旋转弹丸外弹道自转角速度衰减规律半经验公式

为了得出简单、直观而又比较准确的旋转弹丸外弹道自转角速度衰减规律计算公式，根据弹丸结构特性对柔格里半经验公式进行了简化，由此得到了指数形式的半经验公式，又根据弹丸弹带刻槽后所形成的空气动力阻力矩大于弹丸表面摩擦力矩的实际，经分析和简化又得到了幂函数形式的半经验公式。利用所能搜集到的中外弹丸转速测试结果，给出了这两种半经验公式中的系数数值。数值算例表明，这两种半经验公式不但所需计算参数少，而且准确度也高于柔格里公式，可以满足弹丸与引信的工程设计、性能估算和分析论证要求。

Half-Experiential Formulas for Calculating Decreasing Angular Velocity of Projectile in Trajectory

In order to get simple formulas for accurately calculating decreasing process of projectile's angular velocity in trajector,the Roggla half experiential formula is simplified in accordance with specific property of projectile structure. Consequently, a half experiential formula in exponential form is gotten.Then by the fact that air dynamic resistance moment which is formed by carving groove on driving band is greater than frictional moment on projectile surface, another half experiential formula in power function form is gotten after analyzing and simplifying.By using all collectable domestic and foreign measuring results of decreasing angular velocity of spinning projectile in trajectory,the coefficient values in above mentioned two kinds of half experiential formula are gotton. Volume calculations show that not only the two kinds of half experiential formula need not more parameter, but also the calucating accuracy when using the two experiential formula is higher than that when using the Roggla half experiential formula. They can satisfy demands of engineering designing, and performance estimating, analyzing and demonstrating for projectile and fuze.