packageR290_IIR_P05_30_T263_343_Formula
Extends from AixLib.Media.Refrigerants.Interfaces.PartialHybridTwoPhaseMediumFormula (Base class for two phase medium using a hybrid approach without records).
Information
This package provides a refrigerant model for R290 using a hybrid approach developed by Sangi et al.. The hybrid approach is implemented in AixLib.Media.Refrigerants.Interfaces.PartialHybridTwoPhaseMediumRecord and the refrigerant model is implemented by complete the template AixLib.Media.Refrigerants.Interfaces.TemplateHybridTwoPhaseMediumRecord .
Assumptions and limitations
The implemented coefficients are fitted to external data by Sangi et
al. and are valid within the following range:
|
Parameter |
Minimum Value |
Maximum Value |
|
Pressure (p) in bar |
0.5 |
30 |
|
Temperature (T) in K |
263.15 |
343.15 |
Validation
Sangi et al. validated their model by comparing it to results obtained from the Helmholtz equation of state. They found out that relative error of the refrigerant model compared to HelmholtzMedia (Thorade and Saadat, 2012) is close to zero.
References
Thorade, Matthis; Saadat, Ali (2012): HelmholtzMedia - A fluid properties library. In: Proceedings of the 9th International Modelica Conference; September 3-5; 2012; Munich; Germany. Linköping University Electronic Press, S. 63–70.
Sangi, Roozbeh; Jahangiri, Pooyan; Klasing, Freerk; Streblow, Rita; Müller, Dirk (2014): A Medium Model for the Refrigerant Propane for Fast and Accurate Dynamic Simulations. In: The 10th International Modelica Conference. Lund, Sweden, March 10-12, 2014: Linköping University Electronic Press (Linköping Electronic Conference Proceedings), S. 1271–1275
Klasing,Freerk: A New Design for Direct Exchange Geothermal Heat Pumps - Modeling, Simulation and Exergy Analysis. Master thesis
Scalabrin, G.; Marchi, P.; Span, R. (2006): A Reference Multiparameter Viscosity Equation for Propane with an Optimized Functional Form. In: J. Phys. Chem. Ref. Data, Vol. 35, No. 3, S. 1415-1442
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| Modelica.Media.Interfaces.PartialTwoPhaseMedium.FluidConstants | refrigerantConstants | Thermodynamic constants for Propane | |
| Modelica.Media.Interfaces.Choices.IndependentVariables | ThermoStates (from PartialMedium) | Enumeration type for independent variables | |
| String | mediumName (from PartialMedium) | "unusablePartialMedium" | Name of the medium |
| String[:] | substanceNames (from PartialMedium) | {mediumName} | Names of the mixture substances. Set substanceNames={mediumName} if only one substance. |
| String[:] | extraPropertiesNames (from PartialMedium) | fill("", 0) | Names of the additional (extra) transported properties. Set extraPropertiesNames=fill("",0) if unused |
| Boolean | singleState (from PartialMedium) | = true, if u and d are not a function of pressure | |
| Boolean | reducedX (from PartialMedium) | true | = true, if medium contains the equation sum(X) = 1.0; set reducedX=true, if only one substance (see docu for details) |
| Boolean | fixedX (from PartialMedium) | false | = true, if medium contains the equation X = reference_X |
| AbsolutePressure | reference_p (from PartialMedium) | 101325 | Reference pressure of Medium: default 1 atmosphere |
| Temperature | reference_T (from PartialMedium) | 298.15 | Reference temperature of Medium: default 25 deg Celsius |
| MassFraction[nX] | reference_X (from PartialMedium) | fill(1/nX, nX) | Default mass fractions of medium |
| AbsolutePressure | p_default (from PartialMedium) | 101325 | Default value for pressure of medium (for initialization) |
| Temperature | T_default (from PartialMedium) | Modelica.Units.Conversions.from_degC(20) | Default value for temperature of medium (for initialization) |
