Calculations of Neutral Beam Ion Confinement for the National Spherical Torus Experiment

Technical Report · Thu Jun 27 04:00:00 EDT 2002

DOI:https://doi.org/10.2172/803990· OSTI ID:803990

Redi, M H ^[1]; Darrow, D S; Egedal, J; Kaye, S M; White, R B

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1. Princeton Plasma Physics Laboratory

The spherical torus (ST) concept underlies several contemporary plasma physics experiments, in which relatively low magnetic fields, high plasma edge q, and low aspect ratio combine for potentially compact, high beta and high performance fusion reactors. An important issue for the ST is the calculation of energetic ion confinement, as large Larmor radius makes conventional guiding center codes of limited usefulness and efficient plasma heating by RF and neutral beam ion technology requires minimal fast ion losses. The National Spherical Torus Experiment (NSTX) is a medium-sized, low aspect ratio ST, with R=0.85 m, a=0.67 m, R/a=1.26, Ip*1.4 MA, Bt*0.6 T, 5 MW of neutral beam heating and 6 MW of RF heating. 80 keV neutral beam ions at tangency radii of 0.5, 0.6 and 0.7 m are routinely used to achieve plasma betas above 30%. Transport analyses for experiments on NSTX often exhibit a puzzling ion power balance. It will be necessary to have reliable beam ion calculations to distinguish among the source and loss channels, and to explore the possibilities for new physics phenomena, such as the recently proposed compressional Alfven eigenmode ion heating.

• Research Organization: Princeton Plasma Physics Lab., NJ (US)
• Sponsoring Organization: USDOE Office of Science (US)
• DOE Contract Number: AC02-76CH03073
• OSTI ID: 803990
• Report Number(s): PPPL-3714
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
ASPECT RATIO
CONFINEMENT
HEATING
LARMOR RADIUS
MAGNETIC FIELDS
PERFORMANCE
PHYSICS
PLASMA
PLASMA HEATING
THERMONUCLEAR REACTORS
TRANSPORT