Scale effect during the dynamic stall of dynamic airfoil

Studying the scale effect of dynamic airfoil is helpful for understanding stall phenomenon and unsteady wall interference. In this paper, characteristics National Advisory Committee Aeronautics 0012 was studied using time-resolved pressure measurements first time, which different from Reynolds number as experimental not varied. The evolution field vortex development on scaled models investigated. Significant effects were observed during its stall. With model increases c = 500 to 900 mm, shear layer secondary separation observed, indicating that vortices suction surface enriched. Furthermore, vortex-induced occurrence time significantly affected. varied Cp ≈ −4.25 −1.5. structure angle attack delayed by Δα 0.5°. Further analyses showed are attributed flow transition interference interactions. Thus, two physical quantities, Sm Sw, innovatively defined associate complexity, scale, wind tunnel pressure. This study helps deepen provides guidance correction.