Water: Steam properties as defined by IAPWS/IF97 standard
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:
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).
Name | Description |
---|---|
SaturationProperties | |
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 pressure |
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.Units.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 |
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 |
Extends from (Saturation properties of two phase medium).
Thermodynamic state
Extends from (Thermodynamic state of two phase medium).
Base properties of water
Extends from (Base properties (p, d, T, h, u, R_s, MM, sat) of two phase medium).
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
Extends from Modelica.Icons.Function (Icon for functions).
Name | Description |
---|---|
p | Pressure [Pa] |
h | Specific enthalpy [J/kg] |
phase | 2 for two-phase, 1 for one-phase, 0 if not known |
region | If 0, region is unknown, otherwise known and this input |
Name | Description |
---|---|
d | Density [kg/m3] |
Computes temperature as a function of pressure and specific enthalpy
Extends from Modelica.Icons.Function (Icon for functions).
Name | Description |
---|---|
p | Pressure [Pa] |
h | Specific enthalpy [J/kg] |
phase | 2 for two-phase, 1 for one-phase, 0 if not known |
region | If 0, region is unknown, otherwise known and this input |
Name | Description |
---|---|
T | Temperature [K] |
Compute temperature from pressure and specific enthalpy
Extends from Modelica.Icons.Function (Icon for functions).
Name | Description |
---|---|
p | Pressure [Pa] |
s | Specific entropy [J/(kg.K)] |
phase | 2 for two-phase, 1 for one-phase, 0 if not known |
region | If 0, region is unknown, otherwise known and this input |
Name | Description |
---|---|
T | Temperature [K] |
Computes density as a function of pressure and specific enthalpy
Extends from Modelica.Icons.Function (Icon for functions).
Name | Description |
---|---|
p | Pressure [Pa] |
s | Specific entropy [J/(kg.K)] |
phase | 2 for two-phase, 1 for one-phase, 0 if not known |
region | If 0, region is unknown, otherwise known and this input |
Name | Description |
---|---|
d | Density [kg/m3] |
Computes pressure as a function of density and temperature
Extends from Modelica.Icons.Function (Icon for functions).
Name | Description |
---|---|
d | Density [kg/m3] |
T | Temperature [K] |
phase | 2 for two-phase, 1 for one-phase, 0 if not known |
region | If 0, region is unknown, otherwise known and this input |
Name | Description |
---|---|
p | Pressure [Pa] |
Computes specific enthalpy as a function of density and temperature
Extends from Modelica.Icons.Function (Icon for functions).
Name | Description |
---|---|
d | Density [kg/m3] |
T | Temperature [K] |
phase | 2 for two-phase, 1 for one-phase, 0 if not known |
region | If 0, region is unknown, otherwise known and this input |
Name | Description |
---|---|
h | Specific enthalpy [J/kg] |
Computes specific enthalpy as a function of pressure and temperature
Extends from Modelica.Icons.Function (Icon for functions).
Name | Description |
---|---|
p | Pressure [Pa] |
T | Temperature [K] |
phase | 2 for two-phase, 1 for one-phase, 0 if not known |
region | If 0, region is unknown, otherwise known and this input |
Name | Description |
---|---|
h | Specific enthalpy [J/kg] |
Computes specific enthalpy as a function of pressure and temperature
Extends from Modelica.Icons.Function (Icon for functions).
Name | Description |
---|---|
p | Pressure [Pa] |
s | Specific entropy [J/(kg.K)] |
phase | 2 for two-phase, 1 for one-phase, 0 if not known |
region | If 0, region is unknown, otherwise known and this input |
Name | Description |
---|---|
h | Specific enthalpy [J/kg] |
Computes density as a function of pressure and temperature
Extends from Modelica.Icons.Function (Icon for functions).
Name | Description |
---|---|
p | Pressure [Pa] |
T | Temperature [K] |
phase | 2 for two-phase, 1 for one-phase, 0 if not known |
region | If 0, region is unknown, otherwise known and this input |
Name | Description |
---|---|
d | Density [kg/m3] |
Set the thermodynamic state on the dew line
Extends from (Return the thermodynamic state on the dew line).
Name | Description |
---|---|
sat | Saturation point |
phase | Phase: default is one phase |
Name | Description |
---|---|
state | Complete thermodynamic state info |
Set the thermodynamic state on the bubble line
Extends from (Return the thermodynamic state on the bubble line).
Name | Description |
---|---|
sat | Saturation point |
phase | Phase: default is one phase |
Name | Description |
---|---|
state | Complete thermodynamic state info |
Dynamic viscosity of water
Extends from (Return dynamic viscosity).
Name | Description |
---|---|
state | Thermodynamic state record |
Name | Description |
---|---|
eta | Dynamic viscosity [Pa.s] |
Thermal conductivity of water
Extends from (Return thermal conductivity).
