الفهرس 
Introduction to Flow ControlOnly 14 pages are availabe for public view
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Abstract
Controlling of the airfoil flow separations is becoming increasingly important from both fundamental and industrial points of view due to recent developments in wind turbines, small unmanned aerial vehicles and micro air vehicles. The present thesis concerns the effect of using the Humpback Whale-like leading edge tubercles on the heavily Cambered Selig1223 airfoil to improve the aerodynamic Performance and delay the stall angle of attack. The Selig1223 profile is commonly used in many aerodynamic applications and especially in the high lifting capacity UAVs in the SAE-Aero-Design Competition. The investigation is based on numerical simulation of the flow characteristics around the Selig 1223airfoil. The Amplitude of each tubercle changes from (0.01C, 0.025C, 0.045C) where C is the airfoil chord. The span wise distance between the centerlines of two adjacent tubercles changes from (0.05C, 0.125C, 0.25C). A wide range of angle of attack was tested; from 0˚to 20˚. The value of Reynolds number is 250,000 which is a realistic value for these types of UAVs. The Realizable k- ω Turbulence model was used in the investigation. The numerical scheme was validated using the experimental results of the standard Selig1223 profile (without tubercles). The results cover lift and drag coefficients variation with angle of attack and also visualize the delaying of boundary layer separation using the Time-averaged velocity contours. The investigation shows a remarkable improve in the lift to drag ratio at AOA=6 of airfoil tubercles with Amplitude =0.045C and wavelength=0.05C with an increase by 17.14 % compared to the maximum ratio of the regular airfoil at AOA=4. After AOA=9 nearby all tubercle configuration shows less performance compared to the regular airfoil.