Description: "Collection of models that illustrate model use and test models"

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## Buildings.Obsolete.Media.PerfectGases.Examples

Collection of models that illustrate model use and test models

### Information

This package contains examples for the use of models that can be found in Buildings.Obsolete.Media.PerfectGases.

Extends from Modelica.Icons.ExamplesPackage (Icon for packages containing runnable examples).

### Package Content

Name | Description
--- | ---
MoistAirComparison |
MoistAirDerivativeCheck |
MoistAirTemperatureEnthalpyInversion | Model to check computation of h(T) and its inverse
TestMoistAir |

## Buildings.Obsolete.Media.PerfectGases.Examples.MoistAirComparison

### Information

This example compares the perfect medium model Buildings.Obsolete.Media.PerfectGases.MoistAir with the ideal gas model from Modelica.Media.Air.MoistAir

Extends from Modelica.Icons.Example (Icon for runnable examples).

### Parameters

Type | Name | Default | Description
--- | --- | --- | ---
Pressure | P | 101325 | Pressure [Pa]

### Modelica definition

model MoistAirComparison extends Modelica.Icons.Example; package PerfectMedium = Buildings.Obsolete.Media.PerfectGases.MoistAir; //package IdealMedium = Modelica.Media.Air.MoistAir; package IdealMedium = Buildings.Obsolete.Media.GasesConstantDensity.MoistAir; Modelica.SIunits.SpecificEnthalpy hLiqPer "Liquid phase enthalpy"; Modelica.SIunits.SpecificEnthalpy hLiqIde "Liquid phase enthalpy"; Modelica.SIunits.SpecificEnthalpy hStePer "Water vapor enthalpy"; Modelica.SIunits.SpecificEnthalpy hSteIde "Water vapor enthalpy"; Modelica.SIunits.SpecificEnthalpy hAirPer "Air enthalpy"; Modelica.SIunits.SpecificEnthalpy hAirIde "Air enthalpy"; Modelica.SIunits.SpecificEnthalpy hMixPer "Mixture specific enthalpy"; Modelica.SIunits.SpecificEnthalpy hMixIde "Mixture specific enthalpy"; Modelica.SIunits.MassFraction X[2] = {0.01, 0.09}; Modelica.SIunits.Temperature T "Temperature"; Modelica.SIunits.Conversions.NonSIunits.Temperature_degC T_degC "Temperature"; Real errLiq "Error liquid phase"; Real errSte "Error steam phase"; Real errAir "Error gas mixture"; Real errMix "Error gas mixture"; Real errT "Error in temperature when enthalpy-temperature relation is inverted"; parameter Modelica.SIunits.Pressure P = 101325 "Pressure"; equation T_degC = 1+99*time; // exclude 0, to avoid large relative error T = 273.15 + T_degC; hLiqPer=PerfectMedium.enthalpyOfLiquid(T); hStePer=PerfectMedium.enthalpyOfCondensingGas(T); hAirPer=PerfectMedium.enthalpyOfGas(T, X); hLiqIde=IdealMedium.enthalpyOfLiquid(T); hSteIde=IdealMedium.enthalpyOfCondensingGas(T); hAirIde=IdealMedium.enthalpyOfGas(T, X); hMixPer=PerfectMedium.h_pTX(P, T, X); hMixIde=IdealMedium.h_pTX(P, T, X); errLiq * abs(hLiqIde+1E-3) = hLiqIde - hLiqPer; errSte * abs(hSteIde+1E-3) = hSteIde - hStePer; errAir * abs(hAirIde+1E-3) = hAirIde - hAirPer; errMix * abs(hMixIde+1E-3) = hMixIde - hMixPer; errT * T = T - PerfectMedium.T_phX(P, PerfectMedium.h_pTX(P, T, X), X); assert( abs(errLiq) < 0.09, "Error too large. Check medium model."); assert( abs(errSte) < 0.01, "Error too large. Check medium model."); assert( abs(errAir) < 0.01, "Error too large. Check medium model."); assert( abs(errMix) < 2.01, "Error too large. Check medium model."); assert( abs(errT) < 0.01, "Error too large. Check medium model."); end MoistAirComparison;

## Buildings.Obsolete.Media.PerfectGases.Examples.MoistAirDerivativeCheck

### Information

This example checks whether the function derivative is implemented correctly. If the derivative implementation is not correct, the model will stop with an assert statement.

