Exploding wires (EWs) are subjected to high current densities of the order of 107 A/cm2 inducing metal vaporization and plasma formation on a microsecond timescale. Single strand EWs, silver and copper, are tested in gaseous media from atmospheric pressure to 790 kPa. To theoretically predict EW behavior, one-dimensional, radially directed cylindrical, Lagrangian coordinate hydrodynamic (HD) and magnetohydrodynamic (MHD) models are applied. Such models require accurate material equation-of-state (EOS) and electrical conductivity data throughout the temperature density range experimentally achieved (ρ = 0.1–10 gm/cm3 and T = 300–20,000 K). In this study, the Lee-More-Desjarlais (LMD) conductivity, and its quantum molecular dynamic modification (QLMD) are used. The Los Alamos National Laboratory SESAME database is employed as EOS parameter input. When utilized as an opening switch the metal plasma is exposed to higher electric fields, atypical to traditional exploding wire experiments. Recent studies have shown that the behavior of the strongly coupled plasma in such conditions is reasonably well modeled assuming a semi-empirical electron impact ionization process. The HD and MHD based models are benchmarked against experimental data to confirm their accuracy for predicting the behavior of EWs in an opening switch type operation.
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机译：爆炸丝（EW）承受的高电流密度约为10 7 A / cm 2 ，在微秒级的时间内引起金属的汽化和等离子体的形成。在大气压至790 kPa的气态介质中对银和铜单链EW进行了测试。为了从理论上预测电子战行为，应用了一维，径向圆柱，拉格朗日坐标流体力学（HD）和磁流体力学（MHD）模型。此类模型需要在实验达到的整个温度密度范围内（ρ= 0.1–10 gm / cm 3 和T = 300–20,000 K）准确的材料状态方程（EOS）和电导率数据。在这项研究中，使用了Lee-More-Desjarlais（LMD）电导率及其量子分子动态修饰（QLMD）。洛斯阿拉莫斯国家实验室SESAME数据库被用作EOS参数输入。当用作断开开关时，金属等离子体暴露于更高的电场，这是传统爆炸丝实验所不具备的。最近的研究表明，假设半经验电子碰撞电离过程，在这种条件下强耦合等离子体的行为可以得到很好的建模。基于HD和MHD的模型已针对实验数据进行了基准测试，以确认它们在预测断开式操作中EW行为时的准确性。
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