飞翼布局飞机是现代先进飞行器设计的重要构型之一。由于缺乏平尾、垂尾等传统舵面，飞翼布局飞机在大攻角状态面临滚转、滚转与俯仰耦合、滚转与偏航耦合等失稳问题，严重影响飞机气动性能及飞行安全。对此开展了合成射流主动控制研究，提出了通过增强前缘涡进而改善动态稳定性的控制策略，分析了合成射流对飞翼布局滚转及其耦合运动的控制规律，揭示了飞翼布局飞机动态运动及耦合效应对合成射流控制效果的影响机理。研究结果表明，布置于飞翼布局飞机机翼前缘的合成射流可以有效增强前缘涡，进而改变气动力及力矩，特别是采用与滚转运动角速度方向相反的控制力矩策略能够增加滚转阻尼，改善横向稳定性。本文结果可为飞翼布局飞机增稳控制提供重要的技术支撑。
Flying-wing aircraft is an important configuration for modern aircraft design. Due to the lack of traditional control surfaces such as horizontal tails and vertical tails, the flying-wing aircraft may encounter a serious of dynamic problems at high angles of attack, such as roll instability, coupled pitch-roll instability, and coupled yaw-roll instability, affecting the aerodynamic performance and flight safety. To address this issue, this study of synthetic jet active flow control is conducted. The control strategy of enhancing leading-edge vortex to improve stability is proposed. The effect of the synthetic jet on the control law of the roll motion and its coupled motion is analyzed, and the flow control mechanism of the synthetic jet under dynamic motion and the coupled effect revealed. It is indicated that the synthetic jet positioned at the leading edge of the flying-wing aircraft can effectively enhance the leading-edge vortex, thereby changing the aerodynamic force and moment. A control strategy is proposed to ensure that the control moment vector is always opposite to the angular velocity of the roll motion, which can increase the roll damping, thereby improving the lateral stability. The present results can provide an important technical support for the stabilization control of the flying-wing aircraft.
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