Extends from Modelica.Icons.Example (Icon for runnable examples).

### Modelica definition

model MoistAirDerivativeCheck extends Modelica.Icons.Example; package Medium = Buildings.Obsolete.Media.PerfectGases.MoistAir; Modelica.SIunits.SpecificEnthalpy hLiqSym "Liquid phase enthalpy"; Modelica.SIunits.SpecificEnthalpy hLiqCod "Liquid phase enthalpy"; Modelica.SIunits.SpecificEnthalpy hSteSym "Water vapor enthalpy"; Modelica.SIunits.SpecificEnthalpy hSteCod "Water vapor enthalpy"; Modelica.SIunits.SpecificEnthalpy hAirSym "Dry air enthalpy"; Modelica.SIunits.SpecificEnthalpy hAirCod "Dry air enthalpy"; constant Real conv(unit="K/s") = 1 "Conversion factor to satisfy unit check"; initial equation hLiqSym = hLiqCod; hSteSym = hSteCod; hAirSym = hAirCod; equation hLiqCod=Medium.enthalpyOfLiquid(conv*time); der(hLiqCod)=der(hLiqSym); assert(abs(hLiqCod-hLiqSym) < 1E-2, "Model has an error"); hSteCod=Medium.enthalpyOfCondensingGas(conv*time); der(hSteCod)=der(hSteSym); assert(abs(hSteCod-hSteSym) < 1E-2, "Model has an error"); hAirCod=Medium.enthalpyOfDryAir(conv*time); der(hAirCod)=der(hAirSym); assert(abs(hAirCod-hAirSym) < 1E-2, "Model has an error"); end MoistAirDerivativeCheck;

## Buildings.Obsolete.Media.PerfectGases.Examples.MoistAirTemperatureEnthalpyInversion

Model to check computation of h(T) and its inverse

### Information

Extends from Modelica.Icons.Example (Icon for runnable examples), Buildings.Media.Examples.BaseClasses.TestTemperatureEnthalpyInversion (Model to check computation of h(T) and its inverse).

### Parameters

Type | Name | Default | Description
--- | --- | --- | ---
replaceable package Medium | PartialCondensingGases |
Temperature | T0 | 273.15 + 20 | Temperature [K]

### Connectors

Type | Name | Description
--- | --- | ---
replaceable package Medium |

### Modelica definition

model MoistAirTemperatureEnthalpyInversion "Model to check computation of h(T) and its inverse" extends Modelica.Icons.Example; extends Buildings.Media.Examples.BaseClasses.TestTemperatureEnthalpyInversion ( redeclare package Medium = Buildings.Obsolete.Media.PerfectGases.MoistAir); end MoistAirTemperatureEnthalpyInversion;

## Buildings.Obsolete.Media.PerfectGases.Examples.TestMoistAir

### Information

This is a simple test for the medium model. It uses the test model described in Modelica.Media.UsersGuide.MediumDefinition.TestOfMedium.

Extends from Modelica.Icons.Example (Icon for runnable examples), Modelica.Media.Examples.Tests.Components.PartialTestModel (Basic test model to test a medium).

### Parameters

Type | Name | Default | Description
--- | --- | --- | ---
replaceable package Medium | PartialMedium | Medium model
AbsolutePressure | p_start | Medium.p_default | Initial value of pressure [Pa]
Temperature | T_start | Medium.T_default | Initial value of temperature [K]
SpecificEnthalpy | h_start | Medium.h_default | Initial value of specific enthalpy [J/kg]
Real | X_start[Medium.nX] | Medium.X_default | Initial value of mass fractions

### Connectors

Type | Name | Description
--- | --- | ---
replaceable package Medium | Medium model

### Modelica definition

model TestMoistAir extends Modelica.Icons.Example; extends Modelica.Media.Examples.Tests.Components.PartialTestModel( redeclare package Medium = Buildings.Obsolete.Media.PerfectGases.MoistAir); end TestMoistAir;