Electric field divertor plasma pump
Abstract
An electric field plasma pump includes a toroidal ring bias electrode positioned near the divertor strike point of a poloidal divertor of a tokamak, or similar plasma-confining apparatus. For optimum plasma pumping, the separatrix of the poloidal divertor contacts the ring electrode, which then also acts as a divertor plate. A plenum or other duct near the electrode includes an entrance aperture open to receive electrically-driven plasma. The electrode is insulated laterally with insulators, one of which is positioned opposite the electrode at the entrance aperture. An electric field E is established between the ring electrode and a vacuum vessel wall, 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. 11 figs.
- Inventors:
- Issue Date:
- OSTI Identifier:
- 6936860
- Patent Number(s):
- 5353314
- Application Number:
- PPN: US 7-769633
- Assignee:
- Dept. of Energy, Washington, DC (United States)
- DOE Contract Number:
- AC03-89ER51114; AC05-84OR21400; W-7405-ENG-48; AC04-76DP00789
- Resource Type:
- Patent
- Resource Relation:
- Patent File Date: 30 Sep 1991
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; DIVERTORS; PUMPS; DESIGN; TOKAMAK DEVICES; PLASMA DRIFT; PLASMA PRESSURE; POSITIONING; CLOSED PLASMA DEVICES; THERMONUCLEAR DEVICES; 700420* - Fusion Technology- Plasma-Facing Components- (1992-)
Citation Formats
Schaffer, M J. Electric field divertor plasma pump. United States: N. p., 1994.
Web.
Schaffer, M J. Electric field divertor plasma pump. United States.
Schaffer, M J. Tue .
"Electric field divertor plasma pump". United States.
@article{osti_6936860,
title = {Electric field divertor plasma pump},
author = {Schaffer, M J},
abstractNote = {An electric field plasma pump includes a toroidal ring bias electrode positioned near the divertor strike point of a poloidal divertor of a tokamak, or similar plasma-confining apparatus. For optimum plasma pumping, the separatrix of the poloidal divertor contacts the ring electrode, which then also acts as a divertor plate. A plenum or other duct near the electrode includes an entrance aperture open to receive electrically-driven plasma. The electrode is insulated laterally with insulators, one of which is positioned opposite the electrode at the entrance aperture. An electric field E is established between the ring electrode and a vacuum vessel wall, 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. 11 figs.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {1994},
month = {10}
}