Abstract/Details

NEUTRAL BEAM DRIVEN IMPURITY FLOW REVERSAL IN TOKAMAKS (FUSION, PLASMA)

BENNETT, RICHARD BYRON.  Georgia Institute of Technology. ProQuest Dissertations Publishing, 1984. 8411311.

Abstract (summary)

A theory for the effect of neutral beam injection on the transport of impurity ions in a tokamak plasma was extended to include the effect of temperature gradients. A theory for the effect of neutral beam momentum input on the radial heat conduction was also developed. Injection of neutral beam momentum in the direction of the toroidal magnetic field, called co-injection, was found to reverse the normally inward flow of impurities. The theory was found to provide a reasonable basis for interpretation of impurity flow reversal experiments performed in the Princeton Large Torus (PLT), when a multiplicative factor of two was applied to the predicted impurity fluxes.

The model that was adjusted to fit the experimental results in PLT was then applied to the Tokamak Fusion Test Reactor (TFTR) and to models based on designs of future tokamaks. Using the maximum available co-injected beam power (16 MW) in TFTR is predicted to lead to a substantial reduction (relative to balanced momentum injection) in the penetration of impurities to the center of the discharge and to substantially increase the impurity radiation from the plasma edge. This would possibly lead to a cold, radiating edge which would reduce sputtering erosion of the limiter. A modest amount (30 MW) of co-injected beam power is predicted to substantially reduce the penetration of impurities to the center of models of the Fusion Engineering Device (FED) and the STARFIRE commercial reactor. If these plasmas operate with a high edge density, as would be the case with a high rate of edge recycling, this amount of co-injected power is also sufficient to significantly increase the impurity radiation from the edge region, again possibly leading to a cold radiating edge and associated reduction in limiter erosion.

Indexing (details)


Subject
Fluid dynamics;
Gases
Classification
0759: Fluid dynamics
0759: Gases
Identifier / keyword
Pure sciences
Title
NEUTRAL BEAM DRIVEN IMPURITY FLOW REVERSAL IN TOKAMAKS (FUSION, PLASMA)
Author
BENNETT, RICHARD BYRON
Number of pages
273
Degree date
1984
School code
0078
Source
DAI-B 45/02, Dissertation Abstracts International
Place of publication
Ann Arbor
Country of publication
United States
ISBN
9798661949790
University/institution
Georgia Institute of Technology
University location
United States -- Georgia
Degree
Ph.D.
Source type
Dissertation or Thesis
Language
English
Document type
Dissertation/Thesis
Dissertation/thesis number
8411311
ProQuest document ID
303294151
Copyright
Database copyright ProQuest LLC; ProQuest does not claim copyright in the individual underlying works.
Document URL
https://www.proquest.com/docview/303294151/abstract