WOLFRAM SYSTEM MODELER

R134a_ph

Medium model for R134a and p,h as states

Package Contents

	SaturationProperties
	ThermodynamicState Thermodynamic state
	BaseProperties Base properties of R134a
	setState_phX Set state for pressure and specific enthalpy (X not used since single substance)
	setState_dTX Set state for density and temperature (X not used since single substance)
	setState_psX Set state for pressure and specific entropy (X not used since single substance)
	setState_pTX Set state for pressure and temperature (X not used since single substance)
	setBubbleState Return the thermodynamic state on the bubble line
	setDewState Return the thermodynamic state on the dew line
	density_ph Density as function of pressure and specific enthalpy
	density Density as function of pressure and specific enthalpy \| use setState_phX function for input
	temperature_ph Temperature as function of pressure and specific enthalpy
	temperature Temperature as function of pressure and specific enthalpy \| use setState_phX function for input
	pressure Pressure w.r.t. thermodynamic state
	specificInternalEnergy Specific internal energy w.r.t. thermodynamic state
	specificEnthalpy Specific enthalpy w.r.t. thermodynamic state \| use setState_phX function for input
	specificEntropy Specific entropy w.r.t. thermodynamic state \| use setState_phX function for input if necessary
	saturationTemperature Saturation temperature in two-phase region
	saturationTemperature_derp Derivative of saturation temperature in two-phase region
	saturationTemperature_der_p Time derivative of saturation temperature in two-phase region
	bubbleDensity Density of liquid phase w.r.t. saturation pressure \| use setSat_p function for input
	dBubbleDensity_dPressure Derivative of liquid density in two-phase region w.r.t. pressure
	dBubbleDensity_dPressure_der_sat Time derivative of liquid density in two-phase region w.r.t. pressure
	dewDensity Density of vapor phase w.r.t. saturation pressure \| use setSat_p function for input
	dDewDensity_dPressure Derivative of vapor density in two-phase region w.r.t. pressure
	dDewDensity_dPressure_der_sat Time derivative of vapor density in two-phase region w.r.t. pressure
	bubbleEnthalpy Specific enthalpy of liquid phase w.r.t. saturation pressure \| use setSat_p function for input
	dBubbleEnthalpy_dPressure Derivative of liquid specific enthalpy in two-phase region w.r.t. pressure
	dBubbleEnthalpy_dPressure_der_sat Time derivative of liquid specific enthalpy in two-phase region w.r.t. pressure
	dewEnthalpy Specific enthalpy of vapor phase w.r.t. saturation pressure \| use setSat_p function for input
	dDewEnthalpy_dPressure Derivative of vapor specific enthalpy in two-phase region w.r.t. pressure
	dDewEnthalpy_dPressure_der_sat Time derivative of vapor specific enthalpy in two-phase region w.r.t. pressure
	dewEntropy Specific entropy of vapor phase w.r.t. saturation pressure \| use setSat_p function for input
	dDewEntropy_dPressure Derivative of vapor specific entropy in two-phase region w.r.t. pressure \| use setState_phX function for input
	dDewEntropy_dPressure_der_sat Time derivative of vapor specific entropy in two-phase region w.r.t. pressure \| use setState_phX function for input
	bubbleEntropy Specific entropy of liquid phase w.r.t. saturation pressure \| use setSat_p function for input
	dBubbleEntropy_dPressure Derivative of liquid specific entropy in two-phase region w.r.t. pressure \| use setState_phX function for input
	dBubbleEntropy_dPressure_der_sat Time derivative of liquid specific entropy in two-phase region w.r.t. pressure \| use setState_phX function for input
	saturationPressure Saturation pressure w.r.t. temperature
	specificHeatCapacityCp Specific heat capacity at constant pressure \| turns infinite in two-phase region! \| use setState_phX function for input
	specificHeatCapacityCv Specific heat capacity at constant volume \| use setState_phX function for input
	dynamicViscosity Dynamic viscosity w.r.t. temperature and density \| use setState_phX function for input
	thermalConductivity Thermal conductivity w.r.t. thermodynamic state \| use setState_phX function for input
	surfaceTension Surface tension as a function of temperature (below critical point)
	velocityOfSound Velocity of sound w.r.t. thermodynamic state (only valid for one-phase)
	isothermalCompressibility Isothermal compressibility w.r.t. thermodynamic state (only valid for one-phase)
	isobaricExpansionCoefficient Isobaric expansion coefficient w.r.t. thermodynamic state (only valid for one-phase)
	isentropicExponent Isentropic exponent gamma w.r.t. thermodynamic state \| not defined in two-phase region \| use setState_phX function for input
	specificGibbsEnergy Specific gibbs energy w.r.t. thermodynamic state
	specificHelmholtzEnergy Helmholtz energy w.r.t. thermodynamic state
	density_derh_p Density derivative by specific enthalpy \| use setState_phX function for input
	density_derp_h Density derivative by pressure \| use setState_phX function for input
	isentropicEnthalpy Isentropic enthalpy of downstream pressure and upstream thermodynamic state (specific entropy)
	derivsOf_ph Derivatives required for inversion of temperature and density functions
	dt_ph Density and temperature w.r.t. pressure and specific enthalpy
	dtofphOnePhase Density and temperature w.r.t. pressure and specific enthalpy in one-phase region
	dtofpsOnePhase Inverse iteration in one phase region (d,T) = f(p,s)
	f_R134a Calculation of helmholtz derivatives by density and temperature
	fid_R134a Helmholtz coefficients of ideal part
	fres_R134a Calculation of helmholtz derivatives
	getPhase_ph Number of phases by pressure and specific enthalpy
	getPhase_ps Number of phases by pressure and entropy
	hofpsTwoPhase Isentropic specific enthalpy in two phase region h(p,s)
	R134a_liqofdT Properties on liquid boundary phase
	R134a_vapofdT Properties on vapor boundary phase
	rho_ph_der Time derivative function of density_ph
	rho_props_ph Density as function of pressure and specific enthalpy
	T_ph_der Time derivative function of T_ph
	T_props_ph Temperature as function of pressure and specific enthalpy
	setSmoothState Smooth transition function between state_a and state_b
	dofpT Compute d for given p and T
	hofpT Compute h for given p and T
	phaseBoundaryAssert Assert function for checking threshold to phase boundary

