How to set up a mixing model

The setup of turbulent mixing models is done in the mixingProperties dictionary of the corresponding case.

Activating the mixing model

The mixing model is activated using the mixingModel keyword and setting it to the desired model type:

mixingModel turbulentMixing;

Sub-models are specified in the corresponding Coeff dictionary.

turbulentMixingCoeffs
{

    ….

}

Selecting the diffusion model

The diffusion model is selected in the diffusionModel sub-dictionary:

diffusionModel
{
    diffusionModel turbulentDiffusion;
    gammaLam gammaLam [ 0 2 -1 0 0 0 0 ] 1.0e-6;
    Sc 0.7;
}

Selecting the mixing kernel

The mixing kernel is activated using the mixing keyword and specifying the mixing kernel and the corresponding parameters in the mixingKernel sub-dictionary:

mixing on;

mixingKernel
{
    mixingKernel IEM;
    Cphi         Cphi [ 0 0 0 0 0 0 0 ] 2.0;
    c            c [ 0 0 0 0 0 0 0 ] 1.0;
}

Integration of the sub-models

Sub-models are integrated using the realizable ODE solver implemented in general form into OpenQBMM. Settings for this solver are specified in the mixingProperties dictionary, as explained here.

Examples cases

An example case is provided in:

• OpenQBMM/tutorials/mixingTransportFoam/twoStreams/