The intermittency multiplies the production term in the equation for the turbulent kinetic energy:

This is the only modification to the underlying turbulence model. The new transition model is compatible with k-ω based turbulence models.

The intermittency is computed from an algebraic formula. The full model formulation will be published shortly and only the essential elements of the formulation are given here. The underlying concept is that transition is triggered by a correlation which contains the major physical effects. The critical displacement thickness Reynolds number is termed and contains the correlation which fits the experimental transition locations. is a function of the turbulence intensity and the non-dimensional pressure gradient parameter . Both are computed locally in the same way as in the existing one-equation -model (Intermittency Transition Model in the Fluent Theory Guide):

(4–199)

(4–200)

For numerical robustness, is bounded as follows:

(4–201)

As inherent to the LCTM concept, the formulation is based on the ratio between the actual state of the boundary layer described by the vorticity Reynolds number and the critical Reynolds number :

(4–202)

(4–203)

(4–204)

The intermittency is then computed from:

(4–205)

The quantity is defined as with the strain rate , the vorticity rate , and the from the -equation of the underlying turbulence model.