推力作用下变质量柔性自旋飞行器稳定性分析

Stability Analysis of Variable-Mass Flexible Spinning Projectile under Thrust

针对变质量柔性自旋飞行器推力作用下稳定性问题,以Timoshenko梁为模型,考虑陀螺效应和剪切效应,基于有限元法建立系统振动方程,分析质量变化、推力作用和自旋转速对系统振动的影响,采用自适应Newmark法求解系统的振动响应。结果表明:质量和推力能够改变固有频率、进动频率和临界转速;受质量变化影响,自旋转速与临界转速相等时,飞行器发生短暂共振,共振响应峰值最大时刻与此重合时刻相比稍有延迟。

The stability of a variable-mass flexible spinning projectile under thrust is researched.The spinning projectile is simplified as a Timoshenko beam model,considering gyroscopic effect and shear effect,motion equations are derived based on the finite element method to analyze the effects of variable-mass,follower thrust and spinning speeds on the stability of the spinning projectile.Using the self-adaptive Newmark method,the transverse vibration response of the spinning projectile is solved.The results show that the variable-mass and thrust have influence on the natural frequency,precession frequency and critical speed.When the spinning speed is equal to the critical speed,the projectile occurs a transient resonance under the influence of the mass,and the peak time of the resonance response is slightly delayed compared with the coincidence time.