FCSys.Characteristics.MobilityFactors.BaseClasses

Base classes (generally not for direct use)

Information

Extends from Modelica.Icons.BasesPackage (Icon for packages containing base classes).

Package Content

Name	Description
k	Binary mobility factor
pDstar_nonpolar	[Slattery1958] reduced pressure-diffusivity product for nonpolar species
pDstar_polar	[Slattery1958] reduced pressure-diffusivity product for polar species

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FCSys.Characteristics.MobilityFactors.BaseClasses.k

Binary mobility factor

Information

v_A and v_B are given as inputs even though they can be calculated from T, p_A, and p_B because it may be desirable to leave v_A and v_B constant while varying p_A and p_B.

This function is based on eq. 5 from [Slattery1958].

Inputs

Type	Name	Default	Description
TemperatureAbsolute	T	298.15*U.K	Temperature [L2.M/(N.T2)]
PressureAbsolute	p_A	U.atm	Pressure of the 1st species [M/(L.T2)]
PressureAbsolute	p_B	U.atm	Pressure of the 2nd species [M/(L.T2)]
VolumeSpecific	v_A	298.15*U.K/A.p0	Specific volume of the 1st species [L3/N]
VolumeSpecific	v_B	298.15*U.K/B.p0	Specific volume of the 2nd species [L3/N]
replaceable function pDstar		MobilityFactors.BaseClasses….	Reduced pressure-diffusivity product
replaceable package A		Characteristics.BaseClasses….	Characteristic data of the 2nd species
replaceable package B		Characteristics.BaseClasses….	Characteristic data of the 2nd species
TemperatureAbsolute	T_crit		Geometric mean of the critical temperatures [L2.M/(N.T2)]
PressureAbsolute	p_crit		Geometric mean of the critical pressures [M/(L.T2)]

Outputs

Type	Name	Description
replaceable function pDstar		Reduced pressure-diffusivity product
replaceable package A		Characteristic data of the 2nd species
replaceable package B		Characteristic data of the 2nd species
NumberAbsolute	k_Phi	Binary mobility factor [1]

Modelica definition

function k "Binary mobility factor"
  import harmonicMean = FCSys.Utilities.Means.harmonic;

  input Q.TemperatureAbsolute T=298.15*U.K "Temperature";
  input Q.PressureAbsolute p_A=U.atm 
    "Pressure of the 1st species";
  input Q.PressureAbsolute p_B=U.atm 
    "Pressure of the 2nd species";
  input Q.VolumeSpecific v_A=298.15*U.K/A.p0 
    "Specific volume of the 1st species";
  input Q.VolumeSpecific v_B=298.15*U.K/B.p0 
    "Specific volume of the 2nd species";
  replaceable function pDstar = MobilityFactors.BaseClasses.pDstar_nonpolar 
    "Reduced pressure-diffusivity product";
  replaceable package A = Characteristics.BaseClasses.Characteristic 
    "Characteristic data of the 2nd species";
  replaceable package B = Characteristics.BaseClasses.Characteristic 
    "Characteristic data of the 2nd species";

  input Q.TemperatureAbsolute T_crit 
    "Geometric mean of the critical temperatures";
  input Q.PressureAbsolute p_crit "Geometric mean of the critical pressures";
  output Q.NumberAbsolute k_Phi "Binary mobility factor";

algorithm 
  k_Phi := pDstar(T/T_crit)*p_crit^(2/3)*(T_crit*U.mol/U.K)^(5/6)*(U.atm/U.q)^(1
    /3)*U.cm^2/U.s/sqrt(harmonicMean({A.m,B.m})*U.g)/(p_A*B.D(T, v_A) + p_B*A.D
    (T, v_B)) 
    "Based on [Slattery1958, eq. 5] and the exchange equations in FCSys.Species.Species";

end k;

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FCSys.Characteristics.MobilityFactors.BaseClasses.pDstar_nonpolar

[Slattery1958] reduced pressure-diffusivity product for nonpolar species

Information

This function is based on eq. 4 from [Slattery1958].

Inputs

Type	Name	Default	Description
TemperatureAbsolute	Tstar	1	Ratio of temperature to the geometric mean of the critical temperatures [L2.M/(N.T2)]

Outputs

Type	Name	Description
NumberAbsolute	pDstar	Reduced pressure-diffusivity product [1]

Modelica definition

function pDstar_nonpolar 
  "[Slattery1958] reduced pressure-diffusivity product for nonpolar species"
  input Q.TemperatureAbsolute Tstar=1 
    "Ratio of temperature to the geometric mean of the critical temperatures";
  output Q.NumberAbsolute pDstar "Reduced pressure-diffusivity product";

algorithm 
  pDstar := 3.882e-4*Tstar^1.823;
end pDstar_nonpolar;

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FCSys.Characteristics.MobilityFactors.BaseClasses.pDstar_polar

[Slattery1958] reduced pressure-diffusivity product for polar species

Information

This function is based on eq. 9 from [Slattery1958].

Inputs

Type	Name	Default	Description
TemperatureAbsolute	Tstar	1	Ratio of temperature to the geometric mean of the critical temperatures [L2.M/(N.T2)]

Outputs

Type	Name	Description
NumberAbsolute	pDstar	Reduced pressure-diffusivity product [1]

Modelica definition

function pDstar_polar 
  "[Slattery1958] reduced pressure-diffusivity product for polar species"
  input Q.TemperatureAbsolute Tstar=1 
    "Ratio of temperature to the geometric mean of the critical temperatures";
  output Q.NumberAbsolute pDstar "Reduced pressure-diffusivity product";

algorithm 
  pDstar := 5.148e-4*Tstar^2.334;
end pDstar_polar;