  A numerical investigation of the flow evolution over a pitching NACA 0012
airfoil incurring in deep dynamic stall phenomena is presented. The
experimental data at Reynolds number Re = 135 000 and reduced frequency k =
0.1, provided by Lee and Gerontakos, are compared to numerical simulations
using different turbulence models. After a preliminary space and time
convergence study, two- and three-dimensional URANS with different turbulence
models are explored, highlighting the advantages and the drawbacks. Then, the
turbulence-resolving capabilities of hybrid RANS/LES strategies are exploited
to recover and better represent the dynamic stall vortex. In detail,
Scale-Adaptive Simulations (SAS) and Stress-Blended Eddy Simulations (SBES) are
adopted. Furthermore, the LES resolved portion allows a spectral analysis of
the force and moment coefficients to investigate the contribution of frequency
lower than the pitching one. Finally, a comparison of the proposed approaches
with other numerical simulations is given.
