Fast-wave ion cyclotron resonance heating experiments on the Alcator C tokamak

Journal Article · Mon Jul 01 04:00:00 EDT 1991 · Physics of Fluids B; (USA)

DOI:https://doi.org/10.1063/1.859686· OSTI ID:5588760

Shepard, T D; Fiore, C L; McDermott, F S; Parker, R R; Porkolab, M ^[1]

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1. Plasma Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (USA)

In this paper, minority regime fast-wave ICRF (Ion cyclotron range of frequency) heating experiments conducted on the Alcator C tokamak (Nucl. Fusion {bold 26}, 1665 (1986)) are described. Up to 450 kW of rf (radio frequency) power at frequency {ital f}=180 MHz was injected into plasmas composed of deuterium majority and hydrogen minority ion species at magnetic fields of {ital B}{sub 0}{congruent}12 T, densities 0.8{le}{ital {bar n}}{sub {ital e}}{le}5{times}10{sup 20} m{sup {minus}3}, and minority concentrations 0.25{approx lt}{eta}{sub H}{le}8%. Typical ion temperatures were {ital T}{sub D}(0){similar to}1 keV, while, depending on density, typical electron temperatures were in the range {ital T}{sub {ital e}}(0){similar to}1.5--2.5 keV. Central deuterium ion temperature increases of {Delta}{ital T}{sub D}(0)=400 eV were observed at {ital {bar n}}{sub {ital e}}=1{times}10{sup 20} m{sup {minus}3}, while significantly smaller ion temperature increases were observed at higher densities. At the highest densities, ion heating became insignificant due in part to a limitation on power handling by the antenna that became more severe with increasing density. Significant electron heating was not observed at any density. Heating of the minority species at low densities indicated severe losses, but at higher densities it was consistent with efficient collisional coupling of the rf power from the hydrogen minority species to the deuterium majority species. Analysis of the deuterium power balance indicated no significant change in the deuterium thermal transport properties as a function of rf power. This may be consistent with the fact that the rf power never exceeded the Ohmic heating (OH) contribution. However, a very strong dependence of the deuterium transport properties on density was observed, and appears to be the dominant process limiting the effectiveness of ICRF heating at high density.

• DOE Contract Number: AC02-78ET51013
• OSTI ID: 5588760
• Journal Information: Physics of Fluids B; (USA), Journal Name: Physics of Fluids B; (USA) Vol. 3:7; ISSN PFBPE; ISSN 0899-8221
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700101* -- Fusion Energy-- Plasma Research-- Confinement
Heating
& Production
ALCATOR DEVICE
AUXILIARY HEATING
CLOSED PLASMA DEVICES
COLLISIONAL PLASMA
COUPLING
DEUTERIUM
ELECTROMAGNETIC RADIATION
ELECTRON TEMPERATURE
ELEMENTS
ENERGY TRANSFER
FREQUENCY RANGE
HEAT TRANSFER
HEATING
HIGH-FREQUENCY HEATING
HYDROGEN
HYDROGEN ISOTOPES
ICR HEATING
ION TEMPERATURE
ISOTOPES
LIGHT NUCLEI
MAGNETIC FIELDS
MHZ RANGE
MHZ RANGE 100-1000
NONMETALS
NUCLEI
ODD-ODD NUCLEI
PLASMA
PLASMA HEATING
RADIATIONS
RADIOWAVE RADIATION
SPACE HEATING
STABLE ISOTOPES
THERMAL CONDUCTION
THERMONUCLEAR DEVICES
TOKAMAK DEVICES