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

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## Buildings.Utilities.Psychrometrics.Functions.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.Utilities.Psychrometrics.Functions.

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

### Package Content

Name | Description
--- | ---
Density_pTX | Model to test density_pTX
SaturationPressure | Model to test the saturationPressure function
X_pSatpphi | Model to test X_pSatpphi function
pW_TDewPoi | Model to test pW_TDewPoi and its inverse function
pW_TDewPoi_comparison | Model to test the approximation for pW_TDewPoi and its inverse function
pW_X | Model to test pW_X and its inverse function
phi_pTX | Model to test phi_pTX

## Buildings.Utilities.Psychrometrics.Functions.Examples.Density_pTX

Model to test density_pTX

### Information

Model that tests the implementation of Buildings.Utilities.Psychrometrics.Functions.density_pTX.

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

### Parameters

Type | Name | Default | Description
--- | --- | --- | ---
Pressure | p | 101325 | Pressure of the medium [Pa]

### Modelica definition

model Density_pTX "Model to test density_pTX" extends Modelica.Icons.Example; parameter Modelica.SIunits.Pressure p = 101325 "Pressure of the medium"; Modelica.SIunits.Temperature T "Temperature"; Modelica.SIunits.MassFraction X_w "Mass fraction"; Modelica.SIunits.Density d "Mass density"; constant Real convT(unit="1/s") = 0.999 "Conversion factor"; constant Real convX(unit="1/s") = 0.02 "Conversion factor"; equation if time < 0.5 then X_w = convX*time; T = 293.15; else X_w = 0.5*convX; T = 293.15+convT*(time-0.5)*10; end if; d = Buildings.Utilities.Psychrometrics.Functions.density_pTX(p=p, T=T, X_w=X_w); end Density_pTX;

## Buildings.Utilities.Psychrometrics.Functions.Examples.SaturationPressure

Model to test the saturationPressure function

### Information

This example computes the saturation pressure of water.

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

### Parameters

Type | Name | Default | Description
--- | --- | --- | ---
Temperature | TMin | 190 | Temperature [K]
Temperature | TMax | 373.16 | Temperature [K]

### Modelica definition

model SaturationPressure "Model to test the saturationPressure function" extends Modelica.Icons.Example; parameter Modelica.SIunits.Temperature TMin = 190 "Temperature"; parameter Modelica.SIunits.Temperature TMax = 373.16 "Temperature"; Modelica.SIunits.Temperature T "Temperature"; Modelica.SIunits.AbsolutePressure pSat "Saturation pressure"; constant Real conv(unit="1/s") = 1 "Conversion factor"; equation T = TMin + conv*time * (TMax-TMin); pSat = Buildings.Utilities.Psychrometrics.Functions.saturationPressure(T); end SaturationPressure;

## Buildings.Utilities.Psychrometrics.Functions.Examples.X_pSatpphi

Model to test X_pSatpphi function

### Information

This example computes the water content of air for a relative humidity between 0 and 100%, a temperature of 20ˆC and atmospheric pressure.

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

### Parameters

Type | Name | Default | Description
--- | --- | --- | ---
Temperature | T | 293.15 | Temperature [K]
Pressure | p | 101325 | Pressure of the fluid [Pa]

### Modelica definition

model X_pSatpphi "Model to test X_pSatpphi function" extends Modelica.Icons.Example; package Medium = Buildings.Media.Air "Medium model"; parameter Modelica.SIunits.Temperature T = 293.15 "Temperature"; parameter Modelica.SIunits.Pressure p = 101325 "Pressure of the fluid"; Modelica.SIunits.AbsolutePressure pSat "Saturation pressure"; Real phi(min=0, max=1) "Relative humidity"; Modelica.SIunits.MassFraction X_w( min=0, max=1, nominal=0.01) "Water vapor concentration per total mass of air"; constant Real conv(unit="1/s") = 1 "Conversion factor"; equation phi = time*conv; pSat = Medium.saturationPressure(T); X_w = Buildings.Utilities.Psychrometrics.Functions.X_pSatpphi(pSat=pSat, p=p, phi=phi); end X_pSatpphi;

