Published December 10, 2015 | Version v1
Journal article Metadata-only

Impact of central ECCD on steady-state hybrid scenario in DIII-D

Creators

  • 1. General Atomics, P.O. Box 85608, San Diego, CA (United States)
  • 2. Princeton Plasma Physics Laboratory, Princeton, NJ (United States)
  • 3. Princeton University, Princeton, NJ (United States)
  • 4. University of Wisconsin - Madison, Madison, WI (United States)
  • 5. Columbia University, New York, NY (United States)

Description

"Steady-state" hybrid plasmas in DIII-D with zero surface loop voltage have been maintained for up to two current relaxation times using 3.4 MW of central electron cyclotron current drive (ECCD). In addition to driving ≈0.2 MA of plasma current, central ECCD leads to significant changes in Alfvén eigenmode (AE) activity and thermal transport. For neutral-beam-only heating, strong AE activity is observed that causes a ∼35% degradation in the neutron rate. With central ECCD this AE activity is suppressed, replaced by a bursty energetic particle mode that appears more benign as the neutron rate is closer to the classical value. The electron thermal diffusivity increases by ≈50% for 2.4 MW of ECCD compared to neutral-beam-only cases. Fortunately, the global thermal confinement factor remains the same (H98y2=1.4) as the higher thermal transport for PEC=2.4 MW hybrids is offset by the decreased fast ion transport resulting from AE suppression

Additional details

Identifiers

DOI
10.1063/1.4936539;

Publishing Information

Journal Title
AIP Conference Proceedings
Journal Volume
1689
Journal Issue
1
Journal Page Range
p. 090002-090002.4
ISSN
0094-243X
CODEN
APCPCS

Conference

Title
21. topical conference on radio frequency power in plasmas
Dates
27-29 Apr 2015
Place
Lake Arrowhead, CA (United States)

INIS

Country of Publication
United States
Country of Input or Organization
International Atomic Energy Agency (IAEA)
INIS RN
47066430
Subject category
S71: CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS;
Resource subtype / Literary indicator
Conference
Descriptors DEI
ALFVEN WAVES; BEAMS; COMPARATIVE EVALUATIONS; DOUBLET-3 DEVICE; ECR CURRENT DRIVE; EIGENFREQUENCY; ELECTRIC CURRENTS; ELECTRIC POTENTIAL; ELECTRONS; HEAT TRANSFER; ICR HEATING; INHIBITION; NEUTRONS; PARTICLES; PLASMA; STEADY-STATE CONDITIONS; THERMAL DIFFUSIVITY
Descriptors DEC
BARYONS; CLOSED PLASMA DEVICES; CURRENTS; ELEMENTARY PARTICLES; ENERGY TRANSFER; EVALUATION; FERMIONS; HADRONS; HEATING; HIGH-FREQUENCY HEATING; HYDROMAGNETIC WAVES; LEPTONS; NON-INDUCTIVE CURRENT DRIVE; NUCLEONS; PHYSICAL PROPERTIES; PLASMA HEATING; THERMODYNAMIC PROPERTIES; THERMONUCLEAR DEVICES; TOKAMAK DEVICES

Optional Information

Notes
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