鸭式布局双旋稳定弹强迫运动理论研究

A Theoretical Study of Forced Motion for Dual-spin-stabilized Projectiles with Canards

为深入理解鸭式布局双旋稳定弹的动力学特性,对前体鸭舵周期性干扰引起的强迫运动进行了理论研究。建立一个简化七自由度飞行动力学模型,利用双旋稳定弹的横向运动方程组,在小攻角条件下推导出线性攻角运动模型,得到周期性舵控作用强迫项对应特解的具体表达式。通过对攻角快、慢圆运动角频率及强迫振幅变化特性在不同条件下的仿真分析,讨论该强迫运动的共振条件,分析舵面偏转角、舵面位置和极转动惯量比对共振幅值的影响。对大攻角条件下的前体转速闭锁问题进行初步分析,导出了该弹发生转速闭锁的稳定方位角及临界攻角表达式。

To provide a deep understanding of dynamic properties of dual-spin-stabilized projectile with canards,the forced motion induced by periodic disturbance of canards installed on the forward body is studied. A simplified seven degree-of-freedom rigid body dynamic model for this projectile is established.A linearized model of pitching and yawing motion is deduced by using the equations of transverse motion with the assumption of small angle of attack. The corresponding special solution of the forced term driven by periodic disturbance of canards is also obtained. The resonance conditions and influencing factors,such as canard deflection angle,canard placement,and ratio of axial moment of inertia,of this forced motion are discussed by analyzing the fast and slow arm turning rates of angle of attack and the forced amplitude numerically. The spin lock-in for the forward body is preliminarily analyzed under the condition of large angle of attack,and both the expressions of stable orientation angle and critical angle of attack for spin lock-in are proposed.