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Title: Direct Observation of IBW Induced Poloidal Flow in TFTR

Abstract

Shearing of the plasma poloidal rotation velocity was observed during application of ion Bernstein wave IBW) power in the Tokamak Fusion Test Reactor (TFTR) tokamak. The first evidence of corroboration between measured poloidal velocity shearing and actively induced Reynolds stress effects is presented. A model reproduces salient experimental features: The observed sheared flow occurs near the tritium fifth harmonic cyclotron resonance layer and depends strongly on the tritium density, in agreement with the model. Furthermore, the model reproduces the observed insensitivity of the induced rotation to the tritium density in the region between the third deuterium harmonic layer and the fifth tritium harmonic layer.

Authors:
; ; ; ; ;
Publication Date:
Research Org.:
Princeton Plasma Physics Laboratory (PPPL), Princeton, NJ
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
2378
Report Number(s):
PPPL-3320
ON: DE00002378
DOE Contract Number:
AC02-76CH03073
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION; TFTR Tokamak; Mathematical Models; Shear; Ion Waves; Flow Stress

Citation Formats

Bell, R.E., Bernabei, S., Hosca, J.C., LeBlanc, B.P., Majeski, R., and et al. Direct Observation of IBW Induced Poloidal Flow in TFTR. United States: N. p., 1998. Web. doi:10.2172/2378.
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Bell, R.E., Bernabei, S., Hosca, J.C., LeBlanc, B.P., Majeski, R., & et al. Direct Observation of IBW Induced Poloidal Flow in TFTR. United States. doi:10.2172/2378.
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Bell, R.E., Bernabei, S., Hosca, J.C., LeBlanc, B.P., Majeski, R., and et al. Sun . "Direct Observation of IBW Induced Poloidal Flow in TFTR". United States. doi:10.2172/2378. https://www.osti.gov/servlets/purl/2378.
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@article{osti_2378,
title = {Direct Observation of IBW Induced Poloidal Flow in TFTR},
author = {Bell, R.E. and Bernabei, S. and Hosca, J.C. and LeBlanc, B.P. and Majeski, R. and et al.},
abstractNote = {Shearing of the plasma poloidal rotation velocity was observed during application of ion Bernstein wave IBW) power in the Tokamak Fusion Test Reactor (TFTR) tokamak. The first evidence of corroboration between measured poloidal velocity shearing and actively induced Reynolds stress effects is presented. A model reproduces salient experimental features: The observed sheared flow occurs near the tritium fifth harmonic cyclotron resonance layer and depends strongly on the tritium density, in agreement with the model. Furthermore, the model reproduces the observed insensitivity of the induced rotation to the tritium density in the region between the third deuterium harmonic layer and the fifth tritium harmonic layer.},
doi = {10.2172/2378},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Sun Nov 01 00:00:00 EST 1998},
month = {Sun Nov 01 00:00:00 EST 1998}
}
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Technical Report:
View Technical Report (0.43 MB)
DOI:  10.2172/2378
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  • ; ; ; ... - Physical Review Letters
    Shearing of the plasma poloidal rotation velocity was observed during application of ion Bernstein wave power in the Tokamak Fusion Test Reactor. The first evidence of corroboration between measured poloidal velocity shearing and actively induced Reynolds stress effects is presented. A model reproduces salient experimental features: The observed sheared flow occurs near the tritium fifth harmonic cyclotron resonance layer and depends strongly on the tritium density in agreement with the model. Furthermore, the model reproduces the observed insensitivity of the induced rotation to the tritium density in the region between the third deuterium harmonic layer and the fifth tritium harmonicmore » layer. {copyright} {ital 1999} {ital The American Physical Society}« less

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  • ; ; ; ...
    Impurity poloidal rotation velocities have been measured in the core of TFTR plasmas using a new spectroscopic diagnostic. Two types of transitions to enhanced confinement in reversed shear plasmas are examined. A bifurcation in carbon poloidal rotation is observed to occur before the transition to enhanced confinement for one of these types, while other measured plasmas parameters remain constant. A narrow radial region with reversed poloidal rotation and rotational shear is established 60-100 ms before the transition, and is associated with a large negative radial electric field.

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    Deuterium-tritium plasmas with enhanced energy confinement and stability have been produced in the high poloidal beta, advanced tokamak regime in TFTR. Confinement enhancement H {triple_bond} {tau}{sub E}/{tau}{sub E ITER-89P} > 4 has been obtained in a limiter H-mode configuration at moderate plasma current I{sub p} = 0.85 {minus} 1.46 MA. By peaking the plasma current profile, {beta}{sub N dia} {triple_bond} 10{sup 8} < {beta}{sub t{perpendicular}} > aB{sub 0}/I{sub p} = 3 has been obtained in these plasma,s exceeding the {beta}{sub N} limit for TFTR plasmas with lower internal inductance, l{sub i}. Fusion power exceeding 6.7 MW with a fusion powermore » gain Q{sub DT} = 0.22 has been produced with reduced alpha particle first orbit loss provided by the increased l{sub i}.« less

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