Abstract

In the low-Reynolds-number range below Re = 60,000, SD7003 and Ishii airfoils are known as high-performance low-Reynolds-number airfoils with a relatively high lift-to-drag ratios. Although the aerodynamic characteristics at particular Reynolds numbers have been thoroughly studied, research is lacking on how Reynolds numbers affect the aerodynamic characteristics that become pronounced for general low-Reynolds-number airfoils. This study investigates the Reynolds number dependence on the aerodynamic performance of these two airfoils. The results demonstrate that the Ishii airfoil is particularly less dependent on the Reynolds number of the lift curve compared to the SD7003 airfoil. Although there is a slight difference in the high angles of attack above the maximum lift coefficient, the lift slope hardly changes, even when the Reynolds number varies.

Keywords

low-reynolds-number, aerodynamics, reynolds number dependence, separation bubble, ishii airfoil