Water: Steam properties as defined by IAPWS/IF97 standard
Information
This model calculates medium properties
for water in the liquid, gas and two phase regions
according to the IAPWS/IF97 standard, i.e., the accepted industrial standard
and best compromise between accuracy and computation time.
For more details see
Modelica.Media.Water.IF97_Utilities. Three variable pairs can be the
independent variables of the model:
- Pressure p and specific enthalpy h are the most natural choice for general applications. This is the recommended choice for most general purpose applications, in particular for power plants.
- Pressure p and temperature T are the most natural choice for applications where water is always in the same phase, both for liquid water and steam.
- Density d and temperature T are explicit variables of the Helmholtz function in the near-critical region and can be the best choice for applications with super-critical or near-critical states.
The following quantities are always computed:
| Variable |
Unit |
Description |
| T |
K |
temperature |
| u |
J/kg |
specific internal energy |
| d |
kg/m^3 |
density |
| p |
Pa |
pressure |
| h |
J/kg |
specific enthalpy |
In some cases additional medium properties are needed.
A component that needs these optional properties has to call
one of the functions listed in
Modelica.Media.UsersGuide.MediumUsage.OptionalProperties and in
Modelica.Media.UsersGuide.MediumUsage.TwoPhase.
Many further properties can be computed. Using the well-known Bridgman's Tables, all first partial derivatives of the standard thermodynamic variables can be computed easily.
Extends from Interfaces.PartialTwoPhaseMedium (Base class for two phase medium of one substance).
Package Content
| Name |
Description |
 ThermodynamicState
|
Thermodynamic state |
| Region=0 |
Region of IF97, if known, zero otherwise |
| ph_explicit |
True if explicit in pressure and specific enthalpy |
| dT_explicit |
True if explicit in density and temperature |
| pT_explicit |
True if explicit in pressure and temperature |
 BaseProperties
|
Base properties of water |
 density_ph
|
Computes density as a function of pressure and specific enthalpy |
| temperature_ph
|
Computes temperature as a function of pressure and specific enthalpy |
| temperature_ps
|
Compute temperature from pressure and specific enthalpy |
| density_ps
|
Computes density as a function of pressure and specific enthalpy |
| pressure_dT
|
Computes pressure as a function of density and temperature |
| specificEnthalpy_dT
|
Computes specific enthalpy as a function of density and temperature |
| specificEnthalpy_pT
|
Computes specific enthalpy as a function of pressure and temperature |
| specificEnthalpy_ps
|
Computes specific enthalpy as a function of pressure and temperature |
| density_pT
|
Computes density as a function of pressure and temperature |
| setDewState
|
Set the thermodynamic state on the dew line |
| setBubbleState
|
Set the thermodynamic state on the bubble line |
| dynamicViscosity
|
Dynamic viscosity of water |
| thermalConductivity
|
Thermal conductivity of water |
| surfaceTension
|
Surface tension in two phase region of water |
| pressure
|
Return pressure of ideal gas |
| temperature
|
Return temperature of ideal gas |
| density
|
Return density of ideal gas |
 specificEnthalpy
|
Return specific enthalpy |
| specificInternalEnergy
|
Return specific internal energy |
| specificGibbsEnergy
|
Return specific Gibbs energy |
| specificHelmholtzEnergy
|
Return specific Helmholtz energy |
 specificEntropy
|
Specific entropy of water |
 specificHeatCapacityCp
|
Specific heat capacity at constant pressure of water |
| specificHeatCapacityCv
|
Specific heat capacity at constant volume of water |
| isentropicExponent
|
Return isentropic exponent |
| isothermalCompressibility
|
Isothermal compressibility of water |
| isobaricExpansionCoefficient
|
Isobaric expansion coefficient of water |
| velocityOfSound
|
Return velocity of sound as a function of the thermodynamic state record |
| isentropicEnthalpy
|
Compute h(s,p) |
| density_derh_p
|
Density derivative by specific enthalpy |
| density_derp_h
|
Density derivative by pressure |
| bubbleEnthalpy
|
Boiling curve specific enthalpy of water |
| dewEnthalpy
|
Dew curve specific enthalpy of water |
| bubbleEntropy
|
Boiling curve specific entropy of water |
| dewEntropy
|
Dew curve specific entropy of water |
| bubbleDensity
|
Boiling curve specific density of water |
| dewDensity
|
Dew curve specific density of water |
| saturationTemperature
|
