kLowReWallFunction

Description

The kLowReWallFunction is boundary condition that provides a wall function for the turbulent kinetic energy (i.e. k) for low- and high-Reynolds number simulations.

Viscous and inertial sublayer predictions for \c k are blended in a stepwise manner:

$$k = k_{log} \qquad if \quad y^+ > y^+_{intersection}$$ $$k = k_{vis} \qquad if \quad y^+ <= y^+_{intersection}$$

where:

Property	Description
$k_{vis}$	k prediction in the viscous sublayer
$k_{log}$	k prediction in the inertial sublayer
$y^+$	Estimated wall-normal height of the cell centre in wall units
$y^+_{intersection}$	Estimated $$$y^+$$ where sublayers intersect

Usage

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

Boundary file

<patchName>
{
    type            wall;
    ...
}

Field file

<patchName>
{
    // Mandatory entries
    type            kLowReWallFunction;

    // Optional entries
    Ceps2           <scalar>;
    Ck              <scalar>;
    Bk              <scalar>;
    C               <scalar>;

    // Inherited entries
    ...
}

where:

Property	Description	Type	Required	Default
type	Type name: kLowReWallFunction	word	yes	-
Ceps2	Model coefficient	scalar	no	1.9
Ck	Model coefficient	scalar	no	-0.416
Bk	Model coefficient	scalar	no	8.366
C	Model coefficient	scalar	no	11.0

The inherited entries are elaborated in:

• wallFunctionCoefficients.H
• fixedValueFvPatchField.H

Further information

Tutorial:

• N/A

Source code:

• kLowReWallFunction

API:

• Foam::kLowReWallFunctionFvPatchScalarField

History: Introduced in version 2.4.0