Actions for High beta, Long Pulse, Bootstrap Sustained Scenarios on the National Spherical Torus Experiment (NSTX) [electronic resource].
High beta, Long Pulse, Bootstrap Sustained Scenarios on the National Spherical Torus Experiment (NSTX) [electronic resource].
- Published
- Washington, D.C : United States. Dept. of Energy. Office of Energy Efficiency and Renewable Energy, 2003.
Oak Ridge, Tenn. : Distributed by the Office of Scientific and Technical Information, U.S. Dept. of Energy. - Physical Description
- 2.7 Megabytes pages : digital, PDF file
- Additional Creators
- United States. Department of Energy. Office of Energy Efficiency and Renewable Energy, United States. Department of Energy. Office of Science, and United States. Department of Energy. Office of Scientific and Technical Information
Access Online
- Restrictions on Access
- Free-to-read Unrestricted online access
- Summary
- Long-pulse, high-beta scenarios have been established on the National Spherical Torus Experiment (NSTX). Beta(sub)t(always equal to 2μ(sub)0·
/B²(sub)t0) ≈ 35% has been achieved during transient discharges. The machine improvements that lead to these results, including error field reduction and high-temperature bakeout of plasma-facing components are described. The highest Beta(sub)t plasmas have high triangularity (delta = 0.8) and elongation (k = 2.0) at low-aspect ratio A always equal to R/a = 1.4. The strong shaping permits large values of normalized current, I(sub)N(always equal to I(sub)p /(aB(sub)t0)) approximately equal to 6 while maintaining moderate values of q(sub)95 = 4. Long-pulse discharges up to 1 sec in duration have been achieved with substantial bootstrap current. The total noninductive current drive can be as high as 60%, comprised of 50% bootstrap current and ≈10% neutral-beam current drive. The confinement enhancement factor H89P is in excess of 2.7. Beta(sub)N * H(sub)89P approximately or greater than 15 has been maintained for 8 * tau(sub)E ≈ 1.6 * tau(sub)CR, where tau(sub)CR is the relaxation time of the first radial moment of the toroidal current density. The ion temperature for these plasmas is significantly higher than that predicted by neoclassical theory.
- Report Numbers
- E 1.99:pppl-3791
pppl-3791 - Subject(s)
- Other Subject(s)
- Note
- Published through SciTech Connect.
02/26/2003.
"pppl-3791"
D.A. Gates, for the NSTX National Resear.
Princeton Plasma Physics Lab., NJ (US) - Type of Report and Period Covered Note
- Topical;
- Funding Information
- AC02-76CH03073