Description🔗
The grad
function object computes
the gradient of an input field.
The operation is limited to scalar and vector volume or surface fields, and the output is a volume vector or tensor field.
Operands🔗
Operand | Type | Location |
---|---|---|
input | {vol,surface}{Scalar,Vector}Field |
$FOAM_CASE/<time>/<inpField> |
output file | - | - |
output field | vol{Vector,Tensor}Field |
$FOAM_CASE/<time>/<outField> |
Usage🔗
Example of the grad
function object
by using functions
sub-dictionary in system/controlDict
file:
grad1
{
// Mandatory entries (unmodifiable)
type grad;
libs (fieldFunctionObjects);
// Mandatory (inherited) entries (runtime modifiable)
field <field>;
// Optional (inherited) entries
result <fieldResult>;
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: grad | word | yes | - |
libs | Library name: fieldFunctionObjects | word | yes | - |
field | Name of the operand field | word | yes | - |
The inherited entries are elaborated in:
Example by using the postProcess
utility:
postProcess -func "grad(<field>)"
Further information🔗
Tutorial:
Source code:
API:
History:
- Introduced in version v1606+