Name | Description |
---|---|
state | Thermodynamic state record |
Name | Description |
---|---|
lambda | Thermal conductivity [W/(m.K)] |
Surface tension in two phase region of water
Extends from (Return surface tension sigma in the two phase region).
Name | Description |
---|---|
sat | Saturation property record |
Name | Description |
---|---|
sigma | Surface tension sigma in the two phase region [N/m] |
Return pressure of ideal gas
Extends from (Return pressure).
Name | Description |
---|---|
state | Thermodynamic state record |
Name | Description |
---|---|
p | Pressure [Pa] |
Return temperature of ideal gas
Extends from (Return temperature).
Name | Description |
---|---|
state | Thermodynamic state record |
Name | Description |
---|---|
T | Temperature [K] |
Return density of ideal gas
Extends from (Return density).
Name | Description |
---|---|
state | Thermodynamic state record |
Name | Description |
---|---|
d | Density [kg/m3] |
Return specific enthalpy
Extends from Modelica.Icons.Function (Icon for functions), (Return specific enthalpy).
Name | Description |
---|---|
state | Thermodynamic state record |
Name | Description |
---|---|
h | Specific enthalpy [J/kg] |
Return specific internal energy
Extends from Modelica.Icons.Function (Icon for functions), (Return specific internal energy).
Name | Description |
---|---|
state | Thermodynamic state record |
Name | Description |
---|---|
u | Specific internal energy [J/kg] |
Return specific Gibbs energy
Extends from Modelica.Icons.Function (Icon for functions), (Return specific Gibbs energy).
Name | Description |
---|---|
state | Thermodynamic state record |
Name | Description |
---|---|
g | Specific Gibbs energy [J/kg] |
Return specific Helmholtz energy
Extends from Modelica.Icons.Function (Icon for functions), (Return specific Helmholtz energy).
Name | Description |
---|---|
state | Thermodynamic state record |
Name | Description |
---|---|
f | Specific Helmholtz energy [J/kg] |
Specific entropy of water
Extends from (Return specific entropy).
Name | Description |
---|---|
state | Thermodynamic state record |
Name | Description |
---|---|
s | Specific entropy [J/(kg.K)] |
Specific heat capacity at constant pressure of water
Extends from (Return specific heat capacity at constant pressure).
Name | Description |
---|---|
state | Thermodynamic state record |
Name | Description |
---|---|
cp | Specific heat capacity at constant pressure [J/(kg.K)] |
Specific heat capacity at constant volume of water
Extends from (Return specific heat capacity at constant volume).
Name | Description |
---|---|
state | Thermodynamic state record |
Name | Description |
---|---|
cv | Specific heat capacity at constant volume [J/(kg.K)] |
Return isentropic exponent
Extends from (Return isentropic exponent).
Name | Description |
---|---|
state | Thermodynamic state record |
Name | Description |
---|---|
gamma | Isentropic exponent [1] |
Isothermal compressibility of water
Extends from (Return overall the isothermal compressibility factor).
Name | Description |
---|---|
state | Thermodynamic state record |
Name | Description |
---|---|
kappa | Isothermal compressibility [1/Pa] |
Isobaric expansion coefficient of water
Extends from (Return overall the isobaric expansion coefficient beta).
Name | Description |
---|---|
state | Thermodynamic state record |
Name | Description |
---|---|
beta | Isobaric expansion coefficient [1/K] |
Return velocity of sound as a function of the thermodynamic state record
Extends from (Return velocity of sound).
Name | Description |
---|---|
state | Thermodynamic state record |
Name | Description |
---|---|
a | Velocity of sound [m/s] |
Compute h(s,p)
Extends from (Return isentropic enthalpy).
Name | Description |
---|---|
p_downstream | Downstream pressure [Pa] |
refState | Reference state for entropy |
Name | Description |
---|---|
h_is | Isentropic enthalpy [J/kg] |
Density derivative by specific enthalpy
Extends from (Return density derivative w.r.t. specific enthalpy at constant pressure).
Name | Description |
---|---|
state | Thermodynamic state record |
Name | Description |
---|---|
ddhp | Density derivative w.r.t. specific enthalpy [kg.s2/m5] |
Density derivative by pressure
Extends from (Return density derivative w.r.t. pressure at const specific enthalpy).
Name | Description |
---|---|
state | Thermodynamic state record |
Name | Description |
---|---|
ddph | Density derivative w.r.t. pressure [s2/m2] |
Boiling curve specific enthalpy of water
Extends from (Return bubble point specific enthalpy).
Name | Description |
---|---|
sat | Saturation property record |
Name | Description |
---|---|
hl | Boiling curve specific enthalpy [J/kg] |
Dew curve specific enthalpy of water
Extends from (Return dew point specific enthalpy).