Saturation temperature of water |
| saturationTemperature_derp
|
Derivative of saturation temperature w.r.t. pressure |
| saturationPressure
|
Saturation pressure of water |
| dBubbleDensity_dPressure
|
Bubble point density derivative |
| dDewDensity_dPressure
|
Dew point density derivative |
| dBubbleEnthalpy_dPressure
|
Bubble point specific enthalpy derivative |
| dDewEnthalpy_dPressure
|
Dew point specific enthalpy derivative |
| setState_dTX
|
Return thermodynamic state of water as function of d, T, and optional region |
| setState_phX
|
Return thermodynamic state of water as function of p, h, and optional region |
| setState_psX
|
Return thermodynamic state of water as function of p, s, and optional region |
| setState_pTX
|
Return thermodynamic state of water as function of p, T, and optional region |
| setSmoothState
|
Return thermodynamic state so that it smoothly approximates: if x > 0 then state_a else state_b |
| Inherited |
| smoothModel=false |
True if the (derived) model should not generate state events |
| onePhase=false |
True if the (derived) model should never be called with two-phase inputs |
| fluidConstants=waterConstants |
Constant data for the fluid |
| setSat_T
|
Return saturation property record from temperature |
| setSat_p
|
Return saturation property record from pressure |
| saturationPressure_sat
|
Return saturation temperature |
| saturationTemperature_sat
|
Return saturation temperature |
| saturationTemperature_derp_sat
|
Return derivative of saturation temperature w.r.t. pressure |
| molarMass
|
Return the molar mass of the medium |
| specificEnthalpy_pTX
|
Return specific enthalpy from pressure, temperature and mass fraction |
| temperature_phX
|
Return temperature from p, h, and X or Xi |
| density_phX
|
Return density from p, h, and X or Xi |
| temperature_psX
|
Return temperature from p, s, and X or Xi |
| density_psX
|
Return density from p, s, and X or Xi |
| specificEnthalpy_psX
|
Return specific enthalpy from p, s, and X or Xi |
| setState_pT
|
Return thermodynamic state from p and T |
| setState_ph
|
Return thermodynamic state from p and h |
| setState_ps
|
Return thermodynamic state from p and s |
| setState_dT
|
Return thermodynamic state from d and T |
| setState_px
|
Return thermodynamic state from pressure and vapour quality |
| setState_Tx
|
Return thermodynamic state from temperature and vapour quality |
| vapourQuality
|
Return vapour quality |
| ThermoStates |
Enumeration type for independent variables |
| mediumName="WaterIF97" |
Name of the medium |
| substanceNames={"water"} |
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=false |
= 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=101325 |
Reference pressure of Medium: default 1 atmosphere |
| reference_T=298.15 |
Reference temperature of Medium: default 25 deg Celsius |
| reference_X=fill(1/nX, nX) |
Default mass fractions of medium |
| p_default=101325 |
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) |
| C_default=fill(0, nC) |
Default value for trace substances 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 |
 FluidConstants
|
Critical, triple, molecular and other standard data of fluid |
 prandtlNumber
|
Return the Prandtl number |
 heatCapacity_cp
|
Alias for deprecated name |
| heatCapacity_cv
|
Alias for deprecated name |
| beta
|
Alias for isobaricExpansionCoefficient for user convenience |
| kappa
|
Alias of isothermalCompressibility for user convenience |
| density_derp_T
|
Return density derivative w.r.t. pressure at const temperature |
| density_derT_p
|
Return density derivative w.r.t. temperature at constant pressure |
| density_derX
|
Return density derivative w.r.t. mass fraction |
| specificEntropy_pTX
|
Return specific enthalpy from p, T, and X or Xi |
| density_pTX
|
Return density from p, T, and X or Xi |
 MassFlowRate
|
Type for mass flow rate with medium specific attributes |
 AbsolutePressure
|
Type for absolute pressure with medium specific attributes |
| Density
|
Type for density with medium specific attributes |
| DynamicViscosity
|
Type for dynamic viscosity with medium specific attributes |
| EnthalpyFlowRate
|
Type for enthalpy flow rate with medium specific attributes |
| MassFraction
|
Type for mass fraction with medium specific attributes |
| MoleFraction
|
Type for mole fraction with medium specific attributes |
| MolarMass
|
Type for molar mass with medium specific attributes |
| MolarVolume
|
Type for molar volume with medium specific attributes |
| IsentropicExponent
|
Type for isentropic exponent with medium specific attributes |
