Properties🔗

• Based on the k-ω-SST model
• Transition from laminar to turbulence
• Four-equation model
• Also known as the \(\gamma - Re_\theta\) model

Model equations🔗

Default model coefficients🔗

Initialisation🔗

See kOmegaSST initialisation

Boundary conditions🔗

Inlet

• Intermittency:

\[\gamma = 1\]

• Transition momentum thickness Reynolds number:

\[Re_\theta = \begin{cases} 1173.51 - 589.428 Tu + \frac{0.2196}{Tu^2} & \text{if } Tu \le 1.3 \\ \frac{331.5}{(Tu - 0.5658)^{0.671}} & \text{if } Tu > 1.3 \end{cases}\]

Where:

\[Tu = 100 \frac{\sqrt{2/3 k}}{|\u_\infty|}\]

Walls

• Intermittency: zero gradient

\[\frac{\partial}{\partial n} \gamma = 0\]

• Transition momentum thickness Reynolds number: zero gradient

\[\frac{\partial}{\partial n} Re_\theta = 0\]

Usage🔗

The model is specified using:

RAS
{
    turbulence      on;
    RASModel        kOmegaSSTLM;
}

Further information🔗

Source code:

• Foam::RASModels::kOmegaSSTLM

References

• Langtry and Menter [35]
• Menter et al. [50]
• Langtry [34]