modelRefrigerantsDerivativesR290
Model that checks the implementation of derivatives for R134a
Extends from RefrigerantsDerivativesR134a (Model that checks the implementation of derivatives for R134a).
Information
This example model checks the implementation of the refrigerant's partial derivatives. Therefore, the user has first to introduce some information about the refrigerant and afterwards the partial derivatives are calculated. The following refrigerant's information is required:
- The refrigerant package that shall be tested.
- The independent variables i.e. independents variables' alteration with time.
The following refrigerant's partial derivatives are calculated and checked:
- Thermodynamic properties calculated by partial derivatives of the Helmholtz equation of state (e.g. specific heat capacity at constant pressure).
- Partial derivatives that only depend on partial derivatives of the Helmholtz equation of state (i.e. derivatives wrt. density and temperature).
- Partial derivatives that do not directly depend on partial derivatives of the Helmholtz equation of state (i.e. derivatives not wrt. density and temperature).
- Partial derivatives at bubble and dew line.
Furthermore, the derivatives are compared with the associated derivatives calculated by an external medium model (i.e. HelmholtzMedia) Therefore, the parameters are not allowed to change (except for the medium package).
- August 13, 2017, by Mirko Engelpracht, Christian Vering:
First implementation (see issue 408).
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| MediumInt.AbsolutePressure | p0 (from RefrigerantsDerivativesR134a) | 20e5 | Fixed pressure for calculations at initialization |
| MediumInt.Density | d0 (from RefrigerantsDerivativesR134a) | 75 | Fixed density for calculations at initialization |
| Real | convT (from RefrigerantsDerivativesR134a) | 125 | Conversion factor to satisfy derivative check |
| Real | convH (from RefrigerantsDerivativesR134a) | 300e3 | Conversion factor to satisfy derivative check |
| Real | convS (from RefrigerantsDerivativesR134a) | 750 | Conversion factor to satisfy derivative check |
Components
| Type | Name | Default | Description |
|---|---|---|---|
| MediumInt.AbsolutePressure | p (from RefrigerantsDerivativesR134a) | p0 + 10e5*time^3 | Pressure used for calculations |
| MediumInt.Temperature | T (from RefrigerantsDerivativesR134a) | 273.15 + convT*time^3 | Temperature used for calculations |
| MediumInt.Density | d (from RefrigerantsDerivativesR134a) | d0 + 125*time^3 | Density used for calculations |
| MediumInt.SpecificEnthalpy | h (from RefrigerantsDerivativesR134a) | 200e3 + convH*time^3 | Specific enthalpy used for calculations |
| MediumInt.SpecificEntropy | s (from RefrigerantsDerivativesR134a) | 1e3 + convS*time^3 | Specific entropy used for calculations |
| Modelica.Blocks.Sources.CombiTimeTable | extProp (from RefrigerantsDerivativesR134a) | Table that contains the results of the external media library | |
| States | states (from RefrigerantsDerivativesR134a) | Record that contains thermodynamic states calculated by independent state variables | |
| DerProp | derProp (from RefrigerantsDerivativesR134a) | Record that contains thermodynamic properties derived by partial derivatives | |
| ExplDer | explDer (from RefrigerantsDerivativesR134a) | Record that contains partial derivatives wrt. density and temperature | |
| FurDer | furDer (from RefrigerantsDerivativesR134a) | Record that contains further derivatives not wrt. density and temperature | |
| SatDer | satDer (from RefrigerantsDerivativesR134a) | Record that contains derivates at bubble and dew state |