Untersuchungen zur Stromdichteverteilung eines Lichtbogens im Magnetfeld

Abstract

In a cylindrical arc without external magnetic field the radius of the discharge current is identi-cal with that of the conductive plasma column. It is shown here that, in general, this is not the case in an arc with superposed magnetic field. Instead, the current is limited by the magnetic flux tube whose cross section is governed by that of the electrodes. This is still true if the radius of the conductive plasma column is much larger than that of the flux tube. In this case electromotive forces prevent radial expansion of the current carrying region and form a potential distribution in keeping with the current density distribution.

Investigation of oscillations and anomalous transport in a hydrogen hollow cathode discharge by a spatially three-dimensional two-fluid model

“…Thus, the (E ×B) drift frequency at any radial position r = R depends on the axial variation of the arc current flowing through the cross section of radius R. Similar arguments were discussed before in [32,48,52,53]. The plasma potential will increase from the plasma centre towards the plasma edge (∂ /∂r > 0), if the current carrying regions broadens from the cathode towards the anode (∂I (R)/∂z > 0; note that for the case discussed here j z < 0 and therefore I < 0, see figure 1).…”

Zur Begrenzung der radial en Ausdehnung des Li chtbogenstromes durch ein axiales Magnetfeld. II. Skalengesetze und Vergleich mit Experimenten / On Limitation of the Radial Extent of the Arc Current by Means of an Axial Magnetic Field. II. Scaling Laws and Comparison with Experimental Results

“…(8) und (9). Die in diesen Gleichungen auftretenden Funktionen C(k) und D(K) sind so zu bestimmen, daß das Potential auf den Elektroden konstant ist, und daß die Stromdichte, bzw.…”