线圈脉冲电流对破甲弹金属射流箍缩特性的影响

为了研究线圈脉冲电流参数对破甲弹金属射流箍缩特性的影响, 提出了均匀线圈中脉冲电流作用下不均匀粗细金属射流磁感应强度、感应电流密度及箍缩电磁力分布的理论模型, 建立了线圈与金属射流作用的有限元模型, 分析了励磁线圈中所施加脉冲电流参数对金属射流的影响规律。结果表明, 随着励磁线圈中所施加脉冲电流幅值的增大, 金属射流中的感应电流密度、磁感应强度及电磁力也随之增大, 励磁线圈中所施加的脉冲电流幅值J_max≥1×1010 A/m2, 才能保证金属射流可靠变形；随着励磁线圈中所施加脉冲电流频率的增加, 金属射流中的感应电流密度、磁感应强度及电磁力整体均呈现一定程度的趋肤效应, 且在一定的频率范围内, 趋肤层逐渐变薄, 分析得知, 当励磁线圈中脉冲电流的频率满足50 kHz≤f≤100 kHz时, 就能够保证金属射流发生有效变形, 进而延缓金属射流箍缩直至断裂的过程。

Effect of pulsed current of coil on pinching characteristics of shaped charge jet

In the present study,to analyze how the parameters of the coil's pulsed current affect the pinching characteristics of the shaped charge jet (SCJ),theoretical models considering the induced current density,the magnetic flux intensity and the pinching electromagnetic force distribution of uneven SCJ in the coil's pulsed current were established,a finite element model of the SCJ and the coil was built,and the effect of the pulsed current parameters of the magnetic exciting coil on the SCJ was analyzed.The results show that as the pulsed current amplitude of the coil increases,so do the induced current density,the magnetic flux density and the pinching electromagnetic force of the SCJ,that the effective deformation of the SCJ occurs only when the pulsed current density amplitude through the coil is bigger than 1 × 1010 A/m2,and that with the increase of the pulsed current frequency of the coil,the induced current density,the magnetic flux density and the pinching electromagnetic force of the SCJ show a certain degree of the skin effect,and the skin layer gradually becomes thinner within a certain frequency range.Analysis shows that it is when the pulsed current frequency of the coil is between 50 kHz and 100 kHz that the effective deformation of the SCJ can be ensured,thereby delaying its breakage process.