Evidence of hydrodynamic processes in multimegampere copper fuses

Abstract

Experiments have been performed in which an explosively formed fuse transferred a fraction of the 10 MA output current from an explosively powered magnetic flux compression generator to a conventional exploding metallic fuse load. System malfunctions significantly reduced the current delivered to the load and changed the fuse performance. The resultant slowing of the fuse material’s trajectory through density-temperature space allowed a correlation between optical and electrical diagnostics which indicated a significant delay between the onset of hydrodynamic motion and the onset of rapid resistance increase. The experiments have confirmed a computational model of the fuse load hydrodynamic behavior.

Verification and validation adventures in simulating megagauss-magnetic-field-induced plasma formation on thickwire metallic surfaces

“…This structure is surprisingly similar to structure observed postexperiment in mylar tamping layers in fuse experiments where plasma formation was not intended [15]. A somewhat similar structure was obtained in photography of copper foils used as a load for a flux-compression generator [16]. It is not clear that this structure can be modeled, even in three-dimensions, using the typical approach of a single density-and temperature-dependent EOS, whether Maxwell-construct or van der Waals.…”