Experimental Study for IK Airfoil at Low Speed in a Rectangular Air Cross Flow

The airfoil design problem has played an important role since the man first expressed the desire to fly till now so as to adapt man’s air plane application with a good aerodynamic performance requirements, including lift, drag and pitching moment in a specified Mach/ Reynold number flow regime as well as geometric constraints. Therefore, it would always be desirable to design an airfoil with the ability to adapt to its current flow conditions and alter its shape to keep it efficient at any speed. This work, based on designing and experimental investigation the ability of the new (IK) airfoil design to work in a wide range of subsonic speeds. The (IK)airfoil cord length 157mm,span length 300mm, maximum thickness 10.32. The experiment covers the following ranges :Reynolds number 152908-305816 and angle of attack (-6°, -3°, 0°, 3°, 6°, 9°, 12°, 15°, 18°, 21°, 24° and 33°). Results showed that as speed increases lift coefficient increases to reach a max value (10.227) at Reynold number 264844 and attack angle (30°). The ratio of lift to drag coefficient (CL/CD) reaches its max value with the same Reynold number, but at an attack angle equals to (3°) where it reaches (10.0857), beyond this threshold (C L) and (CL/CD) will start to decrease as speed increase.