Speaker
Description
Underwater electrical wire explosions have attracted much attention in the recent decade due to the high energy density deposition into the wire, which is possible because of the high breakdown voltage of water compared to air and vacuum, preventing surface breakdown. Moreover, water’s small compressibility also contributes to higher energy density deposition, with the plasma maintaining a higher resistivity state for a relatively long time.
During explosion the wire transforms to the plasma state which allows the study of equations of state and transport parameters in warm dense matter conditions. As the wire expands, shock waves are launched into the surrounding water; with cylindrical or spherical wire arrays, one can obtain converging shock waves which also generate extreme pressures on the axis of convergence.
Recently, a study in the Technion – Israel Institute of Technology, showed that using glycerol instead of water as a medium for cylindrical array explosions, increased the shock wave velocity by ~20%, and hence the pressure by ~2 times in the vicinity of convergence. In this presentation, we show the results of cylindrical wire array explosions in other different liquids, such as tungstate water, nitromethane, and in cast plastic. These materials have different densities and sound velocities which influence the generated shock wave velocities and thermodynamic parameters on axis. Also, explosions in plastic, in addition to having higher shock velocities, have the advantages of not needing waterproof systems, and the ability to make wire arrays in different adjustable shapes.
This work was sponsored by Sandia National Laboratories, First Light Fusion, and DOE Cooperative Agreement Nos. DOE Cooperative Agreement No DE-NA0003764
