The Research And Application Of Aerodynamic Characteristics Of Free-wing

Free-wing is a special wing between fixed wing and rotor, represented the original concept ofaircraft design. Which is free to pivot about a span-wise axis and like a weather vane as itautomatically adjust to sudden gusts or other change in the relative angle of attack. It won’t stall. Theresults indicated that the free-wing can keep a constant angle of attack which can also be controlled bydeflecting aileron during the flight. The combination of free-wing and fixed-wing improves the wingmaximum lift coefficient rapidly which reduces the take-off speed, and it effectively adjusts the wing’slift-to-drag ratio. The kind of wing may be promising in the small UAV platform with short takeoffand landing (STOL) capability and in increasing the cruise efficiency.As one of the most important characters, research the aerodynamic character and designprinciples. Explore the aerodynamic character by CFD and EFD. Get the control of the a constantangle of attack and feature of STOL.Started with the research airfoil of free-wing by CFD, Analysis and put forward to aerodynamiccharacteristics of the liberal wing of arc reflexed airfoil, with characteristic of stability. Comparativeand analysis several typical flow field in arc state reflexed airfoil.Choose the airfoil of GOE741.Design and make a free-wing model. Study the effects of streamvelocity, deflecting aileron, shaft position and shaft damping degree of freedom wing aerodynamiccharacteristics, the principle of freedom of access to the balance and equilibrium angle of attack of thewing control laws by EFD.Based on the aerodynamic character and design principles of free-wing, study the aerodynamiccharacteristics of free-wing and fixed wing. Research the aerodynamic characteristics of free-wingwith ground effect. And analyze the STOL characteristics of free-wing-UAV.Finally, design and make a free-wing-UAV. Research and estimate the aerodynamiccharacteristics and control characteristics of the free-wing-UAV. Take off the aircraft at theplayground. And test the STOL and flight characteristics of the free-wing-UAV. Make the technicalfoundation for further research and application.