freestream

Description

The freestream is a generic boundary condition that provides a free-stream condition. It is a mixed condition derived from the inletOutlet condition, whereby the mode of operation switches between fixed (free stream) value and zero gradient based on the sign of the flux.

Usage

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

Boundary file

<patchName>
{
    type            patch;
    ...
}

Field file

<patchName>
{
    // Mandatory entries
    type            freestream;

    // Conditional entries

        // Option-1
        freestreamValue        <Field<Type>>;

        // Option-2
        freestreamBC           <fvPatchField<Type>>;

    // Optional entries
    phi             <word>;

    // Inherited entries;
    ...
}

where:

Property	Description	Type	Required	Default
type	Type name: freestream	word	yes	-
freestreamValue	Patch value	Field<Type>	choice	-
freestreamBC	Separate boundary condition	fvPatchField<Type>	choice	-
phi	Name of flux field	word	no	phi

The inherited entries are elaborated in:

• Foam::inletOutletFvPatchField

Further information

Tutorial:

• aerofoilNACA0012
• atmFlatTerrain

Source code:

• freestream

API:

• Foam::freestreamFvPatchField

History: Introduced in version 1.5