The columnAverage function object computes the arithmetic average of given quantities along columns of cells in a given direction for structured-like layered meshes. It is, for example, useful for channel-like cases where spanwise average of a field is desired. However, the columnAverage function object does not operate on arbitrary unstructured meshes.

The columnAverage function object, for each patch face, calculates the average value of all cells attached in the patch face normal direction, and then pushes the average value back to all cells in the column.

The columnAverage function object can be applied to any volume fields, generating a volume field. However, the operation cannot be applied onto surface fields, e.g wallShearStress.


Operand Type Location
input vol<Type>Field $FOAM_CASE/<time>/<inpField>
output file - -
output field vol<Type>Field $FOAM_CASE/<time>/<outField>

where <Type>=Scalar/Vector/SphericalTensor/SymmTensor/Tensor.


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

    // Mandatory entries (unmodifiable)
    type            columnAverage;
    libs            (fieldFunctionObjects);

    // Mandatory entries (runtime modifiable)
    patches         (<patch1> <patch2> ... <patchN>)
    fields          (<field1> <field2> ... <fieldN>);

    // Optional (inherited) entries
    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: columnAverage word yes -
libs Library name: fieldFunctionObjects word yes -
patches Names of patches to collapse onto word yes -
fields Names of the operand fields word yes -

The inherited entries are elaborated in:

Usage by the postProcess utility is not available.

Further information


Source code:



  • Introduced in version v1812