Implicit rule for the application of the 2-parameters RANS turbulence models to solve flow problems around wind turbine rotor profiles

Appropriate wind farm layout design depends on the accurate prediction of flow characteristics around turbine’s rotor, especially as it affects downstream turbines. The complexities of the flow characteristics as a result of the wake deficit affects prediction accuracy. Thus, the importance of selecting an appropriate turbulence model to resolve the flow dynamics of the wake deficit cannot be overemphasized. There are several numerical turbulence models and selecting one that converges to the flow characteristics is inevitable for accurate performance prediction. Most practices usually based the choice of model on previous studies’ methodologies and results without the essence of application. While selecting the best performing model is usually not straightforward, it is however hinged on knowledge of the capabilities to resolve eddies. This is the focus of this study. Various studies were analysed alongside their turbulence resolution techniques with special consideration given to the Reynolds- Averaged Navier Stokes methodology and the two equation transport models of k-ε and k-ω turbulence models. The study showcased and determined the rule of engagement for the application of the eddy viscosity model of the type of the k-ε and k-ω turbulence models to resolve the closure problem associated with flow analysis. The shortcomings of each model were analysed and the comparative advantage of each was showcased alongside the combinatorial shear stress transport k-ω model