The Drag of an Elliptical Airfoil at a Reynolds Number of 1000


  • Sheila Tobing Faculty of Engineering, University of Indonesia, UI Depok Campus, Depok 16424, Indonesia



Elliptical airfoil, bumblebee kinematics, counter-rotating vortices


There have been many studies on the mechanisms of unsteady aerodynamics, such as leading-edge vortex (LEV) formation, wing-wake interaction, and spanwise flow. Spanwise flow can only be observed on three-dimensional wing models; however other phenomena such as LEV and wing-wake interaction can be captured using two-dimensional airfoil models. This study focuses on two-dimensional elliptical airfoil because this profile can generate counter-rotating vortices used by insects to generate aerodynamic forces. This research aims to analyze the drag production of two-dimensional elliptical airfoils flapping with bumblebee-inspired kinematics in asymmetrical normal-hovering mode at a typical Reynolds number range of . It is found that drag is generated during the downstroke while thrust during the upstroke. It is also found that the creation and shedding of counter-rotating vortices are closely related to the generation of thrust. The results also indicate that asymmetrical strokes can be used in normal hovering to minimize drag or produce thrust.

Author Biography

Sheila Tobing, Faculty of Engineering, University of Indonesia, UI Depok Campus, Depok 16424, Indonesia


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How to Cite

Tobing, S. (2022). The Drag of an Elliptical Airfoil at a Reynolds Number of 1000. CFD Letters, 14(5), 16–23.