## Buildings.Media.Water

Package with model for liquid water with constant density

### Information

This medium package models liquid water.

The mass density is computed using a constant value of *995.586* kg/s.
For a medium model in which the density is a function of temperature, use
Buildings.Media.Specialized.Water.TemperatureDependentDensity which may have considerably higher computing time.

For the specific heat capacities at constant pressure and at constant volume,
a constant value of *4184* J/(kg K), which corresponds to *20*°C
is used.
The figure below shows the relative error of the specific heat capacity that
is introduced by this simplification.

The enthalpy is computed using the convention that *h=0*
if *T=0* °C.

#### Limitations

Density, specific heat capacity, thermal conductivity and viscosity are constant. Water is modeled as an incompressible liquid. There are no phase changes.

Extends from Modelica.Media.Water.ConstantPropertyLiquidWater (Water: Simple liquid water medium (incompressible, constant data)), Modelica.Icons.Package (Icon for standard packages).

### Package Content

Name | Description |
---|---|

BaseProperties | Base properties |

enthalpyOfLiquid | Return the specific enthalpy of liquid |

Inherited | |

simpleWaterConstants | |

cp_const | Constant specific heat capacity at constant pressure |

cv_const | Constant specific heat capacity at constant volume |

d_const | Constant density |

eta_const | Constant dynamic viscosity |

lambda_const | Constant thermal conductivity |

a_const | Constant velocity of sound |

T_min | Minimum temperature valid for medium model |

T_max | Maximum temperature valid for medium model |

T0=reference_T | Zero enthalpy temperature |

MM_const | Molar mass |

fluidConstants | Fluid constants |

ThermodynamicState | Thermodynamic state |

setState_pTX | Return thermodynamic state from p, T, and X or Xi |

setState_phX | Return thermodynamic state from p, h, and X or Xi |

setState_psX | Return thermodynamic state from p, s, and X or Xi |

setState_dTX | Return thermodynamic state from d, T, and X or Xi |

setSmoothState | Return thermodynamic state so that it smoothly approximates: if x > 0 then state_a else state_b |

dynamicViscosity | Return dynamic viscosity |

thermalConductivity | Return thermal conductivity |

pressure | Return pressure |

temperature | Return temperature |

density | Return density |

specificEnthalpy | Return specific enthalpy |

specificHeatCapacityCp | Return specific heat capacity at constant pressure |

specificHeatCapacityCv | Return specific heat capacity at constant volume |

isentropicExponent | Return isentropic exponent |

velocityOfSound | Return velocity of sound |

specificEnthalpy_pTX | Return specific enthalpy from p, T, and X or Xi |

temperature_phX | Return temperature from p, h, and X or Xi |

density_phX | Return density from p, h, and X or Xi |

specificInternalEnergy | Return specific internal energy |

specificEntropy | Return specific entropy |

specificGibbsEnergy | Return specific Gibbs energy |

specificHelmholtzEnergy | Return specific Helmholtz energy |

isentropicEnthalpy | Return isentropic enthalpy |

isobaricExpansionCoefficient | Returns overall the isobaric expansion coefficient beta |

isothermalCompressibility | Returns overall the isothermal compressibility factor |

density_derp_T | Returns the partial derivative of density with respect to pressure at constant temperature |

density_derT_p | Returns the partial derivative of density with respect to temperature at constant pressure |

density_derX | Returns the partial derivative of density with respect to mass fractions at constant pressure and temperature |

molarMass | Return the molar mass of the medium |

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 |

density_ph | Return density from p and h |

temperature_ph | Return temperature from p and h |

pressure_dT | Return pressure from d and T |

specificEnthalpy_dT | Return specific enthalpy from d and T |

specificEnthalpy_ps | Return specific enthalpy from p and s |

temperature_ps | Return temperature from p and s |

density_ps | Return density from p and s |

specificEnthalpy_pT | Return specific enthalpy from p and T |

density_pT | Return density from p and T |

ThermoStates | Enumeration type for independent variables |

mediumName="unusablePartialMedium" | 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, 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=false | = 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) |

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_h | Return density derivative w.r.t. pressure at const specific enthalpy |

density_derh_p | Return density derivative w.r.t. specific enthalpy at constant pressure |

specificEntropy_pTX | Return specific enthalpy from p, T, and X or Xi |

density_pTX | Return density from p, T, 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 |

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 |

## Buildings.Media.Water.BaseProperties

Base properties

### Information

This base properties model is identical to
Modelica.Media.Water.ConstantPropertyLiquidWater,
except that the equation
`u = cv_const*(T - reference_T)`

has been replaced by `u=h`

because
`cp_const=cv_const`

.

### Parameters

Type | Name | Default | Description |
---|---|---|---|

Advanced | |||

Boolean | preferredMediumStates | false | = true if StateSelect.prefer shall be used for the independent property variables of the medium |

### Modelica definition

## Buildings.Media.Water.enthalpyOfLiquid

Return the specific enthalpy of liquid

### Information

Enthalpy of the water.

Extends from Modelica.Icons.Function (Icon for functions).

### Inputs

Type | Name | Default | Description |
---|---|---|---|

Temperature | T | Temperature [K] |

### Outputs

Type | Name | Description |
---|---|---|

SpecificEnthalpy | h | Specific enthalpy [J/kg] |

### Modelica definition

## Buildings.Media.Water.BaseProperties.InputAbsolutePressure

Pressure as input signal connector

### Modelica definition

## Buildings.Media.Water.BaseProperties.InputMassFraction

Mass fraction as input signal connector

### Modelica definition

## Buildings.Media.Water.BaseProperties.InputSpecificEnthalpy

Specific enthalpy as input signal connector