Abstract：For confirming the mechanism of the passive electromagnetic armor, the characteristics of the current effect on shaped charge jet are researched. Based on the equivalent circuit model, time and frequency characteristic of pulse current are analyzed and a frequency-domain analysis method of skin effect is introduced. Calculation method of pulse current density distribution in shaped charge jet is obtained and the change rule of the skin depth during the discharge is researched. Calculation errors are given and the validity of the analysis method is approved by contrasting with the FEM analysis results. Finally, distribution characteristic of the current effect on the shaped charge jet element is obtained based on action time model. The results indicate that, pulse current is broadband distribution, and its current distribution is different from single-frequented time-harmonic current. Current density increases with depth decreases not all the time. It declines on the surface of the conductor at the trailing edge of the pulse current. And the current effect is concentrated on tail of the jet whose velocity is less than 4km/s, while the effect intensity becomes larger as the element closer to the surface.
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