modelRefrigerantsFittedFormulasR134a
Model that checks the fitted formulas of R134a
Extends from Modelica.Icons.Example (Icon for runnable examples).
Information
This example models checks the implementation of the refrigerant's fitted formulas depending on the independent variables density and temperature. Therefore, the user has first to introduce some information about the refrigerant and afterwards the fitted formulas are calculated. The following refrigerant's information is required:
- The refrigerant package that shall be tested.
- The refrigerant's fluid limits that are determined by the fitting procedure.
The following refrigerant's fitted formulas are calculated and checked:
- Calculation of the Helmholtz equation of state.
- Calculation of the saturation properties.
- Calculation of further state propeties like the density depending on pressure and temperature.
Additionally, the fitted formulas are also calculated with an external media libary (i.e. HelmholtzMedia). Therefore, the parameters are not allowed to change (except for the medium package).
- August 13, 2017, by Mirko Engelpracht:
First implementation (see issue 408).
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| Fluid limits | |||
| Modelica.Units.SI.SpecificEnthalpy | h_min | 180e3 | Fluid limit: Minimum specific enthalpy |
| Modelica.Units.SI.SpecificEnthalpy | h_max | 550e3 | Fluid limit: Maximum specific enthalpy |
| Modelica.Units.SI.SpecificEntropy | s_min | 1.0e3 | Fluid limit: Minimum specific entropy |
| Modelica.Units.SI.SpecificEntropy | s_max | 1.8e3 | Fluid limit: Maximum specific entropy |
| Modelica.Units.SI.Density | d_min | 2.0 | Fluid limit: Minimum density |
| Modelica.Units.SI.Density | d_max | 1425 | Fluid limit: Maximum density |
| Modelica.Units.SI.AbsolutePressure | p_min | 1e5 | Fluid limit: Minimum absolute pressure |
| Modelica.Units.SI.AbsolutePressure | p_max | 38.5e5 | Fluid limit: Maximum absolute pressure |
| Modelica.Units.SI.Temperature | T_min | 233.15 | Fluid limit: Minimum temperature |
| Modelica.Units.SI.Temperature | T_max | 455.15 | Fluid limit: Maximum temperature |
Components
| Type | Name | Default | Description |
|---|---|---|---|
| Modelica.Blocks.Sources.CombiTimeTable | extProp | Table that contains the results of the external media library | |
| Real | convT | Conversion factor in K/s for temperature to satisfy unit check | |
| Real | convD | Conversion factor in kg/m³/s for density to satisfy unit check | |
| Real | convH | Conversion factor in J/kg/s for specific enthalpy to satisfy unit check | |
| Real | convS | Conversion factor in J/kg/K/s for specific entropy to satisfy unit check | |
| Modelica.Units.SI.AbsolutePressure | p_sat | Actual pressure for calculating saturation properties | |
| Modelica.Units.SI.Temperature | T | Actual pulsating temperature | |
| Modelica.Units.SI.Temperature | T_sat | Actual temperature for calculating saturation properties | |
| Modelica.Units.SI.Density | d | Actual raising density | |
| Modelica.Units.SI.SpecificEnthalpy | h | Actual pulsating specific enthalpy for calculating state properties | |
| Modelica.Units.SI.SpecificEntropy | s | Actual pulsating specific enthalpy for calculating state properties | |
| Real | tauInt | Actual dimensionless temperature of internal medium | |
| Real | deltaInt | Actual dimensionless density of internal medium | |
| EoS | eos | Record that contains calculated properties of the EoS | |
| Saturation | saturation | Record that contains calculated saturation properties | |
| Properties | properties | Record that contains calculated state properties |
Contents
| Name | Description |
|---|---|
 MediumInt | Internal medium model |
| EoS | Record that contains calculated properties of the EoS |
| Saturation | Record that contains calculated saturation properties |
| Properties | Record that contains state properties |