| SpecificEnthalpy | h_default (from PartialMedium) | specificEnthalpy_pTX(p_default, T_default, X_default) | Default value for specific enthalpy of medium (for initialization) |
| MassFraction[nX] | X_default (from PartialMedium) | reference_X | Default value for mass fractions of medium (for initialization) |
| ExtraProperty[nC] | C_default (from PartialMedium) | fill(0, nC) | Default value for trace substances of medium (for initialization) |
| Integer | nS (from PartialMedium) | size(substanceNames, 1) | Number of substances |
| Integer | nX (from PartialMedium) | nS | Number of mass fractions |
| Integer | nXi (from PartialMedium) | if fixedX then 0 else if reducedX then nS - 1 else nS | Number of structurally independent mass fractions (see docu for details) |
| Integer | nC (from PartialMedium) | size(extraPropertiesNames, 1) | Number of extra (outside of standard mass-balance) transported properties |
| Real[nC] | C_nominal (from PartialMedium) | 1.0e-6*ones(nC) | Default for the nominal values for the extra properties |
| Boolean | smoothModel (from PartialTwoPhaseMedium) | false | = true, if the (derived) model should not generate state events |
| Boolean | onePhase (from PartialTwoPhaseMedium) | false | = true, if the (derived) model should never be called with two-phase inputs |
| FluidConstants | fluidConstants (from PartialTwoPhaseMedium) | Constant data for the fluid |
Contents
| Name | Description |
|---|---|
| SmoothTransition | Record that contains ranges to calculate a smooth transition between different regions |
| f_Idg | Dimensionless Helmholtz energy (Ideal gas contribution alpha_0) |
| f_Res | Dimensionless Helmholtz energy (Residual part alpha_r) |
| t_fIdg_t | Short form for tau*(dalpha_0/dtau)_delta=const |
| tt_fIdg_tt | Short form for tau*tau*(ddalpha_0/(dtau*dtau))_delta=const |
| t_fRes_t | Short form for tau*(dalpha_r/dtau)_delta=const |
| tt_fRes_tt | Short form for tau*tau*(ddalpha_r/(dtau*dtau))_delta=const |
| d_fRes_d | Short form for delta*(dalpha_r/(ddelta))_tau=const |
| dd_fRes_dd | Short form for delta*delta(ddalpha_r/(ddelta*delta))_tau=const |
| td_fRes_td | Short form for tau*delta*(ddalpha_r/(dtau*ddelta)) |
| ttt_fIdg_ttt | Short form for tau*tau*tau*(dddalpha_0/(dtau*dtau*dtau))_delta=const |
| ttt_fRes_ttt | Short form for tau*tau*tau*(dddalpha_r/(dtau*dtau*dtau))_delta=const |
| ddd_fRes_ddd | Short form for delta*delta*delta* (dddalpha_r/(ddelta*ddelta*ddelta))_tau=const |
| tdd_fRes_tdd | Short form for tau*delta*delta*(dddalpha_r/(dtau*ddelta*ddelta)) |
| ttd_fRes_ttd | Short form for tau*tau*delta*(dddalpha_r/(dtau*dtau*ddelta)) |
 saturationPressure | Saturation pressure of refrigerant (Ancillary equation) |
 saturationTemperature | Saturation temperature of refrigerant (Ancillary equation) |
 bubbleDensity | Boiling curve specific density of refrigerant (Ancillary equation) |
 dewDensity | Dew curve specific density of refrigerant (Ancillary equation) |
 bubbleEnthalpy | Boiling curve specific enthalpy of refrigerant (Ancillary equation) |
 dewEnthalpy | Dew curve specific enthalpy of refrigerant (Ancillary equation) |
 bubbleEntropy | Boiling curve specific entropy of refrigerant (Ancillary equation) |
 dewEntropy | Dew curve specific entropy of propane (Ancillary equation) |
 temperature_ph | Calculates temperature as function of pressure and specific enthalpy |
 temperature_ps | Calculates temperature as function of pressure and specific entroy |
 density_pT | Computes density as a function of pressure and temperature |
 dynamicViscosity | Calculates dynamic viscosity of refrigerant |
 thermalConductivity | Calculates thermal conductivity of refrigerant |
 surfaceTension | Surface tension in two phase region of refrigerant |
Revisions
- June 12, 2017, by Mirko Engelpracht, Christian Vering:
First implementation (see issue 408).