串联爆炸成型弹丸飞行气动特性的数值模拟研究

Numerical Simulation of Aerodynamic Characteristics of Double-layer Liners EFP

为了研究前后级爆炸成型弹丸(EFP)的姿态或位置相对变化对弹丸气动特性的影响,采用LS-DYNA数值模拟软件获得串联EFP,通过Pro/E软件实现串联EFP外形数据的传递。用计算流体力学软件CFD-FASTRAN对串联EFP进行了数值模拟,得到了前后级EFP分别存在不同攻角或相对偏移距离时的升力系数、阻力系数、静稳定储备量等气动参数。结果表明,当前级EFP存在攻角时,后级EFP流场分布呈不对称性;当后级EFP存在攻角时,对串联EFP气动特性影响较小;当前后级EFP存在偏移距离时,随着偏移距离的增大,后级EFP的阻力系数增大。

In order to study the influence of relative change of attitude or position between the two explosively-formed projectiles( EFPs) on the dynamic characteristics,the forming process of double-layer liners EFP is researched by LS-DYNA software. Pro/E software is used to reversely model the double-layer liners EFP for the realization of data transmission. The aerodynamic parameters,such as lift coefficient,drag coefficient and static stability,of double-layer liners EFP at different attack angles or relative offset distance are obtained by CFD-FASTRAN software. The results show that when the attack angle exists in the front EFP,the flow field distribution of the back EFP tends to be asymmetric; when the attack angle exists in the back EFP,it has little effect on the aerodynamic characteristics of the tandem EFP; and when the offset distance exists,the resistance coefficient of the back EFP increases with the increase in offset distance.