内膛损伤枪管膛口扰动参数研究

为分析枪管内膛损伤导致射击精度下降、椭圆弹孔率上升进而导致枪管寿终的问题，基于系统的某12.7 mm机枪枪管寿命试验，建立无损伤枪管、寿命中前期枪管、寿命中期枪管及寿终枪管4个寿命阶段枪管内弹道过程的弹枪热力耦合模型。采用均匀设计方法安排弹药随机因素影响下的弹头内弹道过程仿真实验，获得不同内膛损伤程度的枪管膛口扰动状态随弹药参数变化的响应值，仿真计算结果与试验数据吻合较好。利用基于3次B样 条曲线的偏最小二乘回归建模方法对传统均匀设计响应面法进行改进，获得以弹药参数为自变量的弹头膛口扰动响应面方程及枪管在不同寿命阶段时弹药随机因素对弹头出膛时初始扰动状态的影响规律。仿真实验及数据分析结果表明：各弹药参数对不同寿命阶段的枪管膛口扰动量贡献度均不相同；为降低寿命末期枪管的弹头膛口扰动，应尽量减少弹头的质量偏心，在合理范围内适当减少弹头壳初始屈服应力，并取适中的弹头壳圆柱部直径和装药量。

Research on Muzzle Disturbances of Gun Barrel with Bore Damage during Firing

In order to explore the mechanism of how bore damage leads to the decrease in firing accuracy and the rise in the ratio of elliptical shot holes, eventually leading to the end of a barrel life, the thermo-mechanical coupling finite element analysis (FEA) models of barrels with bore damage at 4 life stages, including undamaged barrel, middle-early life barrel, mid-life barrel, and end-of-life barrel，are established based on barrel life tests. Uniform design method is used to design the simulation test of interior ballistics process influenced by random factors of ammunition. The response values of muzzle disturbances of differently damaged barrels were acquired in the simulation test. The simulated results are in well agreement with the experimental data. The response surface equation for muzzle disturbance for taking ammunition random factors as independent variable and the rules of how ammunition random factors influence the muzzle disturbances of differently damaged barrels are obtained by using the partial least-squares regression method based on cubic B-spline curve and the uniform design-response surface method. The simulated and analyzed results show that the contribution of each ammunition random factor to the muzzle disturbances of differently damaged barrels is unequal. In order to reduce the muzzle disturbances of barrels in its later lifetime, the mass eccentricity of bullet and the initial yield strength of jacket material should be decreased, and the cylindrical diameter and charge weight should be moderate. Key