modelBaseProperties
Extends from BasePropertiesRecord (Variables contained in every instance of BaseProperties).
Information
Model BaseProperties is a model within package PartialMedium and contains the declarations of the minimum number of variables that every medium model is supposed to support. A specific medium inherits from model BaseProperties and provides the equations for the basic properties. Note, that in package PartialMedium the following constants are defined:
| Type | Name | Description |
| String | mediumName | Unique name of the medium (used to check whether two media in a model are the same) |
| String | substanceNames | Names of the mixture substances that are treated as independent. If medium consists of a single substance, set substanceNames=fill("",0). If medium consists of n substances, provide either n-1 or n substance names, depending whether mass fractions PartialMedium.BaseProperties.X shall have dimension PartialMedium.nX = n-1 or PartialMedium.nX = n |
| Boolean | incompressible | = true, if density is constant; otherwise set it to false |
In every medium 3+nX equations have to be defined that provide relations between the following 5+nX variables, declared in model BaseProperties, where nX is the number of independent mass fractions defined in package PartialMedium:
| Variable | Unit | Description |
| T | K | temperature |
| p | Pa | absolute pressure |
| d | kg/m^3 | density |
| h | J/kg | specific enthalpy |
| u | J/kg | specific internal energy |
| X[nX] | kg/kg | independent mass fractions m_i/m |
In some components, such as "Ambient", explicit equations for medium variables are provided as "boundary conditions". For example, the "Ambient" component may define a temperature T_ambient.
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| Boolean | standardOrderComponents | true | if true, last element in components is computed from 1-sum(Xi) |
| Advanced | |||
| Boolean | preferredMediumStates | false | = true if StateSelect.prefer shall be used for the independent property variables of the medium |
Components
| Type | Name | Default | Description |
|---|---|---|---|
| AbsolutePressure | p (from BasePropertiesRecord) | Absolute pressure of medium | |
| Density | d (from BasePropertiesRecord) | Density of medium | |
| Temperature | T (from BasePropertiesRecord) | Temperature of medium | |
| MassFraction | X (from BasePropertiesRecord) | Mass fractions (= (component mass)/total mass m_i/m) | |
| MassFraction | Xi (from BasePropertiesRecord) | Structurally independent mass fractions | |
| SpecificHeatCapacity | R (from BasePropertiesRecord) | Gas constant (of mixture if applicable) | |
| MolarMass | MM (from BasePropertiesRecord) | Molar mass (of mixture or single fluid) | |
| ThermodynamicState | state | thermodynamic state variables for optional functions | |
| Modelica.Units.NonSI.Temperature_degC | T_degC | Modelica.Units.Conversions.to_degC(T) | Temperature of medium in [degC] |
| Modelica.Units.NonSI.Pressure_bar | p_bar | Modelica.Units.Conversions.to_bar(p) | Absolute pressure of medium in [bar] |