Effect of wing-tip vortices on turbulent boundary layer and wake of a NACA0012 wing*

Wing-tip vortices are formed at the tip of the finite-span lift-generating surfaces due to pressure difference between the suction and pressure sides. The current study aims at investigating, from a fundamental point of view, the effect of these wing-tip vortices on the turbulent boundary layer (TBL) and wake of a NACA0012 wing at a chord-based Reynolds number of 200,000 and at different angles of attack up to 10 degrees. This includes the effect of the imposed spanwise pressure gradient, velocity and rotation on the TBLs (specially on the suction side), the impact of the wing-tip vortices on the wake development and relaminarization due to imposed rigid-body rotation, the impact on the overall drag, and a number of additional flow quantities. The study is complemented by a direct comparison to infinite-span (periodic) wings at the same configurations, to allow for a better understanding of the effect of three dimensionality. Our numerical experiments take advantage of the AMR-capable (adaptive mesh refinement) version of the high-order code Nek5000 to perform a set of high-resolution large-eddy simulations (LES). The results are analyzed in terms of flow statistics, budgets, and energy spectra.