## Buildings.Utilities.Psychrometrics.Functions.Examples.pW_TDewPoi

Model to test pW_TDewPoi and its inverse function

### Information

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

### Modelica definition

model pW_TDewPoi "Model to test pW_TDewPoi and its inverse function" extends Modelica.Icons.Example; Modelica.SIunits.Temperature T "Dew point temperature"; Modelica.SIunits.Temperature TInv "Dew point temperature"; Modelica.SIunits.TemperatureDifference dT "Difference between temperatures"; Modelica.SIunits.Pressure p_w "Water vapor partial pressure"; constant Real conv(unit="K/s") = 100 "Conversion factor"; equation T = conv*time + 273.15; p_w = Buildings.Utilities.Psychrometrics.Functions.pW_TDewPoi(T); TInv = Buildings.Utilities.Psychrometrics.Functions.TDewPoi_pW(p_w); dT = T - TInv; assert(abs(dT) < 10E-12, "Error in function implementation."); end pW_TDewPoi;

## Buildings.Utilities.Psychrometrics.Functions.Examples.pW_TDewPoi_comparison

Model to test the approximation for pW_TDewPoi and its inverse function

### Information

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

### Modelica definition

model pW_TDewPoi_comparison "Model to test the approximation for pW_TDewPoi and its inverse function" extends Modelica.Icons.Example; Modelica.SIunits.Temperature T "Dew point temperature"; Modelica.SIunits.Temperature TInv "Dew point temperature"; Modelica.SIunits.TemperatureDifference dT "Difference between temperatures"; Modelica.SIunits.Pressure p_w_ashrae "Water vapor partial pressure according to the ASHRAE handbook"; Modelica.SIunits.Pressure p_w "Water vapor partial pressure"; constant Real conv(unit="K/s") = 30 "Conversion factor"; Real r_p "Ratio of the two approximations"; equation T = conv*time + 273.15; p_w_ashrae = Buildings.Utilities.Psychrometrics.Functions.pW_TDewPoi(T); p_w = Buildings.Utilities.Psychrometrics.Functions.pW_TDewPoi_amb(T); r_p = p_w_ashrae/p_w; p_w = Buildings.Utilities.Psychrometrics.Functions.pW_TDewPoi_amb(TInv); dT = T - TInv; assert(abs(dT) < 10E-12, "Error in function implementation."); end pW_TDewPoi_comparison;

## Buildings.Utilities.Psychrometrics.Functions.Examples.pW_X

Model to test pW_X and its inverse function

### Information

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

### Modelica definition

model pW_X "Model to test pW_X and its inverse function" extends Modelica.Icons.Example; Modelica.SIunits.MassFraction X "Mass fraction"; Modelica.SIunits.MassFraction XInv "Mass fraction"; Modelica.SIunits.MassFraction dX "Difference between mass fraction"; Modelica.SIunits.Pressure p_w "Water vapor partial pressure"; constant Real conv(unit="1/s") = 0.999 "Conversion factor"; equation X = conv*time; p_w = Buildings.Utilities.Psychrometrics.Functions.pW_X(X); XInv = Buildings.Utilities.Psychrometrics.Functions.X_pW(p_w); dX = X - XInv; assert(abs(dX) < 10E-12, "Error in function implementation."); end pW_X;

## Buildings.Utilities.Psychrometrics.Functions.Examples.phi_pTX

Model to test phi_pTX

### Information

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

### Parameters

Type | Name | Default | Description
--- | --- | --- | ---
Pressure | p | 101325 | Pressure of the medium [Pa]

### Modelica definition

model phi_pTX "Model to test phi_pTX" extends Modelica.Icons.Example; parameter Modelica.SIunits.Pressure p = 101325 "Pressure of the medium"; Modelica.SIunits.Temperature T "Temperature"; Modelica.SIunits.MassFraction X_w "Mass fraction"; Real phi "Relative humidity"; constant Real convT(unit="1/s") = 0.999 "Conversion factor"; constant Real convX(unit="1/s") = 0.02 "Conversion factor"; equation if time < 0.5 then X_w = convX*time; T = 293.15; else X_w = 0.5*convX; T = 293.15+convT*(time-0.5)*10; end if; phi = Buildings.Utilities.Psychrometrics.Functions.phi_pTX(p=p, T=T, X_w=X_w); end phi_pTX;