable partial function isentropicEnthalpy "Return isentropic enthalpy" extends Modelica.Icons.Function; input AbsolutePressure p_downstream "Downstream pressure"; input ThermodynamicState refState "Reference state for entropy"; output SpecificEnthalpy h_is "Isentropic enthalpy"; end isentropicEnthalpy;

Modelica.Media.Interfaces.PartialMedium.isobaricExpansionCoefficient

Return overall the isobaric expansion coefficient beta

Information

beta is defined as  1/v * der(v,T), with v = 1/d, at constant pressure p.

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

Inputs

Type	Name	Default	Description
ThermodynamicState	state		Thermodynamic state record

Outputs

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

Modelica definition

replaceable partial function isobaricExpansionCoefficient "Return overall the isobaric expansion coefficient beta" extends Modelica.Icons.Function; input ThermodynamicState state "Thermodynamic state record"; output IsobaricExpansionCoefficient beta "Isobaric expansion coefficient"; end isobaricExpansionCoefficient;

Modelica.Media.Interfaces.PartialMedium.beta

Alias for isobaricExpansionCoefficient for user convenience

Inputs

Type	Name	Default	Description
ThermodynamicState	state		Thermodynamic state record

Outputs

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

Modelica definition

function beta = isobaricExpansionCoefficient "Alias for isobaricExpansionCoefficient for user convenience";

Modelica.Media.Interfaces.PartialMedium.isothermalCompressibility

Return overall the isothermal compressibility factor

Information


kappa is defined as - 1/v * der(v,p), with v = 1/d at constant temperature T.

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

Inputs

Type	Name	Default	Description
ThermodynamicState	state		Thermodynamic state record

Outputs

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

Modelica definition

replaceable partial function isothermalCompressibility "Return overall the isothermal compressibility factor" extends Modelica.Icons.Function; input ThermodynamicState state "Thermodynamic state record"; output SI.IsothermalCompressibility kappa "Isothermal compressibility"; end isothermalCompressibility;

Modelica.Media.Interfaces.PartialMedium.kappa

Alias of isothermalCompressibility for user convenience

Inputs

Type	Name	Default	Description
ThermodynamicState	state		Thermodynamic state record

Outputs

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

Modelica definition

function kappa = isothermalCompressibility "Alias of isothermalCompressibility for user convenience";

Modelica.Media.Interfaces.PartialMedium.density_derp_h

Return density derivative w.r.t. pressure at const specific enthalpy

Information

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

Inputs

Type	Name	Default	Description
ThermodynamicState	state		Thermodynamic state record

Outputs

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

Modelica definition

replaceable partial function density_derp_h "Return density derivative w.r.t. pressure at const specific enthalpy" extends Modelica.Icons.Function; input ThermodynamicState state "Thermodynamic state record"; output DerDensityByPressure ddph "Density derivative w.r.t. pressure"; end density_derp_h;

Modelica.Media.Interfaces.PartialMedium.density_derh_p

Return density derivative w.r.t. specific enthalpy at constant pressure

Information

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

Inputs

Type	Name	Default	Description
ThermodynamicState	state		Thermodynamic state record

Outputs

Type	Name	Description
DerDensityByEnthalpy	ddhp	Density derivative w.r.t. specific enthalpy [kg.s2/m5]

Modelica definition

replaceable partial function density_derh_p "Return density derivative w.r.t. specific enthalpy at constant pressure" extends Modelica.Icons.Function; input ThermodynamicState state "Thermodynamic state record"; output DerDensityByEnthalpy ddhp "Density derivative w.r.t. specific enthalpy"; end density_derh_p;

Modelica.Media.Interfaces.PartialMedium.density_derp_T

Return density derivative w.r.t. pressure at const temperature

Information

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

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

replaceable partial function density_derp_T "Return density derivative w.r.t. pressure at const temperature" extends Modelica.Icons.Function; input ThermodynamicState state "Thermodynamic state record"; output DerDensityByPressure ddpT "Density derivative w.r.t. pressure"; end density_derp_T;

