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Description

The timeVaryingMassSorption is a boundary condition that provides a first order fixed-value condition for a given scalar field to model time-dependent adsorption-desoprtion processes to be used with the interfaceOxideRate mass model

\[\frac{d c}{d t} = k_{abs} w (c_{int} - c_{p_{w}}) + k_{des} (c_{p_{w}} - c_{int})\] \[w = \max(1 - c_{p_{w}}/max, 0)\]

where:

Property Description
\(c_{int}\) Concentration at cell
\(c_{p_{w}}\) Concentration at wall
\(k_{abs}\) Adsorption rate constant [1/s]
\(k_{des}\) Desorption rate constant [1/s]
\(w\) Weight function
\(max\) Max concentration at wall

Usage

The condition requires entries in both the boundary and field files.

Boundary file 

<patchName>
{
    type            patch;
    ...
}

Field file 

<patchName>
{
    type        timeVaryingMassSorption;
    kbas        <scalar>;
    max         <scalar>;

    // Optional entries
    kdes        <scalar>;

    // Inherited entries
    ...
}

where:

Property Description Type Required Default
type Type name: timeVaryingAdsorption word yes -
kbas Adsorption rate constant scalar yes -
max Maximum concentation at wall scalar yes -
kdes Desorption rate constant scalar no 0

The inherited entries are elaborated in:

  • fixedValueFvPatchField.H

Further information

Tutorial:

Source code:

API:

History:

  • Introduced in version v2106