某典型飞行器模型俯仰/滚转两自由度耦合动态气动特性

先进飞行器在大迎角高机动飞行过程中，气动力复杂演化与运动姿态剧烈变化的相互作用，容易诱发俯仰拉起的滚转或侧偏等耦合运动，呈现出十分强烈的多自由度动态气动力特性。为此，选取某典型四代机修型设计模型，利用FL-26风洞专用的俯仰/滚转两自由度动态试验装置，开展了单自由度和俯仰/滚转两自由度耦合运动的动态气动力特性研究。结果表明，研究模型在迎角30°左右会出现滚转单自由度的侧偏和小振幅摇滚运动现象；俯仰单自由度振动条件下，模型法向力和俯仰力矩会出现明显的气动迟滞特性；在强迫俯仰/自由滚转（或强迫滚转）两自由度耦合运动情况下，模型的侧偏运动幅值得到了一定的抑制，但纵横向气动力都出现了迟滞现象，甚至是多个气动迟滞环结构，容易引发耦合失稳发散。

Unsteady aerodynamic characteristics of two-degree-of-freedom pitch/roll coupled motion for a typical vehicle model

During high maneuvers at high angle of attack for advanced vehicles, coupled motions of pitch/roll or pitch/yaw may be induced by the interaction between the complex evolution of aerodynamic characteristics and the dramatic change of motion attitudes, displaying the strong multi-degree-of-freedom unsteady aerodynamic characteristics. Therefore, based on the dynamic test devices for two-degree-of-freedom pitch/roll in FL-26 wind tunnel, the unsteady aerodynamic characteristics of the one-degree-of-freedom motion and the two-degree-of-freedom pitch/roll coupled motion for a typical four-generation plane model are investigated. The results show that at around 30° angle of attack, the model occurs lateral deviation with for one-degree-of-freedom roll motion and wing rock of small amplitude. A significant dynamic hysteresis of normal force and pitch moment appears during one-degree-of-freedom pitch oscillation. During two-degree-of-freedom forced pitch/free roll coupled motion and forced pitch/forced-roll coupled motion, the amplitude of the sideslip angle decreases, but there are dynamic hysteresis with multiple hysteresis loops on longitudinal and lateral aerodynamic characteristics, which may induce instability and divergence.