旋转稳定弹的自转角加速度特性

A Property of Roll Acceleration for Spin-stabilized Projectiles

为了研究旋转稳定弹的自转角加速度特性,利用外弹道学中描述旋转稳定弹自转动力学的简化微分方程,结合质点弹道方程,推导出自转角加速度一阶导数及二阶导数表达式。通过理论分析及对几种典型旋转稳定弹的计算,结果表明,在弹道降弧段上,当旋转稳定弹的结构参数、气动参数及飞行状态参数满足一定关系时,存在自转角加速度一阶导数为零的条件,此时自转角加速度在弹道降弧段上出现极值点;对于绝大多数情形,当弹丸的射角较小时(如小于20°),自转角加速度在降弧段上不存在极值点。

To study the characteristics of rotation angular acceleration for spin-stabilized projectiles,based on the simplified differential equation which describing the rolling motion and mass-point ballistics equation in exterior ballistics,the expressions of the first and the second derivatives of the rotation angular acceleration were derived.The ballistics characteristics of several typical spin-stabilized projectiles were analyzed and calculated.The results show that the conditions for the first derivatives of the roll acceleration becoming zero can be satisfied in the descending trajectory under the certain parameter combination of aerodynamics,flight status and the configuration parameters of the projectile.Meanwhile,the extreme point of the rotation angular acceleration curve appears at this point.For most cases,there is no extreme point for the roll acceleration curve on the descending trajectory when the elevation angle of the projectile is relatively small(e.g.,less than 20°).