Turbulence properties and boundary conditions in OpenFOAM

To know turbulence models in OpenFOAM, please look at OpenFOAM User Guide 7.2

Reynolds-averaged Navier–Stokes (RANS)

NASA's Turbulence Modeling Resource 


Boundary Conditions:
INLET
1.    turbulentIntensityKineticEnergyInlet for k in the inlet (under that you make the description of the intensity and the value)
2.    turbulentMixingLengthFrequencyInlet for omega in the inlet (then description mixing length, k and value)
3.    turbulentMixingLengthDissipationRateInlet for epsilon in the inlet (then description mixing length and value)
4.    fixedValue
EXAMPLE:
inlet
{
type turbulentIntensityKineticEnergyInlet;
intensity 0.02;
value uniform 0.0006;
}
To calculate the initial values of k, epsilon and w, read Turbulence free-stream boundary conditions
WALL
With Wall Function (y+ > 1)
1.      kqRWallFunction for k
2.      epsilonWallFunction for epsilon
3.      omegaWallFunction for omega
4.      nutWallFunction or nutSpalartAllmarasWallFunction
Without Wall Function (y+ < 1)
1.    fixedValue for k, epsilon and omega use very small number like 1e-10 as value.

Large eddy simulation (LES)

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