Author(s)

Masayuki Anyoji¹, Shotaro Wakui¹, Daiki Hamada¹, Hikaru Aono²

¹Interdisciplinary Graduate School of Engineering Sciences, Kyushu University, Fukuoka, Japan.
²Department of Mechanical Engineering, Tokyo University of Science, Tokyo, Japan.

This study experimentally investigates aerodynamic characteristics and flow fields of a smooth owl-like airfoil without serrations and velvet structures. This biologically inspired airfoil design is intended to serve as the main-wing for low-Reynolds-number aircrafts such as micro air vehicles. Reynolds number dependency on aerodynamics is also evaluated at low Reynolds numbers. The results of the study show that the owl-like airfoil has high lift performance with a nonlinear lift increase due to the presence of a separation bubble on the suction side. A distinctive flow feature of the owl airfoil is a separation bubble on the pressure side at low angles of attack. The separation bubble switches location from the pressure side to the suction side as the angle of attack increases and is continuously present on the surface within a wide range of angles of attack. The Reynolds number dependency on the lift curves is insignificant, although differences in the drag curves are especially pronounced at high angles of attack. Eventually, we obtain the geometric feature of the owl-like airfoil to increase aerodynamic performance at low Reynolds numbers.

Owl Wing, Low Reynolds Number, Aerodynamics, Separation Bubble

Anyoji, M. , Wakui, S. , Hamada, D. and Aono, H. (2018) Experimental Study of Owl-Like Airfoil Aerodynamics at Low Reynolds Numbers. Journal of Flow Control, Measurement & Visualization, 6, 185-197. doi: 10.4236/jfcmv.2018.63015.