Pattern recognition of the flow around a pitching NACA 0012 airfoil in dynamic stall conditions

Pattern recognition of the flow around a pitching NACA 0012 airfoil in dynamic stall conditions

Giacomo Baldan, Alberto Guardone

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Abstract. The present work numerically investigates the flow evolution of a pitching NACA 0012 airfoil incurring in deep dynamic stall phenomena. The experimental data at Reynolds number Re = 1.35 · 105 and reduced frequency k = 0.1, provided by Lee et al., are compared to numerical simulation using different methods. Firstly, 2D URANS with different turbulence models are explored highlighting the advantages and the drawbacks of each strategy. On the one hand, simulations are able to describe most characteristic flow features of dynamic stall. On the other hand, numerical models still struggle in describing the inherent complexity of instability and transition from laminar to turbulence, resulting in a misprediction of the angle of attack at which the dynamic stall vortex (DSV) is generated and convected rearward. Finally, a Proper Orthogonal Decomposition (POD) is proposed to analyze the main flow features and to recognize flow patterns. The decomposition of both velocity magnitude and pressure fields shows a high frequency content requiring a large portion of the modes to recover most of the flow energy.

Dynamic Stall, Proper Orthogonal Decomposition, Pitching Airfoil, Pattern Recognition, Helicopters, Wind Turbines

Published online 11/1/2023, 5 pages
Copyright © 2023 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA

Citation: Giacomo Baldan, Alberto Guardone, Pattern recognition of the flow around a pitching NACA 0012 airfoil in dynamic stall conditions, Materials Research Proceedings, Vol. 37, pp 161-165, 2023


The article was published as article 35 of the book Aeronautics and Astronautics

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