Reynolds Stress Turbulence Modelling with γ Transition Model

Implementation of the SSG/LRR-ω-γ model is carried out in the current study to predict transition to turbulence. The framework uses a Reynolds stress transport model, SSG/LRR-ω, as the base turbulence formulation and is coupled with Menter's γ transition model. To extend its applicability to different transition mechanisms, the production terms in the Reynolds stress and specific dissipation rate transport equations are modified. SSG/LRR-ω-γ uses simplified correlations that do not depend on freestream quantities, making it coordinate independent and rendering it Galilean invariant. Additionally, using a second-order closure turbulence model makes it suitable for complex flow fields. The influence of different grid parameters on the model is also discussed. A validation study is performed using multiple benchmark flat plate cases as well as 2D and 3D geometries to demonstrate the model's capability in predicting different transition mechanisms. When compared to state-of-the-art transition models, the proposed model shows equivalent or higher predictive capability.