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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

NameDescription
Buildings.Utilities.Psychrometrics.Functions.BaseClasses.Examples Examples Collection of models that illustrate model use and test models
Buildings.Utilities.Psychrometrics.Functions.BaseClasses.der_pW_X der_pW_X Derivative of function pW_X
Buildings.Utilities.Psychrometrics.Functions.BaseClasses.der_pW_TDewPoi der_pW_TDewPoi Derivative of function pW_TDewPoi
Buildings.Utilities.Psychrometrics.Functions.BaseClasses.der_pW_TDewPoi_amb der_pW_TDewPoi_amb Derivative of function pW_TDewPoi_amb
Buildings.Utilities.Psychrometrics.Functions.BaseClasses.der_TDewPoi_pW_amb der_TDewPoi_pW_amb Derivative of function TDewPoi_pW_amb
Buildings.Utilities.Psychrometrics.Functions.BaseClasses.pW_TDewPoi_amb pW_TDewPoi_amb Partial function to compute the water vapor partial pressure for a given dew point temperature of moist air and its inverse

Buildings.Utilities.Psychrometrics.Functions.BaseClasses.der_pW_X

Derivative of function pW_X

Information

Derivative of function Buildings.Utilities.Psychrometrics.Functions.pW_X.

Inputs

TypeNameDefaultDescription
MassFractionX_w Species concentration at dry bulb temperature [1]
Pressurep101325Total pressure [Pa]
RealdX_w Differential of species concentration at dry bulb temperature
Realdp Differential of total pressure

Outputs

TypeNameDescription
Realdp_wDifferential of water vapor pressure

Modelica definition

function der_pW_X "Derivative of function pW_X"

  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_pW_TDewPoi

Derivative of function pW_TDewPoi

Information

Derivative of dew point temperature calculation for moist air above freezing temperature.

Inputs

TypeNameDefaultDescription
TemperatureT Dew point temperature [K]
RealdT Temperature differential

Outputs

TypeNameDescription
Realdp_wDifferential of water vapor partial pressure

Modelica definition

function der_pW_TDewPoi "Derivative of function pW_TDewPoi"

  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 Buildings.Utilities.Psychrometrics.Functions.BaseClasses.pW_TDewPoi_amb (Partial function to compute the water vapor partial pressure for a given dew point temperature of moist air and its inverse).

Inputs

TypeNameDefaultDescription
TemperatureT Dew point temperature [K]
RealdT  

Outputs

TypeNameDescription
Realdp_wDifferential of water vapor partial pressure

Modelica definition

function der_pW_TDewPoi_amb "Derivative of function pW_TDewPoi_amb"
  extends Buildings.Utilities.Psychrometrics.Functions.BaseClasses.pW_TDewPoi_amb;
  input Modelica.SIunits.Temperature T "Dew point temperature";
  input Real dT;
  output Real dp_w "Differential of water vapor partial pressure";
algorithm 
  dp_w:=a2*Modelica.Math.exp(a1 + a2*T)*dT;

end der_pW_TDewPoi_amb;

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 Buildings.Utilities.Psychrometrics.Functions.BaseClasses.pW_TDewPoi_amb (Partial function to compute the water vapor partial pressure for a given dew point temperature of moist air and its inverse).

Inputs

TypeNameDefaultDescription
Pressurep_w Water vapor partial pressure [Pa]
Realdp_w Differential of water vapor partial pressure

Outputs

TypeNameDescription
RealdTDifferential of dew point temperature

Modelica definition

function der_TDewPoi_pW_amb "Derivative of function TDewPoi_pW_amb"
  extends Buildings.Utilities.Psychrometrics.Functions.BaseClasses.pW_TDewPoi_amb;

  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";
algorithm 
  dT := dp_w / a2 / p_w;

end der_TDewPoi_pW_amb;

Buildings.Utilities.Psychrometrics.Functions.BaseClasses.pW_TDewPoi_amb

Partial function to compute the water vapor partial pressure for a given dew point temperature of moist air and its inverse

Information

Partial function to compute the dew point temperature for moist air between 0 degC and 30 degC, and for its inverse function.

Modelica definition

partial function pW_TDewPoi_amb 
  "Partial function to compute the water vapor partial pressure for a given dew point temperature of moist air and its inverse"

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;

end pW_TDewPoi_amb;

Automatically generated Thu Oct 24 15:13:45 2013.