Buildings.Media.Specialized.Water.ConstantProperties_pT

Package with model for liquid water with constant properties at user-provided nominal conditions

Information

Model for liquid water with constant properties at given nominal conditions.

This water model is similar to Buildings.Media.Water with regard to its complexity. It also uses constant values for properties such as density and specific heat capacity. The main difference is that the constants T_nominal and p_nominal allow for user-provided nominal condition of the water model. The constant properties will be derived for this nominal condition. The maximum allowed temperature is set at the saturation temperature for the given nominal pressure p_nominal.

Assumptions and limitations

The nominal values for the constant medium properties are calculated using the Modelica.Media.Water.WaterIF97_base model.

Typical use and important parameters

A model using this medium model can set the nominal conditions e.g. by defining

  package Medium = Buildings.Media.Specialized.Water.ConstantProperties_pT(
    T_nominal=273.15+100,
    p_nominal=5e5);

Extends from Buildings.Media.Water (Package with model for liquid water with constant density).

Package Content

Name Description
T_max_nominal=Modelica.Media.Water.IF97_Utilities.BaseIF97.Basic.tsat(p_nominal) Maximum temperature valid for medium model
T_nominal=273.15 + 20 Nominal temperature for calculation of water properties
a_nominal=Modelica.Media.Water.IF97_Utilities.velocityOfSound_pT(p_nominal, T_nominal) Constant velocity of sound
cp_nominal=Modelica.Media.Water.IF97_Utilities.cp_pT(p_nominal, T_nominal) Specific heat capacity at nominal water conditions
d_nominal=Modelica.Media.Water.IF97_Utilities.rho_pT(p_nominal, T_nominal) Density at nominal water conditions
eta_nominal=Modelica.Media.Water.IF97_Utilities.dynamicViscosity(d_nominal, T_nominal, p_nominal) Constant dynamic viscosity
lambda_nominal=Modelica.Media.Water.IF97_Utilities.thermalConductivity(d_nominal, T_nominal, p_nominal) Constant thermal conductivity
p_nominal=101325 Nominal pressure for calculation of water properties
Inherited
Buildings.Media.Water.BaseProperties BaseProperties Base properties
Buildings.Media.Water.enthalpyOfLiquid enthalpyOfLiquid Return the specific enthalpy of liquid
simpleWaterConstants  
cp_const=cp_nominal Constant specific heat capacity at constant pressure
cv_const=cp_const Constant specific heat capacity at constant volume
d_const=d_nominal Constant density
eta_const=eta_nominal Constant dynamic viscosity
lambda_const=lambda_nominal Constant thermal conductivity
a_const=a_nominal Constant velocity of sound
T_min=Cv.from_degC(-1) Minimum temperature valid for medium model
T_max=T_max_nominal Maximum temperature valid for medium model
T0=273.15 Zero enthalpy temperature
MM_const=0.018015268 Molar mass
fluidConstants=simpleWaterConstants Fluid constants
Modelica.Media.Interfaces.PartialSimpleMedium.ThermodynamicState ThermodynamicState Thermodynamic state
Modelica.Media.Interfaces.PartialSimpleMedium.setState_pTX setState_pTX Return thermodynamic state from p, T, and X or Xi
Modelica.Media.Interfaces.PartialSimpleMedium.setState_phX setState_phX Return thermodynamic state from p, h, and X or Xi
Modelica.Media.Interfaces.PartialSimpleMedium.setState_psX setState_psX Return thermodynamic state from p, s, and X or Xi
Modelica.Media.Interfaces.PartialSimpleMedium.setState_dTX setState_dTX Return thermodynamic state from d, T, and X or Xi
Modelica.Media.Interfaces.PartialSimpleMedium.setSmoothState setSmoothState Return thermodynamic state so that it smoothly approximates: if x > 0 then state_a else state_b
Modelica.Media.Interfaces.PartialSimpleMedium.dynamicViscosity dynamicViscosity Return dynamic viscosity
Modelica.Media.Interfaces.PartialSimpleMedium.thermalConductivity thermalConductivity Return thermal conductivity
Modelica.Media.Interfaces.PartialSimpleMedium.pressure pressure Return pressure
Modelica.Media.Interfaces.PartialSimpleMedium.temperature temperature Return temperature
Modelica.Media.Interfaces.PartialSimpleMedium.density density Return density
Modelica.Media.Interfaces.PartialSimpleMedium.specificEnthalpy specificEnthalpy Return specific enthalpy
Modelica.Media.Interfaces.PartialSimpleMedium.specificHeatCapacityCp specificHeatCapacityCp Return specific heat capacity at constant pressure
Modelica.Media.Interfaces.PartialSimpleMedium.specificHeatCapacityCv specificHeatCapacityCv Return specific heat capacity at constant volume
Modelica.Media.Interfaces.PartialSimpleMedium.isentropicExponent isentropicExponent Return isentropic exponent
Modelica.Media.Interfaces.PartialSimpleMedium.velocityOfSound velocityOfSound Return velocity of sound
Modelica.Media.Interfaces.PartialSimpleMedium.specificEnthalpy_pTX specificEnthalpy_pTX Return specific enthalpy from p, T, and X or Xi
Modelica.Media.Interfaces.PartialSimpleMedium.temperature_phX temperature_phX Return temperature from p, h, and X or Xi
Modelica.Media.Interfaces.PartialSimpleMedium.density_phX density_phX Return density from p, h, and X or Xi
Modelica.Media.Interfaces.PartialSimpleMedium.specificInternalEnergy specificInternalEnergy Return specific internal energy
Modelica.Media.Interfaces.PartialSimpleMedium.specificEntropy specificEntropy Return specific entropy
Modelica.Media.Interfaces.PartialSimpleMedium.specificGibbsEnergy specificGibbsEnergy Return specific Gibbs energy
Modelica.Media.Interfaces.PartialSimpleMedium.specificHelmholtzEnergy specificHelmholtzEnergy Return specific Helmholtz energy
Modelica.Media.Interfaces.PartialSimpleMedium.isentropicEnthalpy isentropicEnthalpy Return isentropic enthalpy
Modelica.Media.Interfaces.PartialSimpleMedium.isobaricExpansionCoefficient isobaricExpansionCoefficient Returns overall the isobaric expansion coefficient beta
Modelica.Media.Interfaces.PartialSimpleMedium.isothermalCompressibility isothermalCompressibility Returns overall the isothermal compressibility factor
Modelica.Media.Interfaces.PartialSimpleMedium.density_derp_T density_derp_T Returns the partial derivative of density with respect to pressure at constant temperature
Modelica.Media.Interfaces.PartialSimpleMedium.density_derT_p density_derT_p Returns the partial derivative of density with respect to temperature at constant pressure
Modelica.Media.Interfaces.PartialSimpleMedium.density_derX density_derX Returns the partial derivative of density with respect to mass fractions at constant pressure and temperature
Modelica.Media.Interfaces.PartialSimpleMedium.molarMass molarMass Return the molar mass of the medium
Modelica.Media.Interfaces.PartialPureSubstance.setState_pT setState_pT Return thermodynamic state from p and T
Modelica.Media.Interfaces.PartialPureSubstance.setState_ph setState_ph Return thermodynamic state from p and h
Modelica.Media.Interfaces.PartialPureSubstance.setState_ps setState_ps Return thermodynamic state from p and s
Modelica.Media.Interfaces.PartialPureSubstance.setState_dT setState_dT Return thermodynamic state from d and T
Modelica.Media.Interfaces.PartialPureSubstance.density_ph density_ph Return density from p and h
Modelica.Media.Interfaces.PartialPureSubstance.temperature_ph temperature_ph Return temperature from p and h
Modelica.Media.Interfaces.PartialPureSubstance.pressure_dT pressure_dT Return pressure from d and T
Modelica.Media.Interfaces.PartialPureSubstance.specificEnthalpy_dT specificEnthalpy_dT Return specific enthalpy from d and T
Modelica.Media.Interfaces.PartialPureSubstance.specificEnthalpy_ps specificEnthalpy_ps Return specific enthalpy from p and s
Modelica.Media.Interfaces.PartialPureSubstance.temperature_ps temperature_ps Return temperature from p and s
Modelica.Media.Interfaces.PartialPureSubstance.density_ps density_ps Return density from p and s
Modelica.Media.Interfaces.PartialPureSubstance.specificEnthalpy_pT specificEnthalpy_pT Return specific enthalpy from p and T
Modelica.Media.Interfaces.PartialPureSubstance.density_pT density_pT Return density from p and T
ThermoStates=Modelica.Media.Interfaces.Choices.IndependentVariables.pT Enumeration type for independent variables
mediumName="ConstantPropertyWater(p=" + String(p_nominal) + ",T=" + String(T_nominal) + ")" Name of the medium
substanceNames={mediumName} 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=true = true, if u and d are not a function of pressure
reducedX=true = true if medium contains the equation sum(X) = 1.0; set reducedX=true if only one substance (see docu for details)
fixedX=true = true if medium contains the equation X = reference_X
reference_p=p_nominal Reference pressure of Medium: default 1 atmosphere
reference_T=273.15 Reference temperature of Medium: default 25 deg Celsius
reference_X={1} Default mass fractions of medium
p_default=p_nominal Default value for pressure of medium (for initialization)
T_default=Modelica.SIunits.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)
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.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_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

