Plasma Jet Formation Disruption From a Critical Applied Uniform Axial Magnetic Field

摘要: We examine the effects of varying magnitude an applied, uniform, axial magnetic field ( $B_{z}$ ) on formation laboratory plasma jets produced by a 1-MA 100-ns rise time pulsed power generator in radial foil configuration. A Helmholtz coil applies external (0 to 2 T). With small-enough applied field, surface ablation is relatively azimuthally and $J\times B$ forces drive ablated inward upward form well-defined symmetric jet. Using strengths larger than critical $B_{z} = 1.1\pm 0.1$ T with aluminum foils, not discrete bursts initiate from surface, jet disrupted. The for this disruption correlates material’s electrical resistivity equation state (EOS). To better understand material-dependent phenomenon, we compare experimental results 3-D extended magnetohydrodynamics simulations mm $\times 2$ 25- $\mu \text{m}$ slab that represents section foil. initialize solid include material EOS phases. As observed disruption, these show enhanced nonuniform , which can inhibit azimuthal uniformity necessary produce Furthermore, also dependence process similar trend shown experiments. These demonstrate necessity accurate, detailed modeling properties during transition