| SpecificEnergy
|
Type for specific energy with medium specific attributes |
| SpecificInternalEnergy
|
Type for specific internal energy with medium specific attributes |
| SpecificEnthalpy
|
Type for specific enthalpy with medium specific attributes |
| SpecificEntropy
|
Type for specific entropy with medium specific attributes |
| SpecificHeatCapacity
|
Type for specific heat capacity with medium specific attributes |
| SurfaceTension
|
Type for surface tension with medium specific attributes |
| Temperature
|
Type for temperature with medium specific attributes |
| ThermalConductivity
|
Type for thermal conductivity with medium specific attributes |
| PrandtlNumber
|
Type for Prandtl number with medium specific attributes |
| VelocityOfSound
|
Type for velocity of sound with medium specific attributes |
| ExtraProperty
|
Type for unspecified, mass-specific property transported by flow |
| CumulativeExtraProperty
|
Type for conserved integral of unspecified, mass specific property |
| ExtraPropertyFlowRate
|
Type for flow rate of unspecified, mass-specific property |
| IsobaricExpansionCoefficient
|
Type for isobaric expansion coefficient with medium specific attributes |
| DipoleMoment
|
Type for dipole moment with medium specific attributes |
| DerDensityByPressure
|
Type for partial derivative of density with respect to pressure with medium specific attributes |
| DerDensityByEnthalpy
|
Type for partial derivative of density with respect to enthalpy with medium specific attributes |
| DerEnthalpyByPressure
|
Type for partial derivative of enthalpy with respect to pressure with medium specific attributes |
| DerDensityByTemperature
|
Type for partial derivative of density with respect to temperature with medium specific attributes |
| DerTemperatureByPressure
|
Type for partial derivative of temperature with respect to pressure with medium specific attributes |
 SaturationProperties
|
Saturation properties of two phase medium |
| FluidLimits
|
Validity limits for fluid model |
 FixedPhase
|
Phase of the fluid: 1 for 1-phase, 2 for two-phase, 0 for not known, e.g., interactive use |
 Basic
|
The most basic version of a record used in several degrees of detail |
| IdealGas
|
The ideal gas version of a record used in several degrees of detail |
| TwoPhase
|
The two phase fluid version of a record used in several degrees of detail |
Thermodynamic state
Information
Extends from (Thermodynamic state of two phase medium).
Base properties of water
Information
Extends from (Base properties (p, d, T, h, u, R, MM, sat) of two phase medium).
Parameters
| Name | Description |
|---|
| Advanced |
| preferredMediumStates | = true if StateSelect.prefer shall be used for the independent property variables of the medium |
Computes density as a function of pressure and specific enthalpy
Information
Extends from Modelica.Icons.Function (Icon for functions).
Inputs
Outputs
| Name | Description |
|---|
| d | Density [kg/m3] |
Computes temperature as a function of pressure and specific enthalpy
Information
Extends from Modelica.Icons.Function (Icon for functions).
Inputs
Outputs
| Name | Description |
|---|
| T | Temperature [K] |
Compute temperature from pressure and specific enthalpy
Information
Extends from Modelica.Icons.Function (Icon for functions).
Inputs
Outputs
| Name | Description |
|---|
| T | Temperature [K] |
Computes density as a function of pressure and specific enthalpy
Information
Extends from Modelica.Icons.Function (Icon for functions).
Inputs
Outputs
| Name | Description |
|---|
| d | Density [kg/m3] |
Computes pressure as a function of density and temperature
Information
Extends from Modelica.Icons.Function (Icon for functions).
Inputs
Outputs
| Name | Description |
|---|
| p | Pressure [Pa] |
Computes specific enthalpy as a function of density and temperature
Information
Extends from Modelica.Icons.Function (Icon for functions).
Inputs
Outputs
| Name | Description |
|---|
| h | Specific enthalpy [J/kg] |
Computes specific enthalpy as a function of pressure and temperature
Information
Extends from Modelica.Icons.Function (Icon for functions).
Inputs
Outputs
| Name | Description |
|---|
| h | Specific enthalpy [J/kg] |
Computes specific enthalpy as a function of pressure and temperature
Information
Extends from Modelica.Icons.Function (Icon for functions).
Inputs
Outputs
| Name | Description |
|---|
| h | Specific enthalpy [J/kg] |
Computes density as a function of pressure and temperature
Information
Extends from Modelica.Icons.Function (Icon for functions).
