Title :
Numerical investigation of plasma heating by induced azimuthal current at the electrical explosion of wires in the extra high magnetic field
Author :
Kolgatin, S.N. ; Shneerson, German A.
Author_Institution :
State Tech. Univ., St. Petersburg, Russia
Abstract :
Summary form only given, as follows. It is known that extra high axial magnetic field can stabilize the electrical explosion of wires. It causes additional plasma heating by the azimuthal current. The latter is induced in the conductive medium as it expands. For the numerical investigation of the process a mathematical model is adopted comprising the medium described by the MHD equations, which are solved simultaneously with the state equations and those expressing conductivity dependence on the temperature and density within the wide range of medium parameters. The calculations have shown that in the "stiff" explosion conditions when the calculated axial current density exceeded 10/sup 8/ A/cm/sup 2/, the azimuthal current is induced in plasma which has a substantially higher density than the axial one. The space-time flow pattern was investigated. The temperature peak is noted on the plasma cloud boundary where the temperature is in the order of 10/sup 2/ eV. The threshold character of the process is noted. The substantial additional heating is observed only in the field close to the megagauss range. The radiation losses are estimated.
Keywords :
current density; exploding wires; losses; plasma boundary layers; plasma density; plasma flow; plasma heating; plasma magnetohydrodynamics; plasma temperature; temperature; MHD equations; axial current density; azimuthal current; conductive medium; conductivity dependence; density; electrical explosion; extra high magnetic field; induced azimuthal current; mathematical model; medium parameters; megagauss range; numerical investigation; plasma cloud boundary; plasma heating; radiation losses; space-time flow pattern; state equations; stiff explosion conditions; temperature; temperature peak; threshold character; wires; Azimuthal current; Equations; Explosions; Heating; Magnetic fields; Magnetohydrodynamics; Mathematical model; Plasma density; Plasma temperature; Wires;
Conference_Titel :
Plasma Science, 1995. IEEE Conference Record - Abstracts., 1995 IEEE International Conference on
Conference_Location :
Madison, WI, USA
Print_ISBN :
0-7803-2669-5
DOI :
10.1109/PLASMA.1995.531648