Assessment of turbulence models for the simulation of turbulent flows past bluff bodies

• Scale-resolving models can predict complex turbulent flows.
• Scale-resolving models perform better than regular URANS turbulence models.
• One-Equation-SAS and the k-ω-SST–SAS models reduce the eddy viscosity levels to operate in Scale-Resolving mode.

The accuracy of a recently developed one-equation turbulence model in predicting complex flows with massive separation is assessed against the well-known Spalart Allmaras (SA) and the k-ω-SST-Scale Adaptive Simulation (SAS) models. The unsteady 3-D flow past a square cylinder at Re=2.2×104, as well as a 3-D flow over a wall-mounted cube at Re=4.0×104 are computed and compared to available experimental data. The recently developed model is capable of resolving turbulent flow structures, thereby predicting all major unsteady phenomena with a marked improvement over other Reynolds average Navier–Stokes (RANS) models. The computational time required by the model in comparison to that required by Large Eddy Simulation (LES) renders it a suitable candidate for simulating 3D unsteady complex engineering flows such as building aerodynamics with reasonable accuracy.