某大口径榴弹炮弹带挤进过程数值模拟研究

为探索某大口径榴弹炮发射条件下弹带挤进过程的力学机理，建立了弹带挤进坡膛的有限元模型。通过数值模拟研究弹带的动态挤进过程，分析弹带变形及刻槽形成过程，计算得到弹带动态挤进阻力、挤进压力和弹丸运动规律，给出了最大挤进阻力值、挤进压力值及对应时刻弹丸速度值。研究结果表明，挤进过程中弹带材料经历塑性变形流动，发生剪切失效占主导的韧性断裂并形成刻槽，弹带挤进后具有明显的层状特征，其内部区域的塑性变形量很小，弹带绝热变形产生的热量不足以使弹带材料熔化。文中采用的实验测试数据为数值模拟研究提供了支持，下一步工作的重点是开展针对弹带动态挤进阻力及弹丸运动规律的实验研究。

Numerical Research on Rotating Band Engraving Process of a Large-caliber Howitzer

A finite element model of the rotating band engraving into the forcing cone section of gun tube is established to explore the mechanism of engraving process of rotating band of a large-caliber howitzer under launch conditions. The dynamic engraving process of the rotating band is studied through numerical simulation, and the maximum resistance, engraving pressure and projectile velocity at the corresponding time are obtained. The deformation and groove formation processes of the rotating band are analyzed. The dynamic engraving resistance of the rotating band, the engraving pressure and movement of projectile are also calculated. The calculated results show that the rotating band undergoes plastic deformation and material flow, and forms the grooves on it due to ductile fracture, where shear failure is dominant. The rotating band has a layered feature after engraving, and the plastic strain in the band is small. The heat generated by adiabatic deformation of the rotating band is not enough to melt it. The simulation results of the deformation of the rotating band show good agreement with the test data from the recovered projectile.