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arXiv · 2405.12036

Wall-resolved large eddy simulations of a pitching airfoil incurring in deep dynamic stall

Giacomo Baldan·Alberto Guardone
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Abstract

This study investigates the flow evolution around a sinusoidal pitching NACA 0012 airfoil, defined by the National Advisory Committee for Aeronautics (NACA), undergoing deep dynamic stall using a wall-resolved large eddy simulation (LES) approach. Numerical results are assessed against experimental data from Lee and Gerontakos (2004) at Reynolds number Re = 135 000 and reduced frequency k = 0.1. A comprehensive analysis of the computational model span size is presented, highlighting the requirement for a span-to-chord ratio of at least one to correctly capture the dynamic stall vortex physics in the downstroke phase. Furthermore, a comparative assessment with state-of-the-art Reynolds-Averaged Navier-Stokes (RANS), hybrid RANS/LES, and the experimental data is carried out. All the numerical models concur to the same flow behavior and exhibit similar differences with the experiments.

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Giacomo Baldan, Alberto Guardone. 2024-05-20. Wall-resolved large eddy simulations of a pitching airfoil incurring in deep dynamic stall. https://doi.org/10.1063/5.0252828

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