FCSys.Regions.CaCLs

Cathode catalyst layers

Information

Extends from Modelica.Icons.Package (Icon for standard packages).

Package Content

Name	Description
CaCL	Cathode catalyst layer
CaCGDL	Integrated cathode catalyst/gas diffusion layer

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FCSys.Regions.CaCLs.CaCL

Cathode catalyst layer

Information

This model represents the cathode catalyst layer of a PEMFC. It is identical to the anode catalyst layer except for the included species, the exchange current density (J^o), and the activation energy (). For more information, please see the anCL model.

Extends from Region (Base model for a 3D array of subregions).

Parameters

Type	Name	Default	Description
replaceable model Subregion		Subregions.Subregion (common…	Base subregion model
CurrentAreic	J0	0.023*U.mA/U.cm^2	Exchange current density @ 300 K [N/(L2.T)]
Geometry
Length	L_x[:]	{28.7}*U.um	Lengths along the x axis [L]
Length	L_y[:]	{8}*U.cm	Lengths along the y axis [L]
Length	L_z[:]	{6.25}*U.cm	Lengths across the z axis [L]
NumberAbsolute	epsilon	0.4	Porosity [1]
Assumptions
Included transport axes
Boolean	inclTransX	true	X
Boolean	inclTransY	false	Y
Boolean	inclTransZ	false	Z

Connectors

Type	Name	Description
replaceable model Subregion		Base subregion model
BoundaryBus	xNegative[n_y, n_z]	Negative boundary along the x axis
BoundaryBus	xPositive[n_y, n_z]	Positive boundary along the x axis
BoundaryBus	yNegative[n_x, n_z]	Negative boundary along the y axis
BoundaryBus	yPositive[n_x, n_z]	Positive boundary along the y axis
BoundaryBus	zNegative[n_x, n_y]	Negative boundary along the z axis
BoundaryBus	zPositive[n_x, n_y]	Positive boundary along the z axis

Modelica definition

model CaCL "Cathode catalyst layer"
  import Modelica.Constants.inf;
  // extends FCSys.Icons.Names.Top4;

  extends Region(
    L_x={28.7}*U.um,
    L_y={8}*U.cm,
    L_z={6.25}*U.cm,
    final inclTransX=true,
    inclTransY=false,
    inclTransZ=false,
    redeclare replaceable model Subregion = Subregions.Subregion (
        common(k_Q=0),
        gasLiq(k_Q=inf),
        gas(
          common(k_Q=inf),
          k=fill(epsilon^(-0.5), 3),
          inclH2O=true,
          inclN2=true,
          inclO2=true,
          H2O(
            initEnergy=Init.none,
            upstreamX=false,
            phi(each stateSelect=StateSelect.always, each fixed=true),
            final zeta=0),
          N2(
            initEnergy=Init.none,
            upstreamX=false,
            final zeta=0),
          O2(
            initEnergy=Init.none,
            upstreamX=false,
            I(each stateSelect=StateSelect.always, each fixed=true),
            final zeta=0,
            p_stop=12*U.Pa)),
        graphite(
          k=fill((0.5*(1 - epsilon))^(-0.5), 3),
          'inclC+'=true,
          'incle-'=true,
          'incle-Transfer'=true,
          'C+'(theta=U.m*U.K/(1.18*U.W)*(0.5*(1 - epsilon))^1.5, epsilon=0.5*(1 -
                epsilon)),
          'e-'(sigma=40*U.S/(12*U.cm)/(0.5*(1 - epsilon))^1.5),
          'e-Transfer'(E_A=0.75*U.V)),
        ionomer(
          k=fill((0.5*(1 - epsilon))^(-0.5), 3),
          'inclSO3-'=true,
          'inclH+'=true,
          inclH2O=true,
          'SO3-'(epsilon=0.5*(1 - epsilon), T(each fixed=false, each 
                stateSelect=StateSelect.default)),
          'H+'(initEnergy=Init.none, sigma=0.1*U.S/U.cm),
          H2O(initEnergy=Init.none, phi(each stateSelect=StateSelect.always, 
                each fixed=true))),
        liquid(
          k=fill(epsilon^(-0.5), 3),
          inclH2O=true,
          H2O(
            upstreamX=false,
            epsilon_IC=1e-5,
            phi(each stateSelect=StateSelect.always, each fixed=true),
            each initEnergy=Init.none,
            N0=0.1*U.C,
            T(each stateSelect=StateSelect.default))),
        volume(inclCapillary=true,capillary(R=5*U.um))),
    subregions(graphite('e-Transfer'(final I0=J0*subregions.A[Axis.x]))));

  // See the documentation layer of Phases.PartialPhase regarding the
  // settings of k for each phase.

  parameter Q.NumberAbsolute epsilon(nominal=1) = 0.4 "Porosity";

  parameter Q.CurrentAreic J0(min=0) = 0.023*U.mA/U.cm^2 
    "Exchange current density @ 300 K";

protected 
  outer Conditions.Environment environment "Environmental conditions";

initial equation 

end CaCL;

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FCSys.Regions.CaCLs.CaCGDL

Integrated cathode catalyst/gas diffusion layer

Information

The default thickness is the total thickness of CaCL and CaGDL.

For more information, please see the CaCL model.

Extends from CaCLs.CaCL (Cathode catalyst layer).

Parameters

Type	Name	Default	Description
replaceable model Subregion		Subregions.Subregion (common…	Base subregion model
CurrentAreic	J0	0.023*U.mA/U.cm^2	Exchange current density @ 300 K [N/(L2.T)]
Geometry
Length	L_x[:]	{(28.7*U.um + 0.235*U.mm)}	Lengths along the x axis [L]
Length	L_y[:]	{8}*U.cm	Lengths along the y axis [L]
Length	L_z[:]	{6.25}*U.cm	Lengths across the z axis [L]
NumberAbsolute	epsilon	0.16	Porosity [1]
Assumptions
Included transport axes
Boolean	inclTransY	false	Y
Boolean	inclTransZ	false	Z

Connectors

Type	Name	Description
BoundaryBus	xNegative[n_y, n_z]	Negative boundary along the x axis
BoundaryBus	xPositive[n_y, n_z]	Positive boundary along the x axis
BoundaryBus	yNegative[n_x, n_z]	Negative boundary along the y axis
BoundaryBus	yPositive[n_x, n_z]	Positive boundary along the y axis
BoundaryBus	zNegative[n_x, n_y]	Negative boundary along the z axis
BoundaryBus	zPositive[n_x, n_y]	Positive boundary along the z axis

Modelica definition

model CaCGDL "Integrated cathode catalyst/gas diffusion layer"
  import Modelica.Constants.inf;

  extends CaCLs.CaCL(
    L_x={(28.7*U.um + 0.235*U.mm)},
    epsilon=0.16,
    subregions(
      gas(
        H2O(each final eta=0),
        N2(each final eta=0),
        O2(each final eta=0)),
      ionomer('H+_H2O'(each k_Phi={1,1,1}),'H+'(each sigma=0.8*U.S/U.cm)),
      liquid(H2O(each final eta=0))));

end CaCGDL;