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Description

The turbulenceFields function object computes various turbulence-related quantities that are not typically output during calculations, including:

  • k: Turbulent kinetic energy
  • epsilon: Turbulent kinetic energy dissipation rate
  • omega: Specific dissipation rate
  • R: Reynolds stress tensor
  • L: Integral-length/Mixing-length scale
  • I: Turbulence intensity
  • nuTilda: Modified turbulent viscosity

Additional field selections for incompressible cases:

  • nut: Turbulent (edy) kinematic viscosity
  • nuEff: Effective kinematic viscosity (laminar + turbulent contributions)
  • devReff: Deviatoric stress tensor

Additional field selections for compressible cases:

  • mut: Turbulent (eddy) dynamic viscosity
  • muEff: Effective dynamic viscosity (laminar + turbulent contributions)
  • alphat: Thermal eddy diffusivity
  • alphaEff: Effective eddy thermal diffusivity
  • devRhoReff: Deviatoric stress tensor

These fields are stored on the mesh database for further post-processing, and written as regular volume fields at write intervals.

Operands

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

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

Usage

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

turbulenceFields1
{
    // Mandatory entries (unmodifiable)
    type            turbulenceFields;
    libs            (fieldFunctionObjects);

    // Mandatory entries (runtime modifiable)
    // Either field or fields entries
    fields          (R devRhoReff);
    field           R;

    // 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: turbulenceFields word yes -
libs Library name: fieldFunctionObjects word yes -
fields Names of fields to store (see below) wordList yes -
field Name of a field to store (see below) word yes -

The inherited entries are elaborated in:

Example by using the postProcess utility:

<solver> -postProcess -func turbulenceFields

Sample output

Fields stored on the mesh database with the prefix turbulenceProperties:, e.g.

turbulenceProperties:mut
turbulenceProperties:R
turbulenceProperties:devRhoReff

and written to the standard time directories according to the writeControl setting.

Further information

Tutorial:

Source code:

API:

History: