弹体侵彻混凝土的三维数值模拟研究

随着技术的发展,弹体侵彻速度已经由低速侵彻(侵彻速度<900 m/s)向高速侵彻(1 200 m/s<侵彻速度<1 700 m/s)发展. 这将导致弹体的侵彻性能发生本质性变化,严重影响弹体在混凝土中的运动轨迹,甚至会导致弹体的破坏与失效. 侵彻过程中弹体所受到的压力极高,并且会产生大变形,对该过程进行全物理场的数值模拟需要处理大变形、多物质界面以及各类强间断的问题. 针对三维冲击问题数值模拟的困难,课题组设计了三维爆炸与冲击问题高性能仿真软件(Explosion-3D). 采用该软件对弹体高速侵彻混凝土进行数值模拟研究,弹体材料选用普通的45#钢,研究其在高速侵彻下的弹体形状的变化情况,采用对混合网格的处理来描述弹体的磨损. 数值模拟结果表明,对于45#钢这类普通材料,当其高速(1 400 m/s)侵彻混凝土时,弹体头部将出现严重变化且侵彻深度急剧下降.

Three Dimensional Numerical Simulation on Projectile Penetrating Concrete

The projectile penetration has been transformed from low speed penetration (<900 m/s) to the high speed penetration (1 200~1 700 m/s) with the development of technology. This transformation will significantly affect the ballistic instability and could lead to the destruction and the failure of the projectile. The process of projectile penetrating concrete involves high pressure, high strain rate, large deformation and other extreme conditions. The three-dimensional numerical simulation of the projectile penetration concrete needs to deal with the problems of large deformation, multi-materials and all kinds of strong discontinuity. To solve the numerical simulation difficulty of three-dimensional impact problem, the Euler type parallel algorithm was proposed and the high performance simulation software was designed of three-dimensional explosion and impact problem (Explosion-3D). The shape of projectile penetrating concrete at high speed was studied with the software using 45# steel as the material of projectile and the projectile of wear and tear was described by dealing the mixed grid. The simulation results show that the mass of projectile head will change seriously and the penetration depth will decrease for the ordinary materials such as 45# steel.