Effect of eccentric initiation on the flight characteristics and ballistic dispersion of EFP
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摘要: 为研究起爆不对称性对EFP战斗部飞行特性的影响, 对不同偏心量下⌀60 mm弧锥结合罩EFP战斗部进行飞行弹道实验。实验结果表明:偏心起爆条件下, 当相对偏心量小于3.3%时, EFP在网靶穿孔接近圆形, 弹丸飞行稳定; 起爆相对偏心量达到6.7%时, 弹丸飞行过程中摆动幅值增大, 降低了对目标的打击精度和毁伤效果。利用LS-DYNA及CFX非线性动力学有限元程序对不同起爆偏心量下成型EFP的空气动力学特性进行数值模拟, 描述了偏心起爆影响EFP成型对称性, 改变弹丸在飞行过程中流场的分布特征, 从而导致弹丸飞行过程中无规则运动的全过程。Abstract: Flight trajectory experiments were conducted with⌀60 mm diameter EFP warhead in order to investigate the effect of eccentric initiation on the flight characteristics of EFP.The results indicate that the projectile flight stability with perforations nearly circular in the net target when eccentricity is less than 2 mm.The accuracy of strike is lower and terminal effects are less harmful because the projectile overturns during the flight, with the eccentric value of 4 mm.The forming of EFP and its flight characteristics with different eccentricity was numerically analyzed by using LS-DYNA and CFX.EFP is asymmetrical under the conditions of the eccentric initiation.It changes the symmetry of the flow field which leads to instability during flight.The research results provide a reference to detonation parameter of EFP warhead.
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表 1 不同工况气动力初始计算状态及基本参数
Table 1. The initial calculation state and basic parameters of different aerodynamic conditions
K/% v/(m·s-1) S/cm2 L/cm 0.0 1 500.08 3.02 4.31 3.3 1 496.89 3.53 4.14 5.0 1 487.00 6.37 3.95 6.7 1 475.08 9.15 3.73 -
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