Modelica.Media.Interfaces.PartialMedium.density_derT_p

Return density derivative w.r.t. temperature at constant pressure

Information

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

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

replaceable partial function density_derT_p "Return density derivative w.r.t. temperature at constant pressure" extends Modelica.Icons.Function; input ThermodynamicState state "Thermodynamic state record"; output DerDensityByTemperature ddTp "Density derivative w.r.t. temperature"; end density_derT_p;

Modelica.Media.Interfaces.PartialMedium.density_derX

Return density derivative w.r.t. mass fraction

Information

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

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

replaceable partial function density_derX "Return density derivative w.r.t. mass fraction" extends Modelica.Icons.Function; input ThermodynamicState state "Thermodynamic state record"; output Density[nX] dddX "Derivative of density w.r.t. mass fraction"; end density_derX;

Modelica.Media.Interfaces.PartialMedium.molarMass

Return the molar mass of the medium

Information

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

Inputs

Type	Name	Default	Description
ThermodynamicState	state		Thermodynamic state record

Outputs

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

Modelica definition

replaceable partial function molarMass "Return the molar mass of the medium" extends Modelica.Icons.Function; input ThermodynamicState state "Thermodynamic state record"; output MolarMass MM "Mixture molar mass"; end molarMass;

Modelica.Media.Interfaces.PartialMedium.specificEntropy_pTX

Return specific enthalpy 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
SpecificEntropy	s	Specific entropy [J/(kg.K)]

Modelica definition

replaceable function specificEntropy_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[:]=reference_X "Mass fractions"; output SpecificEntropy s "Specific entropy"; algorithm s := specificEntropy(setState_pTX( p, T, X)); end specificEntropy_pTX;

Modelica.Media.Interfaces.PartialMedium.density_pTX

Return density 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[:]	Mass fractions [kg/kg]

Outputs

Type	Name	Description
Density	d	Density [kg/m3]

Modelica definition

replaceable function density_pTX "Return density from p, T, and X or Xi" extends Modelica.Icons.Function; input AbsolutePressure p "Pressure"; input Temperature T "Temperature"; input MassFraction X[:] "Mass fractions"; output Density d "Density"; algorithm d := density(setState_pTX( p, T, X)); end density_pTX;

Modelica.Media.Interfaces.PartialMedium.temperature_psX

Return temperature 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
Temperature	T	Temperature [K]

Modelica definition

replaceable function temperature_psX "Return temperature 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 Temperature T "Temperature"; algorithm T := temperature(setState_psX( p, s, X)); end temperature_psX;

Modelica.Media.Interfaces.PartialMedium.density_psX

Return density 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
Density	d	Density [kg/m3]

Modelica definition

replaceable function density_psX "Return density 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 Density d "Density"; algorithm d := density(setState_psX( p, s, X)); end density_psX;

Modelica.Media.Interfaces.PartialMedium.specificEnthalpy_psX

Return specific enthalpy 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
SpecificEnthalpy	h	Specific enthalpy [J/kg]

Modelica definition

replaceable function specificEnthalpy_psX "Return specific enthalpy 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 SpecificEnthalpy h "Specific enthalpy"; algorithm h := specificEnthalpy(setState_psX( p, s, X)); end specificEnthalpy_psX;

Modelica.Media.Interfaces.PartialMedium.setState_psX

Return thermodynamic state as function of p, s and composition 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

replaceable partial function setState_psX "Return thermodynamic state as function of p, s and composition 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"; end setState_psX;

Modelica.Media.Interfaces.PartialMedium.setSmoothState

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

Information

This function is used to approximate the equation

    state = if x > 0 then state_a else state_b;

by a smooth characteristic, so that the expression is continuous and differentiable:

   state := smooth(1, if x >  x_small then state_a else
                      if x < -x_small then state_b else f(state_a, state_b));

This is performed by applying function Media.Common.smoothStep(..) on every element of the thermodynamic state record.

