Research on the Penetration Characteristics of Rod-shaped EFP and Its Influencing Factors

doi:10.12382/bgxb.2024.0682

Abstract

Abstract:

For the penetration efficiency of rod-shaped explosively formed penetrator (EFP), the numerical simulation method is used to study the penetration characteristics of rod-shaped EFP. The influences of forming shape, impact velocity, and material characteristics of rod-shaped EFP on its penetration ability are analyzed, and the influence law of rod-shaped EFP forming characteristic parameters on the penetration process is obtained. The research results indicate that the rod-shaped EFP maintains a constant velocity motion during the penetration process, except for the initial stage (after collision) and the final stage (after rod erosion), satisfying the assumption of a constant velocity rod. When stable penetration occurs, the hollow tail skirt material continuously flows into the dense part to supplement its erosion loss with a gradual decrease in the length of the dense part. The length of the projectile can be increased to improve the penetration ability of EFP to a certain extent, but the normalized penetration depth decreases. The impact velocity and the length of dense part can be Increased to significantly enhance the penetration performance of rod-shaped EFP. The strength of rod-shaped EFP has a limited impact on penetration, but the target strength cannot be ignored. The density of target material is the main factor affecting the penetration of the projectile.

Key words: terminal effect, explosively formed penetrator, penetration performance, numerical simulation

CLC Number:

TJ410

WANG Yajun, YU Rui, LI Weibing, LI Wenbin. Research on the Penetration Characteristics of Rod-shaped EFP and Its Influencing Factors[J]. Acta Armamentarii, 2024, 45(S1): 174-182.

Figures/Tables 15

Fig.1 Numerical simulation model of rod-shaped EFP penetration

Table 1 Material parameters[15⇓-17]

参数	纯钽	45号钢
ρ/(g·cm^-3)	16.69	7.83
A/MPa	187	507
B/MPa	267	320
n	0.38	0.28
C	0.054	0.064
m	0.45	1.06
D₁	3.061	0.1
D₂	1.726	0.76
D₃	-2.012	1.57
D₄	-0.015	0.005
D₅	-0.776	-0.84
c/(cm·μs^-1)	0.3414	0.4569
S₁	1.2	1.49
S₂	0	0
S₃	0	0
γ₀	1.6	2.17
a	0	0.46
E₀/(J·m^-3)	0	0

Fig.2 Layout diagram of rod-shaped EFP penetration test

Fig.3 Comparison of simulated and test results of rod-shaped EFP penetration

Fig.4 Velocity distribution of rod-shaped EFP during penetration

Fig.5 Von Mises stress distribution of rod-shaped EFP and target during penetration

Fig.6 Shape changes of rod-shaped EFP during penetration

Fig.7 Variation curves of EFP penetration depth over time

Fig.8 Relationship between normalized penetration depthand length variation

Fig.9 Comparison of rod-shaped EFP penetration under different impact velocities

Fig.10 Changing curves of EFP penetration depth at different velocities

Fig.11 Changes of normalized penetration depths of rod-shaped EFPs with different materials with material density

Fig.12 Change of normalized penetration depth of rod-type EFPs with same density but different constitutions with yield strength

Fig.13 Variation curves of normalized depth penetrating into target plates made of different materials with target density

Fig.14 Variation curves of normalized penetration depth of rod-type EFPs with different strengths with density

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