Types and constants

  constant Modelica.SIunits.Temperature T_max_nominal=
  Modelica.Media.Water.IF97_Utilities.BaseIF97.Basic.tsat(p_nominal)
    "Maximum temperature valid for medium model";
  constant Modelica.SIunits.Temperature T_nominal = 273.15 + 20
    "Nominal temperature for calculation of water properties";
  constant Modelica.SIunits.VelocityOfSound a_nominal=
    Modelica.Media.Water.IF97_Utilities.velocityOfSound_pT(p_nominal, T_nominal)
    "Constant velocity of sound";
  constant Modelica.SIunits.SpecificHeatCapacity cp_nominal=
    Modelica.Media.Water.IF97_Utilities.cp_pT(p_nominal, T_nominal)
    "Specific heat capacity at nominal water conditions";
  constant Modelica.SIunits.Density d_nominal=
    Modelica.Media.Water.IF97_Utilities.rho_pT(p_nominal, T_nominal)
    "Density at nominal water conditions";
  constant Modelica.SIunits.DynamicViscosity eta_nominal=
   Modelica.Media.Water.IF97_Utilities.dynamicViscosity(
     d_nominal,
     T_nominal,
     p_nominal)
   "Constant dynamic viscosity";
  constant Modelica.SIunits.ThermalConductivity lambda_nominal=
    Modelica.Media.Water.IF97_Utilities.thermalConductivity(
     d_nominal,
     T_nominal,
     p_nominal)
    "Constant thermal conductivity";
  constant Modelica.SIunits.AbsolutePressure p_nominal = 101325
    "Nominal pressure for calculation of water properties";