Coupling Two Correlation-Based Transition Models To The K-KL Eddy Viscosity Turbulence Model

When dealing with flows at moderate Reynolds numbers, the laminar and transition regions are a key component of the flow solution. In applications such as wind turbines and unmanned aerial vehicles, an accurate prediction of the aerodynamic forces requires accounting for these effects. In Reynolds-averaged Navier-Stokes simulations, this is done by incorporating transition models because commonly used turbulence models are unable to predict a significant extent of laminar flow. In this paper, we present and study the coupling of the local correlation-based gamma -Re theta and gamma transition models with the k-kL (KSKL) turbulence model, and we compare it to the original formulation using the k-omega shear-stress transport (SST) turbulence model. The coupling of the models is calibrated for the flow over a flat plate and subsequently tested for the flow around the S809 and NLF(1)-0416 airfoils, as well as around a 6:1 prolate spheroid. The results show that the combination of the gamma -Re theta transition model with the KSKL turbulence model leads to a reduction of the numerical uncertainty (discretization errors) when compared to its application with the SST model. On the other hand, the combination of the KSKL model with the gamma transition model leads to the sharpest transition of the four combinations tested.