Abstract:
To explore the control capability of dual synthetic jets (DSJ) on the heading attitude of flight vehciles, numerical simulations were carried out to study the aerodynamic characteristics and control mechanism of reverse DSJ actuators on the airfoil flow field at both small and large angles of attack. Meanwhile, flight tests were also implemented to verify its control ability of the heading attitudes. The results show that at a small angle of attack, the reverse DSJ can increase the drag and decrease the lift slightly, while the pitching moment basically remains unchanged. At a large angle of attack, however, the lift, drag, and nose-down pitching moment can be increased by the reverse DSJ. At a small angle of attack, high-pressure zones and low-pressure recirculation zones are formed before and after the actuator exits due to the resistant effect of the jet, which causes the increase of the pressure difference induced drag. As the pressure envelope remains basically unchanged, the lift variation is negligible. At a large angle of attack, in addition to the formation of high-pressure and low-pressure zones before and after the jet exits, flow separation in the leeward side of the airfoil occurs in advance, enlarging the flow separation, reducing the pressure inside the separation region and augmenting the area of pressure envelope, which leads to the increase of both the lift and drag forces. Results of the flight tests show that the reverse DSJ can achieve an effective control of the heading attitude during the cruising flight, with a maximum yaw angular velocity of 9.01°/s.