Cross-field diffusion quenching by neutral gas injection in a magnetized plasma

In this paper it is shown that a stationary plasma can be accelerated by a moving neutral gas only if the velocity of the neutral gas exceeds Alfvén's critical velocity. An expression for the terminal velocity of the interaction is given which shows that, in the limit of high incoming neutral gas speeds, the composite plasma is accelerated up to one quarter of the gas speed. We also discuss terminal velocities associated with the inverse problem, namely the deceleration of a magnetized plasma as a result of its motion through, and interaction with, a stationary neutral gas.

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Local Neutral Density Enhancement by Streaming Neutral Gas Injection

Japanese Journal of Applied Physics ◽

10.1143/jjap.45.5936 ◽

2006 ◽

Vol 45 (7) ◽

pp. 5936-5939 ◽

Cited By ~ 1

Author(s):

Alexander G. Mendenilla ◽

Toshiro Kasuya ◽

Motoi Wada

Keyword(s):

Gas Injection ◽

Neutral Density ◽

Neutral Gas ◽

Density Enhancement

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On Alfv�n's critical velocity for the interaction of a neutral gas with a moving magnetized plasma

Astrophysics and Space Science ◽

10.1007/bf00642583 ◽

1978 ◽

Vol 55 (1) ◽

pp. 113-124 ◽

Cited By ~ 18

Author(s):

R. K. Varma

Keyword(s):

Critical Velocity ◽

Magnetized Plasma ◽

Neutral Gas

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Three-Dimensional Modeling of Solar Thermochemical Splitting of CO2 in a CR5

ASME 2011 5th International Conference on Energy Sustainability, Parts A, B, and C ◽

10.1115/es2011-54536 ◽

2011 ◽

Author(s):

Ken S. Chen ◽

Roy E. Hogan

Keyword(s):

Chemical Reactions ◽

Gas Injection ◽

Three Dimensional ◽

Generation Model ◽

Three Dimensional Modeling ◽

Neutral Gas ◽

Solar Thermochemical ◽

Multiple Species ◽

Carbon Dioxide Co2 ◽

Efficiency Effects

A three-dimensional (3-D) numerical model for simulating the process of solar thermochemical splitting of carbon dioxide (CO2) into carbon monoxide (CO) in a counter-rotating-ring receiver/reactor/recuperator or CR5 are developed in order to account for three-dimensional effects such as edge effect of side walls. The present 3-D model, which is based on our previous two-dimensional first-generation model, takes into account heat transfer, gas-phase flow, multiple-species transport in open channels and through pores of the porous reactant layer, and redox chemical reactions at the gas/solid interfaces. Sample computed results (e.g., temperature distribution, species concentration contours) are presented to illustrate model utility. The model is employed to examine the effects of rates of CO2 and argon neutral gas injection and the redox chemical reactions on thermochemical solar conversion efficiency. Effects of the CR5 width and argon neutral gas injection on O2 crossover are also explored.

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Enhancement of extracted H− current by streaming neutral gas injection

Thin Solid Films ◽

10.1016/j.tsf.2005.08.112 ◽

2006 ◽

Vol 506-507 ◽

pp. 527-530 ◽

Cited By ~ 2

Author(s):

Alexander Mendenilla ◽

Hidenori Takahashi ◽

Toshiro Kasuya ◽

Motoi Wada

Keyword(s):

Gas Injection ◽

Neutral Gas

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The Effect of Ionization and Recombination on the Resistivity of a Partially Ionized Plasma in a Magnetic Field

Australian Journal of Physics ◽

10.1071/ph780171 ◽

1978 ◽

Vol 31 (2) ◽

pp. 171 ◽

Cited By ~ 5

Author(s):

CD Mathers ◽

NF Cramer

Keyword(s):

Magnetic Field ◽

Major Effect ◽

Magnetized Plasma ◽

Neutral Atoms ◽

Laboratory Conditions ◽

Electron Atom ◽

Neutral Gas ◽

Partially Ionized ◽

Three Body ◽

The Magnetic Field

The generalized Ohm's law for a partially ionized magnetized plasma composed of ions, electrons and neutral atoms is calculated. The plasma is modelled by a three-fluid treatment, with elastic collisions between all three species, as well as inelastic ionization and recombination collisions being taken into account. Ionization is assumed to be due to electron-atom impacts, and recombination is assumed to be due to three-body electron-electron-atom collisions. The resistivity is calculated, and it is shown that the major effect of ionization and recombination is to reduce the resistivity for currents perpendicular to the magnetic field under typical laboratory conditions. However, this resistivity is still greater than Coulomb resistivity, owing to plasma-neutral gas friction.

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Comparative study of the surface potential of magnetic and non-magnetic spherical objects in a magnetized radio-frequency discharge

Journal of Plasma Physics ◽

10.1017/s0022377820001130 ◽

2020 ◽

Vol 86 (5) ◽

Author(s):

Mangilal Choudhary ◽

Roman Bergert ◽

Slobodan Mitic ◽

Markus H. Thoma

Keyword(s):

Magnetic Field ◽

Surface Potential ◽

Debye Length ◽

Rate Of Change ◽

Magnetized Plasma ◽

Dust Particles ◽

Capacitively Coupled ◽

Spherical Probe ◽

Field Diffusion ◽

Magnetic Sphere

We report measurements of the time-averaged surface floating potential of magnetic and non-magnetic spherical probes (or large dust particles) immersed in a magnetized capacitively coupled discharge. In this study, the size of the spherical probes is taken greater than the Debye length. The surface potential of a spherical probe first increases, i.e. becomes more negative at low magnetic field ( $B < 0.05\ \textrm {T}$ ), attains a maximum value and decreases with further increase of the magnetic field strength ( $B > 0.05\ \textrm {T}$ ). The rate of change of the surface potential in the presence of a $B$ -field mainly depends on the background plasma and types of material of the objects. The results show that the surface potential of the magnetic sphere is higher (more negative) compared with the non-magnetic spherical probe. Hence, the smaller magnetic sphere collects more negative charges on its surface than a bigger non-magnetic sphere in a magnetized plasma. The different sized spherical probes have nearly the same surface potential above a threshold magnetic field ( $B > 0.03\ \textrm {T}$ ), implying a smaller role of size dependence on the surface potential of spherical objects. The variation of the surface potential of the spherical probes is understood on the basis of a modification of the collection currents to their surface due to charge confinement and cross-field diffusion in the presence of an external magnetic field.

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