Effect of acicular vortex generators on the aerodynamic features of a slender delta wing

Abstract This study investigates the flow structures and aerodynamic performance of a slender delta wing that has a sweep angle of 65 degrees and is equipped with acicular vortex generators. The results were compared with those of a smooth wing. Particle image velocimetry (PIV) was used to visualize the flow at six different sections of the delta wing in both the chord-wise and span-wise directions at an angle of attack (AOA) of 30 degrees and a Reynolds number of Re = 2.4 × 10 5 . The effect of the acicular vortex generators on the vortex diameters, locations of vortex breakdown, linear convolution integral patterns, circulation, and separation were studied. The Q-criterion was used for vortex boundaries for the span-wise sections. The results show the acicular vortex generators have positive effects on the aerodynamic performance of the wing. Furthermore, the acicular wing delays the vortex breakdown in comparison with a smooth wing and increases the flow momentum near the upper wing surface and behind the wing.

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