为了为某舰炮弹丸弹底触发引信惯性前冲发火机构对海射击时的动态特性设计和评估提供参考,借助ANSYS/LS-DYNA软件,采用任意拉格朗日欧拉方法,仿真了该弹丸不同落速、不同落角的入水过程,得到不同落速、落角和是否自转等条件下的弹丸入水前冲过载。落速或落角越大,前冲过载越大、过载峰值宽度越小;小落角入水过程中弹丸姿态不稳定,易发生跳弹,使前冲过载减小,甚至消失,并产生较大径向过载;自转对该弹丸入水前冲过载影响较小,可忽略;落速250m/s、落角5°时的过载是引信惯性发火机构发火准确性设计要考虑的可信极限弹道环境,前冲过载峰值约为287g,持续时间约为1ms。

In order to design and evaluate the fuze's inertial forward firing mechanism of a medium caliber naval shell when shooting at sea, with the help of the commercial software ANSYS/LS-DYNA, using the arbitrary Lagrangian-Eulerian method, the water entry process of projectile with different falling speed and different falling angles was simulated. The water entry set forward overload coefficient of the projectile under the conditions of different falling speed, angle and rotation were got. The greater the falling speed or the falling angle, the greater the set forward overload, the smaller the overload peak width. The attitude of projectile was unstable when it fell into the water with small angle, and ricochet easily occurred. The set forward overload of projectile was reduced or even disappeared, and larger radial overload was produced. Rotation of the projectile entering the water had little effect on set forward overload and it could be neglected. When the overload of fall velocity was 250 m/s, and the falling angle was 5 degrees, the confidence limiting ballistic environment for inertial firing mechanism of fuze which firing accuracy design must be considered, the peak value of set forward overload was about 287 g, and the duration was about 1 ms.