Evolution of a shock wave generated by underwater electrical explosion of a single wire
Evolution of a shock wave generated by underwater electrical explosion of a single wire
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DOI：
10.1063/1.5092321
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发表时间：
2019-04
影响因子：
2.2
通讯作者：
A. Rososhek;S. Efimov;V. Gurovich;A. Virozub;S. Tewari;Y. Krasik
中科院分区：
文献类型：
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作者：
A. Rososhek;S. Efimov;V. Gurovich;A. Virozub;S. Tewari;Y. Krasik
本文报道了铜、铝导线水下电爆炸产生的圆柱形冲击波的实验、分析和数值研究结果。实验中使用微秒级时间尺度发生器产生1.2 μs上升时间的180 kA脉冲。利用阴影条纹图像研究了爆炸丝的径向膨胀和产生的冲击波。结果表明，冲击波扩展速度下降到声速的两个阶段：一个快速阶段，然后逐渐阶段。快速阶段发生在阻性电压达到最大值后的约1.5 μs内，然后在几十微秒内逐渐下降。结果表明，快速阶段的持续时间对应于主要能量沉积到丝材中的时间段。流体动力学模拟表明，在冲击波速度的快速下降有关的爆炸线的亚音速膨胀的演变，这导致相邻的水层的时间/空间压缩。对于冲击波速度逐渐减小的阶段，我们建立了一个简化的模型，该模型考虑了金属丝边界和冲击波阵面之间的均匀水密度。该模型的计算结果与实验得到的冲击波轨迹和金属丝的径向膨胀吻合得很好。
The results of an experimental, analytical, and numerical study of the cylindrical shock wave generated by the underwater electrical explosion of copper and aluminum wires are reported. Experiments were conducted using a microsecond timescale generator delivering ∼180 kA pulses with a 1.2 μs rise time. Shadow streak images were used to study the radial expansion of the exploding wire and the generated shock wave. It was found that the shock wave expansion velocity decreases to the velocity of sound in two stages: a fast stage and then a gradual stage. The fast stage occurs during ∼1.5 μs after the maximum of the resistive voltage is reached, and then, a gradual decrease occurs during several tens of microseconds. It was shown that the duration of the fast stage corresponds to the period of time when the main energy deposition into the wire occurs. Hydrodynamic simulations show that the fast decrease in the shock velocity is related to the evolution of the exploded wire's subsonic expansion, which leads to time/spatial compression of the adjacent water layer. For the gradual decrease stage of the shock wave velocity, we developed a simplified model, which considers uniform water density between the wire boundary and the shock wave front. The results of this model agree satisfactorily with the experimentally obtained shock wave trajectory and radial expansion of the wire.