综合考虑飞行动力学和气动弹性力学的相互影响,基于结构弹性模态和刚体飞行模态,耦合求解非定常气动力和结构动力学模型,研究大长细比导弹受弹性变形影响时的纵向稳定性。研究发现,大长细比导弹的弹性特征明显,结构弹性变形和刚体运动之间的相互影响不容忽视,分析大长细比导弹稳定性时需要将结构弹性变形与刚体运动统一起来进行研究。考虑刚体俯仰模态后,导弹的稳定性发生显著变化,系统由稳定变为不稳定,在较低动压下系统失稳,主要表现为俯仰模态的静失稳发散。来流动压和结构刚度会影响大长细比导弹的纵向稳定性。

Considering interaction between flight dynamics and aeroelasticity, the influence of elastic deformation on longitudinal stability of a slender missile was analyzed by solving the unsteady aerodynamic flow and structural motion equations, based on the structure elastic mode and rigid flight mode. It was shown that, for the flexible missile with high slenderness ratio, influence between structural elastic deformation and rigid motion shall not be ignored. The stability analysis of the slender missile needed considering the structural elastic deformation and rigid flight motion together. After considering the pitching mode of the rigid body, the stability of missile was significantly changed. System stability changed from stable to unstable, and mainly presented longitudinal static instability of the pitch mode. Dynamic pressure and structural stiffness would affect the longitudinal stability of the missile.