Exploding-wire experiments and theory for metal conductivity evaluation in the sub-eV regime.

Area of Science:

• Plasma Physics
• Computational Physics
• Materials Science

Background:

• Pulsed high current densities applied to copper and silver wires generate high-density metal plasma.
• Atmospheric air serves as the background gas in these experiments.
• Accurate material equation of state (EOS) and transport properties are crucial for plasma simulations.

Purpose of the Study:

• To present numerical simulations of high-density metal plasma generated by pulsed high currents.
• To validate magnetohydrodynamic (MHD) models and electrical conductivity models in the sub-eV plasma regime.
• To compare the applicability of sophisticated conductivity models with a simpler empirical model.

Main Methods:

• One-dimensional magnetohydrodynamic (MHD) partial differential equations were solved simultaneously with circuit equations.
• The LANL sesame database was utilized for the material equation of state (EOS).
• Two electrical conductivity models were applied: Lee-More-Desjarlais (LMD), quantum LMD (QLMD), and an empirical model.

Main Results:

• Simulations using LMD and QLMD conductivity models demonstrated the accuracy of the MHD methodology in the sub-eV regime.
• The conductivity data from LMD and QLMD were found to be reliable for the simulated plasma conditions.
• An empirical conductivity model was evaluated for its temperature-density range of applicability against the LMD/QLMD models.

Conclusions:

• The employed MHD simulation framework and conductivity models (LMD, QLMD) are accurate for sub-eV, high-density metal plasmas.
• The study provides insights into the performance of different electrical conductivity models in this specific plasma regime.
• Further exploration of empirical models is warranted to understand their limitations and potential for computational efficiency.