Inputs
Outputs
| Name | Description |
|---|
| d | Density [kg/m3] |
Set the thermodynamic state on the dew line
Information
Extends from (Return the thermodynamic state on the dew line).
Inputs
Outputs
| Name | Description |
|---|
| state | Complete thermodynamic state info |
Set the thermodynamic state on the bubble line
Information
Extends from (Return the thermodynamic state on the bubble line).
Inputs
Outputs
| Name | Description |
|---|
| state | Complete thermodynamic state info |
Dynamic viscosity of water
Information
Extends from (Return dynamic viscosity).
Inputs
Outputs
| Name | Description |
|---|
| eta | Dynamic viscosity [Pa.s] |
Thermal conductivity of water
Information
Extends from (Return thermal conductivity).
Inputs
Outputs
| Name | Description |
|---|
| lambda | Thermal conductivity [W/(m.K)] |
Surface tension in two phase region of water
Information
Extends from (Return surface tension sigma in the two phase region).
Inputs
Outputs
| Name | Description |
|---|
| sigma | Surface tension sigma in the two phase region [N/m] |
Return pressure of ideal gas
Information
Extends from (Return pressure).
Inputs
Outputs
| Name | Description |
|---|
| p | Pressure [Pa] |
Return temperature of ideal gas
Information
Extends from (Return temperature).
Inputs
Outputs
| Name | Description |
|---|
| T | Temperature [K] |
Return density of ideal gas
Information
Extends from (Return density).
Inputs
Outputs
| Name | Description |
|---|
| d | Density [kg/m3] |
Return specific enthalpy
Information
Extends from Modelica.Icons.Function (Icon for functions), (Return specific enthalpy).
Inputs
Outputs
| Name | Description |
|---|
| h | Specific enthalpy [J/kg] |
Return specific internal energy
Information
Extends from Modelica.Icons.Function (Icon for functions), (Return specific internal energy).
Inputs
Outputs
| Name | Description |
|---|
| u | Specific internal energy [J/kg] |
Return specific Gibbs energy
Information
Extends from Modelica.Icons.Function (Icon for functions), (Return specific Gibbs energy).
Inputs
Outputs
| Name | Description |
|---|
| g | Specific Gibbs energy [J/kg] |
Return specific Helmholtz energy
Information
Extends from Modelica.Icons.Function (Icon for functions), (Return specific Helmholtz energy).
Inputs
Outputs
| Name | Description |
|---|
| f | Specific Helmholtz energy [J/kg] |
Specific entropy of water
Information
Extends from (Return specific entropy).
Inputs
Outputs
| Name | Description |
|---|
| s | Specific entropy [J/(kg.K)] |
Specific heat capacity at constant pressure of water
Information
Extends from (Return specific heat capacity at constant pressure).
Inputs
Outputs
| Name | Description |
|---|
| cp | Specific heat capacity at constant pressure [J/(kg.K)] |
Specific heat capacity at constant volume of water
Information
Extends from (Return specific heat capacity at constant volume).
Inputs
Outputs
| Name | Description |
|---|
| cv | Specific heat capacity at constant volume [J/(kg.K)] |
Return isentropic exponent
Information
Extends from (Return isentropic exponent).
Inputs
Outputs
| Name | Description |
|---|
| gamma | Isentropic exponent [1] |
Isothermal compressibility of water
Information
Extends from (Return overall the isothermal compressibility factor).
Inputs
Outputs
| Name | Description |
|---|
| kappa | Isothermal compressibility [1/Pa] |
Isobaric expansion coefficient of water
Information
Extends from (Return overall the isobaric expansion coefficient beta).
Inputs
Outputs
| Name | Description |
|---|
| beta | Isobaric expansion coefficient [1/K] |
Return velocity of sound as a function of the thermodynamic state record
Information
Extends from (Return velocity of sound).
Inputs
Outputs
| Name | Description |
|---|
| a | Velocity of sound [m/s] |
Compute h(s,p)
Information
Extends from (Return isentropic enthalpy).
Inputs
Outputs
| Name | Description |
|---|
| h_is | Isentropic enthalpy [J/kg] |
Density derivative by specific enthalpy
Information
Extends from (Return density derivative w.r.t. specific enthalpy at constant pressure).
