Experimental study of conical liner magnetic implosion

Summary form only given. High matter velocities level (several tens of km/s) can be achieved by means of magnetic implosion, using explosive magnetic generators. Helical+Potok type generators developed by Russian Federal Institute of Research in Experimental Physics (VNIIEF) can provide 30 MJ inductive storage and, after fast explosive opening switch operation, current law in the range 15 MA within a few microseconds. This allows high velocity jet generation, due to conical aluminium liner implosion and focalization on axis. VNIIEF and the Commissariat l'Energie Atomique (CEA, France) used this principle to realize a joint experiment in Sarov by June, 30th, 1999. Electrical power supply was provided by VNIIEF, target with diagnostics by CEA. This experiment was a challenge, with regards to several points: unusual current level range, poor data available about such a device, very short duration for radiographic observation of main phenomena: liner focalization and subsequent fast matter emission along axis. Both radiographic flashes were realized at required times. Pictures show expected density gradients in liner when collapsing on axis. Moreover, liner external face structure exhibits machining defect growth under magnetic Rayleigh Taylor instability effect: this feature already appeared in previous liner flight experiments. The present experiment clearly shows magnetocumulative generator ability for high velocities purpose, machining precision effects under high current values, radiographic observation pertinency, and prediction calculation capacity to be close to experimental results.