泡沫铝防护屏的Whipple防护结构弹道极限数值模拟研究

为研究泡沫铝板作为防护屏的Whipple防护结构抵御空间碎片超高速撞击的特性,模仿泡沫金属的生产原理建立了泡沫金属细观结构几何模型,结合自编的光滑质点流体动力学程序进行了超高速撞击数值仿真,通过与实验对比验证了模型的有效性.分别对相对密度为23.2%的理想均匀和非均匀开孔泡沫铝板作为防护屏的Whipple防护结构进行了数值仿真,得到了它们的弹道极限曲线,并与实心铝板作为防护屏的Whipple防护结构进行了对比分析.结果表明,相同面密度的泡沫铝板相对于实心铝板能够在更低的速度上将弹丸粉碎、液化及气化.泡沫铝板作为防护屏,在总体上拥有更好的防护性能;相同面密度的理想均匀泡沫铝板的防护性能总体上优于非均匀泡沫铝板.

Numerical simulation investigation in ballistic limit of Whipple shield structure with Al-foam bumperb

In order to research the characteristic of Whipple shield subjected to hypervelocity impact of space debris using Al-foam plate as bumper,a microstructure model of geometry for metallic foams was set up simulating their manufacturing process.Hypervelocity impact numerical simulations were conducted by self-programmed Smooth Particle Hydrodynamics and the model is validated by comparison with experimental results.The ballistic limit curves of Whipple shields were obtained numerically using uniform and non-uniform opencell Al-foam plate as bumper respectively.The relative density of foams is 23.2% and their ballistic limit curves were compared with that of Whipple shield with solid Al-plate bumper.The results indicated that Alfoam can fragmentate,liquefy or even gasify projectile at lower velocities than Al-plate under the same areal density.Al-foam bumpers have better shield performance than Al-plate as a whole.The shield performance of uniform Al-foam bumper is better than that of non-uniform one on the whole under the same areal density.