Revisiting the Turbulent Scale Equation

The paper revisits two-equation turbulence models with an emphasis on the turbulent length scale equation. Rotta's derivation of the kL model is re-evaluated and some of the assumptions made during the original for- mulation of the kL model will be relaxed. As a result, the second deriva- tive of the velocity field appears in the length scale equation instead of the third derivative as in the original model. First results, including as- pects of Scale-Adaptive Simulation (SAS) capabilities of the new model formulation will be presented.