Name | Description |
---|---|
sat | Saturation property record |
Name | Description |
---|---|
hv | Dew curve specific enthalpy [J/kg] |
Boiling curve specific entropy of water
Extends from (Return bubble point specific entropy).
Name | Description |
---|---|
sat | Saturation property record |
Name | Description |
---|---|
sl | Boiling curve specific entropy [J/(kg.K)] |
Dew curve specific entropy of water
Extends from (Return dew point specific entropy).
Name | Description |
---|---|
sat | Saturation property record |
Name | Description |
---|---|
sv | Dew curve specific entropy [J/(kg.K)] |
Boiling curve specific density of water
Extends from (Return bubble point density).
Name | Description |
---|---|
sat | Saturation property record |
Name | Description |
---|---|
dl | Boiling curve density [kg/m3] |
Dew curve specific density of water
Extends from (Return dew point density).
Name | Description |
---|---|
sat | Saturation property record |
Name | Description |
---|---|
dv | Dew curve density [kg/m3] |
Saturation temperature of water
Extends from (Return saturation temperature).
Name | Description |
---|---|
p | Pressure [Pa] |
Name | Description |
---|---|
T | Saturation temperature [K] |
Derivative of saturation temperature w.r.t. pressure
Extends from (Return derivative of saturation temperature w.r.t. pressure).
Name | Description |
---|---|
p | Pressure [Pa] |
Name | Description |
---|---|
dTp | Derivative of saturation temperature w.r.t. pressure [K/Pa] |
Saturation pressure of water
Extends from (Return saturation pressure).
Name | Description |
---|---|
T | Temperature [K] |
Name | Description |
---|---|
p | Saturation pressure [Pa] |
Bubble point density derivative
Extends from (Return bubble point density derivative).
Name | Description |
---|---|
sat | Saturation property record |
Name | Description |
---|---|
ddldp | Boiling curve density derivative [s2/m2] |
Dew point density derivative
Extends from (Return dew point density derivative).
Name | Description |
---|---|
sat | Saturation property record |
Name | Description |
---|---|
ddvdp | Saturated steam density derivative [s2/m2] |
Bubble point specific enthalpy derivative
Extends from (Return bubble point specific enthalpy derivative).
Name | Description |
---|---|
sat | Saturation property record |
Name | Description |
---|---|
dhldp | Boiling curve specific enthalpy derivative [J.m.s2/kg2] |
Dew point specific enthalpy derivative
Extends from (Return dew point specific enthalpy derivative).
Name | Description |
---|---|
sat | Saturation property record |
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
Extends from (Return thermodynamic state as function of d, T and composition X or Xi).
Name | Description |
---|---|
d | Density [kg/m3] |
T | Temperature [K] |
X[:] | Mass fractions [kg/kg] |
phase | 2 for two-phase, 1 for one-phase, 0 if not known |
region | If 0, region is unknown, otherwise known and this input |
Name | Description |
---|---|
state | Thermodynamic state record |
Return thermodynamic state of water as function of p, h, and optional region
Extends from (Return thermodynamic state as function of p, h and composition X or Xi).
Name | Description |
---|---|
p | Pressure [Pa] |
h | Specific enthalpy [J/kg] |
X[:] | Mass fractions [kg/kg] |
phase | 2 for two-phase, 1 for one-phase, 0 if not known |
region | If 0, region is unknown, otherwise known and this input |
Name | Description |
---|---|
state | Thermodynamic state record |
Return thermodynamic state of water as function of p, s, and optional region
Extends from (Return thermodynamic state as function of p, s and composition X or Xi).
Name | Description |
---|---|
p | Pressure [Pa] |
s | Specific entropy [J/(kg.K)] |
X[:] | Mass fractions [kg/kg] |
phase | 2 for two-phase, 1 for one-phase, 0 if not known |
region | If 0, region is unknown, otherwise known and this input |
Name | Description |
---|---|
state | Thermodynamic state record |
Return thermodynamic state of water as function of p, T, and optional region
Extends from (Return thermodynamic state as function of p, T and composition X or Xi).
Name | Description |
---|---|
p | Pressure [Pa] |
T | Temperature [K] |
X[:] | Mass fractions [kg/kg] |
phase | 2 for two-phase, 1 for one-phase, 0 if not known |
region | If 0, region is unknown, otherwise known and this input |
Name | Description |
---|---|
state | Thermodynamic state record |
Return thermodynamic state so that it smoothly approximates: if x > 0 then state_a else state_b
Extends from (Return thermodynamic state so that it smoothly approximates: if x > 0 then state_a else state_b).
Name | Description |
---|---|
x | m_flow or dp |
state_a | Thermodynamic state if x > 0 |
state_b | Thermodynamic state if x < 0 |
x_small | Smooth transition in the region -x_small < x < x_small |
Name | Description |
---|---|
state | Smooth thermodynamic state for all x (continuous and differentiable) |