Particularities of shocks generated by underwater electrical explosions of a single wire and wire arrays

The results of experimental and numerical research of shockwaves generated by the underwater electrical explosion of a single wire and a planar wire array are reported. Experiments were conducted using a microsecond time scale pulse power generator delivering a <210 kA current with a <1 μs rise time. Streak and fast framing cameras were used to study the time- and space-resolved evolution of the shocks. The results show that (a) an aperiodic discharge constitutes the most efficient method of generating a shockwave; (b) in the case of a planar wire array, an almost simultaneous explosion can be obtained when the individual wire diameter is <100 μm (current density >2 × 107 A/cm2); (c) the planar shock velocity can be accelerated using the combustion properties of the Al wires efficiently, and (d) the shock velocity can be enhanced using a metal reflector placed below the array.