Buildings.Utilities.Psychrometrics.Functions.BaseClasses
Package with base classes for Buildings.Utilities.Psychrometrics.Functions
Information
This package contains base classes that are used to construct the models in Buildings.Utilities.Psychrometrics.Functions.
Extends from Modelica.Icons.BasesPackage (Icon for packages containing base classes).
Package Content
| Name | Description |
|---|---|
 der_TDewPoi_pW_amb
|
Derivative of function TDewPoi_pW_amb |
| der_pW_TDewPoi
|
Derivative of function pW_TDewPoi |
| der_pW_TDewPoi_amb
|
Derivative of function pW_TDewPoi_amb |
| der_pW_X
|
Derivative of function pW_X |
| der_saturationPressureLiquid
|
Derivative of the function saturationPressureLiquid |
| der_sublimationPressureIce
|
Derivative of function sublimationPressureIce |
 Examples
|
Collection of models that illustrate model use and test models |
Buildings.Utilities.Psychrometrics.Functions.BaseClasses.der_TDewPoi_pW_amb
Derivative of function TDewPoi_pW_amb
Information
Derivative of dew point temperature calculation for moist air.
Extends from Modelica.Icons.Function (Icon for functions).
Inputs
| Type | Name | Default | Description |
|---|---|---|---|
| Pressure | p_w | Water vapor partial pressure [Pa] | |
| Real | dp_w | Differential of water vapor partial pressure |
Outputs
| Type | Name | Description |
|---|---|---|
| Real | dT | Differential of dew point temperature |
Modelica definition
function der_TDewPoi_pW_amb "Derivative of function TDewPoi_pW_amb"
extends Modelica.Icons.Function;
input Modelica.SIunits.Pressure p_w "Water vapor partial pressure";
input Real dp_w "Differential of water vapor partial pressure";
output Real dT "Differential of dew point temperature";
protected
constant Modelica.SIunits.Temperature T1=283.15 "First support point";
constant Modelica.SIunits.Temperature T2=293.15 "Second support point";
constant Modelica.SIunits.Pressure p1=1227.97 "First support point";
constant Modelica.SIunits.Pressure p2=2338.76 "Second support point";
constant Real a1=(Modelica.Math.log(p2) - Modelica.Math.log(p1)*T2/T1)/(1 -
T2/T1);
constant Real a2(unit="1/K")=(Modelica.Math.log(p1) - a1)/T1;
algorithm
dT := dp_w / (a2*p_w);
end der_TDewPoi_pW_amb;
Buildings.Utilities.Psychrometrics.Functions.BaseClasses.der_pW_TDewPoi
Derivative of function pW_TDewPoi
Information
Derivative of dew point temperature calculation for moist air above freezing temperature.
Extends from Modelica.Icons.Function (Icon for functions).
Inputs
| Type | Name | Default | Description |
|---|---|---|---|
| Temperature | T | Dew point temperature [K] | |
| Real | dT | Temperature differential |
Outputs
| Type | Name | Description |
|---|---|---|
| Real | dp_w | Differential of water vapor partial pressure |
Modelica definition
function der_pW_TDewPoi "Derivative of function pW_TDewPoi"
extends Modelica.Icons.Function;
input Modelica.SIunits.Temperature T "Dew point temperature";
input Real dT "Temperature differential";
output Real dp_w "Differential of water vapor partial pressure";
protected
constant Real C8=-5.800226E3;
constant Real C9=1.3914993E0;
constant Real C10=-4.8640239E-2;
constant Real C11=4.1764768E-5;
constant Real C12=-1.4452093E-8;
constant Real C13=6.5459673E0;
algorithm
dp_w := Modelica.Math.exp(C8/T + C9 + T*(C10 + T*(C11 + T*C12)) + C13*
Modelica.Math.log(T))*(-C8/T/T + C10 + 2*C11*T + 3*C12*T*T + C13/T)*dT;
end der_pW_TDewPoi;
Buildings.Utilities.Psychrometrics.Functions.BaseClasses.der_pW_TDewPoi_amb
Derivative of function pW_TDewPoi_amb
Information
Derivative of dew point temperature calculation for moist air.
Extends from Modelica.Icons.Function (Icon for functions).
Inputs
| Type | Name | Default | Description |
|---|---|---|---|
| Temperature | T | Dew point temperature [K] | |
| Real | dT |
Outputs
| Type | Name | Description |
|---|---|---|
| Real | dp_w | Differential of water vapor partial pressure |
Modelica definition
function der_pW_TDewPoi_amb "Derivative of function pW_TDewPoi_amb"
extends Modelica.Icons.Function;
input Modelica.SIunits.Temperature T "Dew point temperature";
input Real dT;
output Real dp_w "Differential of water vapor partial pressure";
protected
constant Modelica.SIunits.Temperature T1=283.15 "First support point";
constant Modelica.SIunits.Temperature T2=293.15 "Second support point";
constant Modelica.SIunits.Pressure p1=1227.97 "First support point";
constant Modelica.SIunits.Pressure p2=2338.76 "Second support point";
constant Real a1=(Modelica.Math.log(p2) - Modelica.Math.log(p1)*T2/T1)/(1 -
T2/T1);
constant Real a2(unit="1/K")=(Modelica.Math.log(p1) - a1)/T1;
algorithm
dp_w:=a2*Modelica.Math.exp(a1 + a2*T)*dT;
end der_pW_TDewPoi_amb;
Buildings.Utilities.Psychrometrics.Functions.BaseClasses.der_pW_X
Derivative of function pW_X
Information
Derivative of function Buildings.Utilities.Psychrometrics.Functions.pW_X.