Inputs
Outputs
| Name | Description |
|---|
| ddhp | Density derivative w.r.t. specific enthalpy [kg.s2/m5] |
Density derivative by pressure
Information
Extends from (Return density derivative w.r.t. pressure at const specific enthalpy).
Inputs
Outputs
| Name | Description |
|---|
| ddph | Density derivative w.r.t. pressure [s2/m2] |
Boiling curve specific enthalpy of water
Information
Extends from (Return bubble point specific enthalpy).
Inputs
Outputs
| Name | Description |
|---|
| hl | Boiling curve specific enthalpy [J/kg] |
Dew curve specific enthalpy of water
Information
Extends from (Return dew point specific enthalpy).
Inputs
Outputs
| Name | Description |
|---|
| hv | Dew curve specific enthalpy [J/kg] |
Boiling curve specific entropy of water
Information
Extends from (Return bubble point specific entropy).
Inputs
Outputs
| Name | Description |
|---|
| sl | Boiling curve specific entropy [J/(kg.K)] |
Dew curve specific entropy of water
Information
Extends from (Return dew point specific entropy).
Inputs
Outputs
| Name | Description |
|---|
| sv | Dew curve specific entropy [J/(kg.K)] |
Boiling curve specific density of water
Information
Extends from (Return bubble point density).
Inputs
Outputs
| Name | Description |
|---|
| dl | Boiling curve density [kg/m3] |
Dew curve specific density of water
Information
Extends from (Return dew point density).
Inputs
Outputs
| Name | Description |
|---|
| dv | Dew curve density [kg/m3] |
Saturation temperature of water
Information
Extends from (Return saturation temperature).
Inputs
Outputs
| Name | Description |
|---|
| T | Saturation temperature [K] |
Derivative of saturation temperature w.r.t. pressure
Information
Extends from (Return derivative of saturation temperature w.r.t. pressure).
Inputs
Outputs
| Name | Description |
|---|
| dTp | Derivative of saturation temperature w.r.t. pressure [K/Pa] |
Saturation pressure of water
Information
Extends from (Return saturation pressure).
Inputs
Outputs
| Name | Description |
|---|
| p | Saturation pressure [Pa] |
Bubble point density derivative
Information
Extends from (Return bubble point density derivative).
Inputs
Outputs
| Name | Description |
|---|
| ddldp | Boiling curve density derivative [s2/m2] |
Dew point density derivative
Information
Extends from (Return dew point density derivative).
Inputs
Outputs
| Name | Description |
|---|
| ddvdp | Saturated steam density derivative [s2/m2] |
Bubble point specific enthalpy derivative
Information
Extends from (Return bubble point specific enthalpy derivative).
Inputs
Outputs
| Name | Description |
|---|
| dhldp | Boiling curve specific enthalpy derivative [J.m.s2/kg2] |
Dew point specific enthalpy derivative
Information
Extends from (Return dew point specific enthalpy derivative).
Inputs
Outputs
| Name | Description |
|---|
| dhvdp | Saturated steam specific enthalpy derivative [J.m.s2/kg2] |
Return thermodynamic state of water as function of d, T, and optional region
Information
Extends from (Return thermodynamic state as function of d, T and composition X or Xi).
Inputs
Outputs
| Name | Description |
|---|
| state | Thermodynamic state record |
Return thermodynamic state of water as function of p, h, and optional region
Information
Extends from (Return thermodynamic state as function of p, h and composition X or Xi).
Inputs
Outputs
| Name | Description |
|---|
| state | Thermodynamic state record |
Return thermodynamic state of water as function of p, s, and optional region
Information
Extends from (Return thermodynamic state as function of p, s and composition X or Xi).
Inputs
Outputs
| Name | Description |
|---|
| state | Thermodynamic state record |
Return thermodynamic state of water as function of p, T, and optional region
Information
Extends from (Return thermodynamic state as function of p, T and composition X or Xi).
Inputs
Outputs
| Name | Description |
|---|
| state | Thermodynamic state record |
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
Outputs
| Name | Description |
|---|
| state | Smooth thermodynamic state for all x (continuous and differentiable) |
Automatically generated Thu Dec 19 17:20:22 2019.
Modelica.Media.Water.WaterIF97_base.ThermodynamicState
Modelica.Media.Water.WaterIF97_base.BaseProperties
Modelica.Media.Water.WaterIF97_base.density_ph
Modelica.Media.Water.WaterIF97_base.specificEnthalpy
Modelica.Media.Water.WaterIF97_base.specificEntropy