packageConstantProperties_pT

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

Extends from Buildings.Media.Water.

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);

Parameters

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

Revisions

September 20, 2016, by Michael Wetter:
Reordered constants to conform with the order in package.order.
This is for issue 518.
September 14, 2016, by Michael Wetter:
Revised implementation.
September 8, 2016, by Marcus Fuchs:
First implementation.