Active Flow Control Of Slender Body At Large Angle Of Attack

Phantom Yaw of modern high maneuverability aircraft caused by asymmetric vortices in forebody is investigated in this thesis.The experiments are conducted at a low-speed wind tunnel with a aircraft model of tangent ogive shape of a slender body. The regular of the side force changed with the roll angle and the angle of attack vary with a active flow control and the principle of lee-ward asymmetric vortices is studied by surface pressure measurement and dynamic force measurement.In order to determine the characteristics of forebody flow with the action of different type of perturbation, a systematic study of the lee-ward flow field over a slender body on the extreme high-angle-of-attack is conducted at a low-speed wind tunnel in Nanjing University of Aeronautics and Astronautics. By these wind tunnel testing we also recognize the concept of combination perturbation deeply.Effectiveness of the solution of Phantom Yaw by a active flow control with feedback with a swinging mini-nose-tip-strake technique for controlling forebody vortex asymmetry at high angles of attack is investigated. The system accepttion the signal of pressure sensor which monitor the variation of the pressure in lee-ward asymmetric vortices as a feedback signal control the mini-nose-tip-strake. These new solution was effective in suppressing side force to low level with only very small energy inputing.