Effects of control parameters of three-point initiation on the formation of an explosively formed projectile with fins
The effects of the initiation diameter and synchronicity error on the formation of fins and stable-flight velocity of an explosively formed projectile (EFP) with three-point initiation are investigated. The pressure and area of the Mach wave acting on the metal liner at different initiation diameters are calculated employing the Whitham method. LS-DYNA software is used to investigate the asymmetric collision of detonation waves resulting from three-point initiation synchronicity error, the distortion characteristics of the liner resulting from the composite detonation waves, and the performance parameters of the EFP with fins. Results indicate that deviations of the Y-shaped high-pressure zone and central ultrahigh-pressure zone from the liner center can be attributed to the error of three-point initiation, which leads to the irregular formation of EFP fins. It is noted that the area of the Mach wave decreases, but the pressure of the Mach wave and the final speed and length-to-diameter (L/D) ratio of the EFP increase, benefiting the formation of the EFP fins, as the initiation diameter increases.
KeywordsThree-point initiation Initiation synchronicity error Initiation diameter Explosively formed projectile with fins
The work presented in this paper has been funded by the National Natural Science Foundation of China under NO. 11202103 and Qing-lan Project of Jiangsu Province.
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