Description

The fluxSummary function object computes the volumetric- or mass-flux information across selections of face zones.

Statistics include:

positive flux:

\[ \phi_{+} = \sum \phi_{>0} \]
negative flux:

\[ \phi_{-} = \sum \phi_{<0} \]
net flux:

\[ \phi_{\mathrm{net}} = \sum \phi \]
absolute flux:

\[ \phi_{\mathrm{abs}} = \sum |{\phi}| \]

Operands

Operand	Type	Location
input	-	-
output file	dat	`$FOAM_CASE/postProcessing/<FO>/<time>/<faceN>`
output field	-	-

Usage

Example of the fluxSummary function object by using functions sub-dictionary in system/controlDict file:

fluxSummary1
{
    // Mandatory entries (unmodifiable)
    type            fluxSummary;
    libs            (fieldFunctionObjects);

    // Mandatory entries (runtime modifiable)
    mode            cellZoneAndDirection;
    cellZoneAndDirection
    (
        (porosity (1 0 0))
    );

    // Optional entries  (runtime modifiable)
    phi             phi;
    scaleFactor     1.0;
    tolerance       0.8;

    // Optional (inherited) entries
    writePrecision  8;
    writeToFile     true;
    useUserTime     true;
    region          region0;
    enabled         true;
    log             true;
    timeStart       0;
    timeEnd         1000;
    executeControl  timeStep;
    executeInterval 1;
    writeControl    timeStep;
    writeInterval   1;
}

where the entries mean:

Property	Description	Type	Required	Default
type	Type name: fluxSummary	word	yes	-
libs	Library name: fieldFunctionObjects	word	yes	-
mode	Mode to generate faces to test	word	yes	-
phi	Name of surface flux field	word	no	phi
scaleFactor	Factor to scale results	scalar	no	1.0
tolerance	Tolerance for reference direction	scalar	no	0.8

Options for the mode entry:

faceZone
faceZoneAndDirection | faceZone with prescribed positive direction
cellZoneAndDirection | cellZone with prescribed positive direction
surface
surfaceAndDirection

The inherited entries are elaborated in:

Usage by the postProcess utility is not available.

Notes on entries

For surface and direction, phi=U can be used for determining the fluxes.
In case of mode=cellZoneAndDirection, faces bounding the cellZone are extracted and processed.

Further information

Tutorial:

$FOAM_TUTORIALS/incompressible/pisoFoam/RAS/cavity

Source code:

Foam::functionObjects::fluxSummary

History

Introduced in version v1612+

Table of Contents

Description

Operands

Usage

Notes on entries

Further information