Electric field divertor plasma pump
Abstract
An electric field plasma pump includes a toroidal ring bias electrode (56) positioned near the divertor strike point of a poloidal divertor of a tokamak (20), or similar plasma-confining apparatus. For optimum plasma pumping, the separatrix (40) of the poloidal divertor contacts the ring electrode (56), which then also acts as a divertor plate. A plenum (54) or other duct near the electrode (56) includes an entrance aperture open to receive electrically-driven plasma. The electrode (56) is insulated laterally with insulators (63,64), one of which (64) is positioned opposite the electrode at the entrance aperture. An electric field E is established between the ring electrode (56) and a vacuum vessel wall (22), with the polarity of the bias applied to the electrode being relative to the vessel wall selected such that the resultant electric field E interacts with the magnetic field B already existing in the tokamak to create an E.times.B/B.sup.2 drift velocity that drives plasma into the entrance aperture. The pumped plasma flow into the entrance aperture is insensitive to variations, intentional or otherwise, of the pump and divertor geometry. Pressure buildups in the plenum or duct connected to the entrance aperture in excess of 10 mtorr are achievable.
- Inventors:
-
- San Diego, CA
- Issue Date:
- Research Org.:
- Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)
- Sponsoring Org.:
- USDOE
- OSTI Identifier:
- 869531
- Patent Number(s):
- 5353314
- Assignee:
- United States of America as represented by United States (Washington, DC)
- Patent Classifications (CPCs):
-
G - PHYSICS G21 - NUCLEAR PHYSICS G21B - FUSION REACTORS
Y - NEW / CROSS SECTIONAL TECHNOLOGIES Y02 - TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE Y02E - REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- DOE Contract Number:
- AC03-89ER51114; AC05-84OR21400; W-7405-ENG-48; AC04-76DP00789
- Resource Type:
- Patent
- Country of Publication:
- United States
- Language:
- English
- Subject:
- electric; field; divertor; plasma; pump; toroidal; bias; electrode; 56; positioned; near; strike; poloidal; tokamak; 20; similar; plasma-confining; apparatus; optimum; pumping; separatrix; 40; contacts; plate; plenum; 54; duct; entrance; aperture; receive; electrically-driven; insulated; laterally; insulators; 63; 64; opposite; established; vacuum; vessel; wall; 22; polarity; applied; relative; selected; resultant; interacts; magnetic; existing; create; times; drift; velocity; drives; pumped; flow; insensitive; variations; intentional; otherwise; geometry; pressure; buildups; connected; excess; 10; mtorr; achievable; bias applied; poloidal divertor; vessel wall; vacuum vessel; electric field; magnetic field; positioned near; positioned opposite; drift velocity; receive electrical; duct connected; pressure buildup; plasma pump; /376/
Citation Formats
Schaffer, Michael J. Electric field divertor plasma pump. United States: N. p., 1994.
Web.
Schaffer, Michael J. Electric field divertor plasma pump. United States.
Schaffer, Michael J. Sat .
"Electric field divertor plasma pump". United States. https://www.osti.gov/servlets/purl/869531.
@article{osti_869531,
title = {Electric field divertor plasma pump},
author = {Schaffer, Michael J},
abstractNote = {An electric field plasma pump includes a toroidal ring bias electrode (56) positioned near the divertor strike point of a poloidal divertor of a tokamak (20), or similar plasma-confining apparatus. For optimum plasma pumping, the separatrix (40) of the poloidal divertor contacts the ring electrode (56), which then also acts as a divertor plate. A plenum (54) or other duct near the electrode (56) includes an entrance aperture open to receive electrically-driven plasma. The electrode (56) is insulated laterally with insulators (63,64), one of which (64) is positioned opposite the electrode at the entrance aperture. An electric field E is established between the ring electrode (56) and a vacuum vessel wall (22), with the polarity of the bias applied to the electrode being relative to the vessel wall selected such that the resultant electric field E interacts with the magnetic field B already existing in the tokamak to create an E.times.B/B.sup.2 drift velocity that drives plasma into the entrance aperture. The pumped plasma flow into the entrance aperture is insensitive to variations, intentional or otherwise, of the pump and divertor geometry. Pressure buildups in the plenum or duct connected to the entrance aperture in excess of 10 mtorr are achievable.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Sat Jan 01 00:00:00 EST 1994},
month = {Sat Jan 01 00:00:00 EST 1994}
}
Works referenced in this record:
Poloidal divertor experiment with applied E⃗×B⃗ /B 2 drift
journal, August 1981
- Strait, E. J.
- Nuclear Fusion, Vol. 21, Issue 8
Experimental demonstration of E×B plasma divertor
journal, January 1978
- Strait, E. J.; Kerst, D. W.; Sprott, J. C.
- Physics of Fluids, Vol. 21, Issue 12
Plasma behavior with a separatrix magnetic surface in JFT−2a tokamak
journal, January 1976
- Shimomura, Y.; Maeda, H.; Ohtsuka, H.
- Physics of Fluids, Vol. 19, Issue 10