WOLFRAM SYSTEMMODELER

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: {"tetrafluoroethan"}

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.SIunits.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]

r134aConstants

Value:

Type: FluidConstants[1]

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]:=