Current channel migration and magnetic field penetration in a perfectly conducting plasma with emitting, conducting boundaries

Grossmann, J. M.; Ottinger, P. F.; Mason, Rodney J.

doi:10.1063/1.344287

Cited by 22 publications

(5 citation statements)

References 28 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This assumption agrees with experimental data on the penetration of a magnetic field into a plasma with a roughly constant current density (Weber et al 1987). The drift of electrons occurs in crossed magnetic and axial polarization electric fields E pol (t) = j dr B(t)/enc (Grossmann et al 1986;Grossmann, Ottinger & Mason 1989). The polarization field arises due to charge separation during the motion of electrons in the current channel.…”

Section: Collisionless Plasmasupporting

confidence: 87%

See 1 more Smart Citation

Self-magnetic insulation in plasma opening switches

Loginov

2020

J. Plasma Phys.

View full text Add to dashboard Cite

The paper analyses the penetration of a magnetic field into the plasma bridge of nanosecond and microsecond opening switches. For switches with a conduction time of ~100 ns, simple formulae are derived to estimate the magnetic field velocity in collisionless and collisional plasmas. It is shown that in both cases this velocity is determined by the magnetic field rise rate to plasma density ratio raised to the power of 1/2. As the conduction time is increased to ~1 ${\rm \mu}$ s, the field velocity starts to depend on the plasma aggregation by a magnetic piston. At the same time, irrespective of the conduction time, the electron flow velocity is limited by the radial drift velocity in crossed magnetic and polarization electric fields. Such a limitation suppresses the current channel conductivity with respect to the Spitzer value by a factor equal to the electron magnetization parameter raised to one or another power. On completion of the conduction phase, the rate of rise of the switch resistance is proportional to the electron drift velocity. The peak switch voltage obtained in calculations is compared with its values recorded in experiments on mega-ampere current switching. A procedure is also presented for calculating the switch parameters to obtain the maximum possible voltage in the phase of current cutoff.

show abstract

Section: Collisionless Plasmasupporting

confidence: 87%

“…The drift of electrons occurs in crossed magnetic and axial polarization electric fields (Grossmann et al. 1986; Grossmann, Ottinger & Mason 1989). The polarization field arises due to charge separation during the motion of electrons in the current channel.…”

Section: Conduction Phasementioning

confidence: 99%

Self-magnetic insulation in plasma opening switches

Loginov

2020

J. Plasma Phys.

View full text Add to dashboard Cite

show abstract

“…Interferometric 22,23 and spectroscopic 15 measurements have also shown the propagation of an electron density rise followed by a significant drop. Additionally, early simulations [24][25][26] and models 27 pointed out to the possibility of a developing potential that could result in ion separation. Indeed, later experiments revealed complex ion dynamics.…”

mentioning

confidence: 99%

The structure of a magnetic-field front propagating non-diffusively in low-resistivity multi-species plasma

et al. 2016

View full text Add to dashboard Cite

We report on the first experimental verification of the traveling-wave-like picture of a magnetic-field and an associated electric potential hill propagating non-diffusively in low resistivity plasma. High spatial resolution spectroscopic method, developed here, allowed for obtaining the detailed shape of the propagating magnetic-field front. The measurements demonstrated that the ion separation, previously claimed, results from the reflection of the higher charge-to-mass ratio ions from the propagating potential hill and from climbing the hill by the lower charge-to-mass ratio ions. This ion dynamics is found to be consistent with the observed electron density evolution.

show abstract

“…In the case of weakly collisional plasma, the thickness of the shock front is , where is the electron frequency. Fast magnetic field penetration was also predicted by fluid code [19] and particle-in-cell (PIC) code [20], [21] simulations of the POS, which also show a positive floating-potential plasma with respect to both POS electrodes behind the current channel.…”

Section: Discussionmentioning

confidence: 78%

Energetic electron and ion beam generation in plasma opening switches

Krasik

Weingarten

1998

IEEE Trans. Plasma Sci.

View full text Add to dashboard Cite

Abstract-In this paper, we present measurements of ion and electron flows in a nanosecond plasma opening switch (NPOS) and a microsecond plasma opening switch (MPOS), performed using charge collectors. In both experiments, an electron flow toward the anode, followed by an ion flow, were observed to propagate downstream toward the load side of the plasma during the plasma opening switch (POS) conduction. In the MPOS, ion acceleration was observed to propagate axially through the entire plasma. These results are in satisfactory agreement with the predictions of the electron magneto-hydrodynamics (EHMD) theory and the results of fluid and particle-in-cell (PIC) code simulations. At the beginning of the POS opening, a high-current density ( 2 kA/cm 2 ) short-duration (10-30 ns) axial ion flow downstream toward the load was observed in both experiments, with an electron beam in front of it. These ions are accelerated at the load side of the plasma and are accompanied by comoving electrons. In the NPOS, the ion energy reaches 1.35 MeV, whereas in the MPOS, the ion energy does not exceed 100 keV. We suggest that in the NPOS the dominant mechanism for the axial ion acceleration is collective acceleration by the space charge of the electron beam, while in the MPOS, axial ion acceleration is probably governed by the Hall field in the current carrying plasma.Index Terms-Acceleration, electron beams, Hall effect, inductive energy storage, ion beams, plasmas, power generation, pulse power system switches.

show abstract

Current channel migration and magnetic field penetration in a perfectly conducting plasma with emitting, conducting boundaries

Abstract: Density fluctuations and current penetration on a magnetized plasma column Phys. Fluids 28, 554 (1985); 10.1063/1.865120Enhanced penetration of fieldaligned currents into a Lorentz plasma in a stochastic magnetic field

Cited by 22 publications

References 28 publications

Self-magnetic insulation in plasma opening switches

Self-magnetic insulation in plasma opening switches

The structure of a magnetic-field front propagating non-diffusively in low-resistivity multi-species plasma

Energetic electron and ion beam generation in plasma opening switches

Contact Info

Product

Resources

About