If mass fractions X[:] are approximated with this function then this can be performed for all nX mass fractions, instead of applying it for nX-1 mass fractions and computing the last one by the mass fraction constraint sum(X)=1. The reason is that the approximating function has the property that sum(state.X) = 1, provided sum(state_a.X) = sum(state_b.X) = 1. This can be shown by evaluating the approximating function in the abs(x) < x_small region (otherwise state.X is either state_a.X or state_b.X):

    X[1]  = smoothStep(x, X_a[1] , X_b[1] , x_small);
    X[2]  = smoothStep(x, X_a[2] , X_b[2] , x_small);
       ...
    X[nX] = smoothStep(x, X_a[nX], X_b[nX], x_small);

    X[1]  = c*(X_a[1]  - X_b[1])  + (X_a[1]  + X_b[1])/2
    X[2]  = c*(X_a[2]  - X_b[2])  + (X_a[2]  + X_b[2])/2;
       ...
    X[nX] = c*(X_a[nX] - X_b[nX]) + (X_a[nX] + X_b[nX])/2;
    c     = (x/x_small)*((x/x_small)^2 - 3)/4

Summing all mass fractions together results in

    sum(X) = c*(sum(X_a) - sum(X_b)) + (sum(X_a) + sum(X_b))/2
           = c*(1 - 1) + (1 + 1)/2
           = 1

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

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

replaceable partial function setSmoothState "Return thermodynamic state so that it smoothly approximates: if x > 0 then state_a else state_b" extends Modelica.Icons.Function; input Real x "m_flow or dp"; input ThermodynamicState state_a "Thermodynamic state if x > 0"; input ThermodynamicState state_b "Thermodynamic state if x < 0"; input Real x_small(min=0) "Smooth transition in the region -x_small < x < x_small"; output ThermodynamicState state "Smooth thermodynamic state for all x (continuous and differentiable)"; end setSmoothState;

Modelica.Media.Interfaces.PartialMedium.isentropicExponent

Return isentropic exponent

Information

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

Inputs

Type	Name	Default	Description
ThermodynamicState	state		Thermodynamic state record

Outputs

Type	Name	Description
IsentropicExponent	gamma	Isentropic exponent [1]

Modelica definition

replaceable partial function isentropicExponent "Return isentropic exponent" extends Modelica.Icons.Function; input ThermodynamicState state "Thermodynamic state record"; output IsentropicExponent gamma "Isentropic exponent"; end isentropicExponent;

Modelica.Media.Interfaces.PartialMedium.velocityOfSound

Return velocity of sound

Information

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

Inputs

Type	Name	Default	Description
ThermodynamicState	state		Thermodynamic state record

Outputs

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

Modelica definition

replaceable partial function velocityOfSound "Return velocity of sound" extends Modelica.Icons.Function; input ThermodynamicState state "Thermodynamic state record"; output VelocityOfSound a "Velocity of sound"; end velocityOfSound;

Modelica.Media.Interfaces.PartialMedium.specificEnthalpy_pTX

Return specific enthalpy 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
SpecificEnthalpy	h	Specific enthalpy [J/kg]

Modelica definition

replaceable 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[:]=reference_X "Mass fractions"; output SpecificEnthalpy h "Specific enthalpy"; algorithm h := specificEnthalpy(setState_pTX( p, T, X)); end specificEnthalpy_pTX;

Modelica.Media.Interfaces.PartialMedium.temperature_phX

Return temperature 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
Temperature	T	Temperature [K]

Modelica definition

replaceable 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[:]=reference_X "Mass fractions"; output Temperature T "Temperature"; algorithm T := temperature(setState_phX( p, h, X)); end temperature_phX;

Modelica.Media.Interfaces.PartialMedium.density_phX

Return density 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
Density	d	Density [kg/m3]

Modelica definition

replaceable 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[:]=reference_X "Mass fractions"; output Density d "Density"; algorithm d := density(setState_phX( p, h, X)); end density_phX;

Modelica.Media.Interfaces.PartialMedium.specificInternalEnergy

Return specific internal energy

Information

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

Inputs

Type	Name	Default	Description
ThermodynamicState	state		Thermodynamic state record

Outputs

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

Modelica definition

replaceable partial function specificInternalEnergy "Return specific internal energy" extends Modelica.Icons.Function; input ThermodynamicState state "Thermodynamic state record"; output SpecificEnergy u "Specific internal energy"; end specificInternalEnergy;

Automatically generated Thu Jun 19 11:07:18 2014.