Title :
Planning of Experiments for Justification of Enhanced Resistivity in a Strongly Inhomogeneous Wire-Array Plasma
Author :
Rudakov, L.I. ; Kantsyrev, V.L.
Author_Institution :
Icarus Res., Inc., Bethesda, MD
Abstract :
Summary form only given. Recent experimental data demonstrate that wire array loads (a) radiate more energy than could be coupled to them via a change of inductance, and (b) start radiating before the main mass stagnates on the axis. This indicates that the wire array plasma operates as a resistive rather than an inductive load. Recently it was suggested that it may be because of the wire array plasma being very inhomogeneous prior to stagnation (radial flares, jets, etc.). It is known that penetration of a magnetic field into a strongly inhomogeneous medium with magnetized electrons, OmegaetaueGt1 , is very different from classical diffusion into a conducting fluid and looks like the magnetic field advection by the electron flow along trajectories, conserving the value of B/ne=const. We propose an experiment to measure effective resistivity of such a plasma, which is predicted to be enhanced by a factor (Omegaetaue)2. The interpretation of the radiation yield of the cylindrical wire array load always meets some uncertainties. The magnetic energy deposition due to the load inductance changing DeltaL=ln(R0/Rfinal ) can not be calculated accurately because the current distribution across the plasma pinch is unknown. To avoid these uncertainties we suggest to implode two planar array, 10-15 Al wires in each, connected in parallel. UNR generator can deliver to the load 1 MA current in 100 ns. We estimate the energy which can be dissipated on the resistor as ~10 kJ in ~20 ns when DeltaLI2/2 is ~1 kJ
Keywords :
aluminium; exploding wires; explosions; pinch effect; plasma magnetohydrodynamics; plasma transport processes; 1 MA; 100 ns; Al; conducting fluid; current distribution; cylindrical wire array load; diffusion; electron flow; inhomogeneous wire-array plasma; load inductance; magnetic energy deposition; magnetic field advection; magnetized electrons; plasma pinch; plasma resistivity; radiation yield; Conductivity; Current distribution; Electrons; Inductance; Magnetic field measurement; Magnetic fields; Magnetic liquids; Plasma measurements; Uncertainty; Wire;
Conference_Titel :
Plasma Science, 2005. ICOPS '05. IEEE Conference Record - Abstracts. IEEE International Conference on
Conference_Location :
Monterey, CA
Print_ISBN :
0-7803-9300-7
DOI :
10.1109/PLASMA.2005.359122