2015 年 63 巻 5 号 p. 217-224
For the investigation of UAV and MAV, development of wing section which has high aerodynamics performance at the low Reynolds numbers region is required. In addition, the aerodynamic characteristics of the airfoil are influenced by the flow separation which is affected by the wing section configuration. In this study, the influences of upper surface configuration on the aerodynamic characteristics of the Ishii airfoil at the Reynolds number of 50,000 are experimentally investigated. The results demonstrated the laminar separation near the trailing edge whose configuration was resembled to that of NACA0012 airfoil. The lift coefficients, which becomes negative values in the NACA0012 airfoil case because of the laminar separation at the trailing edge, increases almost liner with the increase in the angle of attack. Turbulent region which is increased by the formation of the laminar separation bubble near the leading edge increases drag coefficients. The desirable upper surface configuration of wing section maintains the re-attachment of the laminar separated flow near the trailing edge at high angle of attack condition.