Description🔗
The ddt
function object computes the Eulerian
time derivative of an input volume field for time-variant simulations
(not appropriate to steady-state simulations).
Operands🔗
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
.
Usage🔗
Example of the ddt
function object
by using functions
sub-dictionary in system/controlDict
file:
ddt1
{
// Mandatory entries (unmodifiable)
type ddt;
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: ddt | 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 "ddt(<field>)"
Further information🔗
Tutorial:
Source code:
API:
History:
- Introduced in version v1712