SST k-omega model
The SST k-omega turbulence model [Menter 1994] is a two-equation eddy-viscosity model which has become very popular. The SST formulation combines the best of two worlds. The use of a k-omega formulation in the inner parts of the boundary layer makes the model directly usable all the way down to the wall through the visous sub-layer, hence the SST k-omega model can be used as a Low-Re turbulence model without any extra damping functions. The SST formulation also switches to a k-epsilon behaviour in the free-stream and thereby avoids the common k-omega problem that the model is too sensitive to the inlet free-stream turbulence properties. Authors who use the SST k-omega model often merit it for its good behaviour in adverse pressure gradients and separating flow. The SST k-omega model does produce a bit too large turbulence levels in regions with large normal strain, like stagnation regions and regions with strong acceleration. This tendency is much less pronounced than with a normal k-epsilon model though.
Kinematic Eddy Viscosity
Turbulence Kinetic Energy
Specific Dissipation Rate
Closure Coefficients and Auxilary Relations
- Menter, F.R. (1994), "Two-equation eddy-viscosity turbulence models for engineering applications", AIAA Journal, vol. 32, pp. 269-289.