Package Constants (27)

ThermoStates	Value: Modelica.Media.Interfaces.Choices.IndependentVariables.ph Type: IndependentVariables Description: Enumeration type for independent variables
mediumName	Value: "R134a_ph" Type: String Description: Name of the medium
substanceNames	Value: {"tetrafluoroethane"} Type: String[:] Description: Names of the mixture substances. Set substanceNames={mediumName} if only one substance.
extraPropertiesNames	Value: fill("", 0) Type: String[:] Description: Names of the additional (extra) transported properties. Set extraPropertiesNames=fill("",0) if unused
singleState	Value: false Type: Boolean Description: = true, if u and d are not a function of pressure
reducedX	Value: true Type: Boolean Description: = true if medium contains the equation sum(X) = 1.0; set reducedX=true if only one substance (see docu for details)
fixedX	Value: true Type: Boolean Description: = true if medium contains the equation X = reference_X
reference_p	Value: 101325 Type: AbsolutePressure (Pa) Description: Reference pressure of Medium: default 1 atmosphere
reference_T	Value: 298.15 Type: Temperature (K) Description: Reference temperature of Medium: default 25 deg Celsius
reference_X	Value: fill(1 / nX, nX) Type: MassFraction[nX] (kg/kg) Description: Default mass fractions of medium
p_default	Value: 101325 Type: AbsolutePressure (Pa) Description: Default value for pressure of medium (for initialization)
T_default	Value: Modelica.Units.Conversions.from_degC(20) Type: Temperature (K) Description: Default value for temperature of medium (for initialization)
h_default	Value: 420e3 Type: SpecificEnthalpy (J/kg) Description: Default value for specific enthalpy of medium (for initialization)
X_default	Value: reference_X Type: MassFraction[nX] (kg/kg) Description: Default value for mass fractions of medium (for initialization)
C_default	Value: fill(0, nC) Type: ExtraProperty[nC] Description: Default value for trace substances of medium (for initialization)
nS	Value: size(substanceNames, 1) Type: Integer Description: Number of substances
nX	Value: nS Type: Integer Description: Number of mass fractions
nXi	Value: if fixedX then 0 else if reducedX then nS - 1 else nS Type: Integer Description: Number of structurally independent mass fractions (see docu for details)
nC	Value: size(extraPropertiesNames, 1) Type: Integer Description: Number of extra (outside of standard mass-balance) transported properties
C_nominal	Value: 1.0e-6 * ones(nC) Type: Real[nC] Description: Default for the nominal values for the extra properties
smoothModel	Value: false Type: Boolean Description: True if the (derived) model should not generate state events
onePhase	Value: false Type: Boolean Description: True if the (derived) model should never be called with two-phase inputs
fluidConstants	Value: r134aConstants Type: FluidConstants[nS] Description: Constant data for the fluid
ph_explicit	Value: true Type: Boolean
dT_explicit	Value: false Type: Boolean
r134aLimits	Value: Type: FluidLimits[1] Description: Validity limits for fluid model
r134aConstants	Value: Type: FluidConstants[1] Description: Extended fluid constants

Information

This information is part of the Modelica Standard Library maintained by the Modelica Association.

Calculation of fluid properties for Tetrafluoroethane (R134a) in the fluid region of 0.0039 bar (Triple pressure) to 700 bar and 169.85 Kelvin (Triple temperature) to 455 Kelvin.

Restriction

The functions provided by this package shall be used inside of the restricted limits according to the referenced literature.

0.0039 bar ≤ p ≤ 700 bar
169.85 Kelvin ≤ T ≤ 455 Kelvin
explicit for pressure and specific enthalpy

References

Baehr, H.D. and Tillner-Roth, R.:: Thermodynamic Properties of Environmentally Acceptable Refrigerants - Equations of State and Tables for Ammonia, R22, R134a, R152a, and R123. Springer-Verlag, Berlin (Germany), 1994.

Klein, McLinden and Laesecke:: An improved extended corresponding states method for estimation of viscosity of pure refrigerants and mixtures. Int. J. Refrig., Vol. 20, No.3, pp. 208-217, 1997.

McLinden, Klein. and Perkins:: An extended corresponding states model for the thermal conductivity of refrigerants and refrigerant mixtures. Int. J. Refrig., 23 (2000) 43-63.

Okada and Higashi:: Surface tension correlation of HFC-134a and HCFC-123. Proceedings of the Joint Meeting of IIR Commissions B1, B2, E1, and E2, Padua, Italy, pp. 541-548, 1994.

Wolfram Language

In[1]:=

SystemModel["Modelica.Media.R134a.R134a_ph"]

Out[1]:=

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