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Title: Gyrokinetic Calculations of Microinstabilities and Transport During RF H-Modes on Alcator C-Mod

Abstract

Physics understanding for the experimental improvement of particle and energy confinement is being advanced through massively parallel calculations of microturbulence for simulated plasma conditions. The ultimate goal, an experimentally validated, global, non-local, fully nonlinear calculation of plasma microturbulence is still not within reach, but extraordinary progress has been achieved in understanding microturbulence, driving forces and the plasma response in recent years. In this paper we discuss gyrokinetic simulations of plasma turbulence being carried out to examine a reproducible, H-mode, RF heated experiment on the Alcator CMOD tokamak3, which exhibits an internal transport barrier (ITB). This off axis RF case represents the early phase of a very interesting dual frequency RF experiment, which shows density control with central RF heating later in the discharge. The ITB exhibits steep, spontaneous density peaking: a reduction in particle transport occurring without a central particle source. Since the central temperature is maintained while the central density is increasing, this also suggests a thermal transport barrier exists. TRANSP analysis shows that ceff drops inside the ITB. Sawtooth heat pulse analysis also shows a localized thermal transport barrier. For this ICRF EDA H-mode, the minority resonance is at r/a * 0.5 on the high field side. Theremore » is a normal shear profile, with q monotonic.« less

Authors:
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Publication Date:
Research Org.:
Princeton Plasma Physics Lab., NJ (US)
Sponsoring Org.:
USDOE Office of Science (US)
OSTI Identifier:
798196
Report Number(s):
PPPL-3707.pdf
TRN: US0202153
DOE Contract Number:  
AC02-76CH03073
Resource Type:
Technical Report
Resource Relation:
Other Information: PBD: 18 Jun 2002
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; CONFINEMENT; HEATING; PARTICLE SOURCES; PHYSICS; PLASMA; RESONANCE; SHEAR; TRANSPORT; TURBULENCE

Citation Formats

M.H. Redi, C. Fiore, P. Bonoli, C. Bourdelle, R. Budny, W.D. Dorland, D. Ernst, G. Hammett, D. Mikkelsen, J. Rice, and S. Wukitch. Gyrokinetic Calculations of Microinstabilities and Transport During RF H-Modes on Alcator C-Mod. United States: N. p., 2002. Web. doi:10.2172/798196.
M.H. Redi, C. Fiore, P. Bonoli, C. Bourdelle, R. Budny, W.D. Dorland, D. Ernst, G. Hammett, D. Mikkelsen, J. Rice, & S. Wukitch. Gyrokinetic Calculations of Microinstabilities and Transport During RF H-Modes on Alcator C-Mod. United States. doi:10.2172/798196.
M.H. Redi, C. Fiore, P. Bonoli, C. Bourdelle, R. Budny, W.D. Dorland, D. Ernst, G. Hammett, D. Mikkelsen, J. Rice, and S. Wukitch. Tue . "Gyrokinetic Calculations of Microinstabilities and Transport During RF H-Modes on Alcator C-Mod". United States. doi:10.2172/798196. https://www.osti.gov/servlets/purl/798196.
@article{osti_798196,
title = {Gyrokinetic Calculations of Microinstabilities and Transport During RF H-Modes on Alcator C-Mod},
author = {M.H. Redi and C. Fiore and P. Bonoli and C. Bourdelle and R. Budny and W.D. Dorland and D. Ernst and G. Hammett and D. Mikkelsen and J. Rice and S. Wukitch},
abstractNote = {Physics understanding for the experimental improvement of particle and energy confinement is being advanced through massively parallel calculations of microturbulence for simulated plasma conditions. The ultimate goal, an experimentally validated, global, non-local, fully nonlinear calculation of plasma microturbulence is still not within reach, but extraordinary progress has been achieved in understanding microturbulence, driving forces and the plasma response in recent years. In this paper we discuss gyrokinetic simulations of plasma turbulence being carried out to examine a reproducible, H-mode, RF heated experiment on the Alcator CMOD tokamak3, which exhibits an internal transport barrier (ITB). This off axis RF case represents the early phase of a very interesting dual frequency RF experiment, which shows density control with central RF heating later in the discharge. The ITB exhibits steep, spontaneous density peaking: a reduction in particle transport occurring without a central particle source. Since the central temperature is maintained while the central density is increasing, this also suggests a thermal transport barrier exists. TRANSP analysis shows that ceff drops inside the ITB. Sawtooth heat pulse analysis also shows a localized thermal transport barrier. For this ICRF EDA H-mode, the minority resonance is at r/a * 0.5 on the high field side. There is a normal shear profile, with q monotonic.},
doi = {10.2172/798196},
journal = {},
number = ,
volume = ,
place = {United States},
year = {2002},
month = {6}
}