Extends from Modelica.Icons.Function (Icon for functions).
Inputs
| Type | Name | Default | Description |
|---|---|---|---|
| MassFraction | X_w | Species concentration at dry bulb temperature [1] | |
| Pressure | p | 101325 | Total pressure [Pa] |
| Real | dX_w | Differential of species concentration at dry bulb temperature | |
| Real | dp | Differential of total pressure |
Outputs
| Type | Name | Description |
|---|---|---|
| Real | dp_w | Differential of water vapor pressure |
Modelica definition
function der_pW_X "Derivative of function pW_X"
extends Modelica.Icons.Function;
input Modelica.SIunits.MassFraction X_w(
min=0,
max=1,
nominal=0.01) "Species concentration at dry bulb temperature";
input Modelica.SIunits.Pressure p=101325 "Total pressure";
input Real dX_w
"Differential of species concentration at dry bulb temperature";
input Real dp "Differential of total pressure";
output Real dp_w "Differential of water vapor pressure";
protected
Modelica.SIunits.MassFraction x_w(nominal=0.01)
"Water mass fraction per mass of dry air";
Real dX_w_dX "Differential d (x_w) / d X_w";
algorithm
x_w := X_w/(1 - X_w);
dX_w_dX := 1/(1-X_w)^2;
dp_w := p * 0.62198 / (0.62198 + x_w)^2 * dX_w_dX * dX_w + x_w/(0.62198 + x_w) * dp;
end der_pW_X;
Buildings.Utilities.Psychrometrics.Functions.BaseClasses.der_saturationPressureLiquid
Derivative of the function saturationPressureLiquid
Information
Derivative of function Buildings.Utilities.Psychrometrics.Functions.saturationPressureLiquid.
Extends from Modelica.Icons.Function (Icon for functions).
Inputs
| Type | Name | Default | Description |
|---|---|---|---|
| Temperature | Tsat | Saturation temperature [K] | |
| Real | dTsat | Saturation temperature derivative [K/s] |
Outputs
| Type | Name | Description |
|---|---|---|
| Real | psat_der | Differential of saturation pressure [Pa/s] |
Modelica definition
function der_saturationPressureLiquid
"Derivative of the function saturationPressureLiquid"
extends Modelica.Icons.Function;
input Modelica.SIunits.Temperature Tsat "Saturation temperature";
input Real dTsat(unit="K/s") "Saturation temperature derivative";
output Real psat_der(unit="Pa/s") "Differential of saturation pressure";
algorithm
psat_der:=611.657*Modelica.Math.exp(17.2799 - 4102.99
/(Tsat - 35.719))*4102.99*dTsat/(Tsat - 35.719)^2;
end der_saturationPressureLiquid;
Buildings.Utilities.Psychrometrics.Functions.BaseClasses.der_sublimationPressureIce
Derivative of function sublimationPressureIce
Information
Derivative of function Buildings.Utilities.Psychrometrics.Functions.sublimationPressureIce.
Extends from Modelica.Icons.Function (Icon for functions).
Inputs
| Type | Name | Default | Description |
|---|---|---|---|
| Temperature | TSat | Saturation temperature [K] | |
| Real | dTsat | Sublimation temperature derivative [K/s] |
Outputs
| Type | Name | Description |
|---|---|---|
| Real | psat_der | Sublimation pressure derivative [Pa/s] |
Modelica definition
function der_sublimationPressureIce
"Derivative of function sublimationPressureIce"
extends Modelica.Icons.Function;
input Modelica.SIunits.Temperature TSat(displayUnit="degC",
nominal=300)
"Saturation temperature";
input Real dTsat(unit="K/s") "Sublimation temperature derivative";
output Real psat_der(unit="Pa/s") "Sublimation pressure derivative";
protected
Modelica.SIunits.Temperature TTriple=273.16 "Triple point temperature";
Modelica.SIunits.AbsolutePressure pTriple=611.657 "Triple point pressure";
Real r1=TSat/TTriple "Common subexpression 1";
Real r1_der=dTsat/TTriple "Derivative of common subexpression 1";
Real a[2]={-13.9281690,34.7078238} "Coefficients a[:]";
Real n[2]={-1.5,-1.25} "Coefficients n[:]";
algorithm
psat_der := exp(a[1] - a[1]*r1^n[1] + a[2] - a[2]*r1^n[2])*pTriple*(-(a[1]
*(r1^(n[1] - 1)*n[1]*r1_der)) - (a[2]*(r1^(n[2] - 1)*n[2]*r1_der)));
end der_sublimationPressureIce;