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Title: Comparison of Theory with Rotation Measurements in JET ICRH Plasmas

Abstract

Plasma rotation appears to improve plasma performance by increasing the E x B flow shearing rate, thus decreasing radial correlations in the microturbulence. Also, plasma rotation can increase the stability to resistive MHD modes. In the Joint European Torus (JET), toroidal rotation rates omega (subscript ''tor'') with high Mach numbers are generally measured in NBI-heated plasmas (since the neutral beams aim in the co-plasma current direction). They are considerably lower with only ICRH (and Ohmic) heating, but still surprisingly large considering that ICRH appears to inject relatively small amounts of angular momentum. Either the applied torques are larger than naively expected, or the anomalous transport of angular momentum is smaller than expected. Since ICRH is one of the main candidates for heating next-step tokamaks, and for creating burning plasmas in future tokamak reactors, this paper attempts to understand ICRH-induced plasma rotation.

Authors:
; ; ; ; ; ; ; ; ;
Publication Date:
Research Org.:
Princeton Plasma Physics Lab., Princeton, NJ (US)
Sponsoring Org.:
USDOE Office of Energy Research (ER) (US)
OSTI Identifier:
787685
Report Number(s):
PPPL-3585
TRN: US0109451
DOE Contract Number:
AC02-76CH03073
Resource Type:
Technical Report
Resource Relation:
Other Information: PBD: 27 Jun 2001
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; ANGULAR MOMENTUM; ICR HEATING; MACH NUMBER; PERFORMANCE; PLASMA WAVES; ROTATION; TORI

Citation Formats

R.V. Budny, C.S. Chang, C. Giroud, R.J. Goldston, D. McCune, J. Ongena, F.W. Perkins, R.B. White, K.-D. Zastrow, and and contributors to the EFDA-JET work programme. Comparison of Theory with Rotation Measurements in JET ICRH Plasmas. United States: N. p., 2001. Web. doi:10.2172/787685.
R.V. Budny, C.S. Chang, C. Giroud, R.J. Goldston, D. McCune, J. Ongena, F.W. Perkins, R.B. White, K.-D. Zastrow, & and contributors to the EFDA-JET work programme. Comparison of Theory with Rotation Measurements in JET ICRH Plasmas. United States. doi:10.2172/787685.
R.V. Budny, C.S. Chang, C. Giroud, R.J. Goldston, D. McCune, J. Ongena, F.W. Perkins, R.B. White, K.-D. Zastrow, and and contributors to the EFDA-JET work programme. Wed . "Comparison of Theory with Rotation Measurements in JET ICRH Plasmas". United States. doi:10.2172/787685. https://www.osti.gov/servlets/purl/787685.
@article{osti_787685,
title = {Comparison of Theory with Rotation Measurements in JET ICRH Plasmas},
author = {R.V. Budny and C.S. Chang and C. Giroud and R.J. Goldston and D. McCune and J. Ongena and F.W. Perkins and R.B. White and K.-D. Zastrow and and contributors to the EFDA-JET work programme},
abstractNote = {Plasma rotation appears to improve plasma performance by increasing the E x B flow shearing rate, thus decreasing radial correlations in the microturbulence. Also, plasma rotation can increase the stability to resistive MHD modes. In the Joint European Torus (JET), toroidal rotation rates omega (subscript ''tor'') with high Mach numbers are generally measured in NBI-heated plasmas (since the neutral beams aim in the co-plasma current direction). They are considerably lower with only ICRH (and Ohmic) heating, but still surprisingly large considering that ICRH appears to inject relatively small amounts of angular momentum. Either the applied torques are larger than naively expected, or the anomalous transport of angular momentum is smaller than expected. Since ICRH is one of the main candidates for heating next-step tokamaks, and for creating burning plasmas in future tokamak reactors, this paper attempts to understand ICRH-induced plasma rotation.},
doi = {10.2172/787685},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Wed Jun 27 00:00:00 EDT 2001},
month = {Wed Jun 27 00:00:00 EDT 2001}
}

Technical Report:

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  • A nonperturbative code NOVA-KN (Kinetic Nonperturbative) has been developed to account for finite orbit width (FOW) effects in nonperturbative resonant modes such as the low-frequency MHD modes observed in the Joint European Torus (JET). The NOVA-KN code was used to show that the resonant modes with frequencies in the observed frequency range are ones having the characteristic toroidal precession frequency of H-minority ions. Results are similar to previous theoretical studies of fishbone instabilities, which were found to exist at characteristic precession frequencies of hot ions.
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