身管烧蚀磨损条件下弹体发射强度数值模拟

为研究身管烧蚀磨损对弹体发射强度的影响规律,建立了烧蚀磨损身管与弹丸的弹炮耦合有限元模型和内弹道数学模型。采用内弹道方程与弹炮耦合有限元模型双向求解算法对内弹道方程进行求解,试验与算例的对比结果验证了模型的正确性。以弹丸挤进时刻、最大膛压时刻、弹体与身管碰撞时刻的临界状态应力为表征量,分析了弹体发射强度随身管烧蚀磨损量的变化规律。结果表明,严重磨损工况相对于正常身管工况,前2个临界状态应力值分别降低了19.4%、12.5%,第3个临界状态应力增大了149.2%。由此可知,随着烧蚀磨损量增大,弹丸挤进时刻、最大膛压时刻的临界状态应力对发射强度影响度在降低,而弹丸与身管碰撞临界状态应力成为影响弹体结构发射强度的主要因素。

Numerical Simulation on Firing Intensity of Projectile Under the Conditions of Bore Erosion

To study the influence of bore erosion on projectile firing intensity,the coupled projectile-gun finite element model and mathematical model of interior ballistics were established. Commutative algorithm for interior ballistic equation and finite element model was used to solve interior ballistic model. The accuracy of the simulation model was verified by comparison of the experiment with example. The critical state stress of projectile at the moment of engraving,maximum chamber pressure and colliding with barrel were taken as characterization to analyze the firing intensity of projectile with wear of barrel. The calculated results show that by comparing the conditions of bore erosion with that of normal bore,the first two stress decreases by 19.4%and 12.5% with the increase of wear,but the third stress increases by 149.2%. With the increase of erosion amount,the impact of the critical state stress on the firing intensity at the time of projectile engraving and the maximum pressure decreases,and the critical state stress of the projectile colliding with the barrel is the main factor affecting the firing safety of the projectile structure.