Wind tunnel virtual flight test of flying wing configuration with active flow control

Flying wing configuration aircraft pursues excellent aerodynamic and stealth performance. However, traditional mechanical control surfaces can compromise its stealth profile and may lead to a decrease in control effectiveness at moderate angles of attack, potentially causing aircraft instability and loss of control. Active Flow Control (AFC) techniques effectively address the aforementioned drawbacks. In this study, a wind tunnel virtual flight test system, integrated with closed-loop active flow control, is constructed. The system is capable of simulating active flight attitude control of controlled model under both steady and unsteady incoming flow conditions. Utilizing this system, wind tunnel virtual flight tests of the flying wing configuration model with AFC are conducted, obtaining its three-axis attitude control characteristics under steady flow conditions. Results demonstrate that consistent and controlled pitch and roll moments can be generated through trailing edge circulation control, while required yaw moment can be generated through wingtip reverse jets, achieving stable three-axis attitude control of the flying wing aircraft. Particularly, when controlling longitudinal attitude of the model with pitch circulation control, the generated pitch moment is linearly correlated with jet momentum coefficient. Furthermore, a closed-loop control strategy for gust load alleviation based on model longitudinal attitude feedback is proposed. The stability enhancement ability of AFC for flying wing configuration model under gust disturbance is validated. Additionally, it is further discovered that the effectiveness of the stability enhancement control is jointly determined by the intensity of the jet applied for control and the phase relationship between the control signal and the gust disturbance.