锥形弹丸超高速撞击防护屏的碎片云特性参数研究

摘要

空间碎片在撞击航天器防护结构时会产生碎片云,而碎片云又将对航天器造成二次损伤,因此很有必要针对不同形状的空间碎片超高速撞击产生的二次碎片云特性进行研究.选取航空材料Al 2017-T4、Al 2A12作为弹丸和防护屏材料,采用非线性动力学分析软件AUTODYN-2D结合光滑质点流体动力学方法,对不同长径比的锥形弹丸分别以锥底和锥尖超高速正撞击单层防护屏薄板所产生的碎片云特性进行数值模拟,得到了碎片云的前端轴向速度、径向直径、轴向长度及穿孔直径等特性参数随弹丸撞击部位及长径比变化的规律.%Space debris of different shapes,when impacting spacecraft protection structures,may produce debris clouds which in turn cause secondary damage on the spacecraft.Therefore,it is of great necessity to investigate the characteristics of debris clouds formed from hypervelocity impact by space debris of diverse shapes.We selected 2 aerospace materials,Al 2017-T4 and Al 2A12,respectively as the impacting projectile and the spacecraft shield material,and performed numerical simulations utilizing the smoothened particle hydrodynamics (SPH) technique with the nonlinear dynamic analysis software AUTODYN-2D.We investigated numerically the characteristics of debris clouds,which were generated by the hypervelocity impact of conical projectiles with the same mass and striking velocity but different length-radius ratios normally on the single protective plate in the conical bottom and tip directions.The results show that the axial velocity of the tip particle,the radial diameter and the axial length of debris clouds,and the diameter of the perforation hole are affected by the length-radius ratio and the impact direction of conical projectiles,and their changing regularities are established in the present work.