TFTR experience with D-T operation

Conference · Sat Dec 31 04:00:00 EST 1994

OSTI ID:196837

Meade, D M ^[1]

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1. Princeton Univ., NJ (United States)

Temperatures, densities and confinement of deuterium plasmas confined in tokamaks have been achieved within the last decade that are approaching those required for a D-T reactor. As a result, the unique phenomena present in a D-T reactor plasma (D-T plasma confinement, alpha confinement, alpha heating and possible alpha driven instabilities) can now be studied in the laboratory. Recent experiments on the Tokamak Fusion Test Reactor (TFTR) have been the first magnetic fusion experiments to study plasmas with reactor fuel concentrations of tritium. The injection of {approximately}20 MW of tritium and 10 MW of deuterium neutral beams into the TFTR produced a plasma with a T/D density ratio of {approximately}1 and yielded a fusion power of {approximately}6.2 MW. The fusion power density in the core of the plasma was {approximately}1.4 MW m{sup {minus}3} approximating that expected in a D-T fusion reactor. A TFTR plasma with a T/D density ratio of {approximately}1 was found to have {approximately}20% higher energy confinement time than a comparable D plasma, indicating a confinement scaling with average ion mass, A, of {tau}{sub E}{approximately}A{sup 0.5}. The core ion temperature increased from 27 keV to 35 keV due to a 50% improvement of ion thermal conductivity. Using the electron thermal conductivity from a comparable deuterium plasma, about 50% of the electron temperature increase from 9 keV to 10.6 keV can be attributed to electron heating by the plasma particles. The 5% loss of alpha particles, observed on detectors near the edge of the plasma, was consistent with classical first orbit loss without anomalous effects. Consistent with theoretical calculations, no alpha-driven instabilities of the Toroidal Alfven Eigenmode type were observed by the fluctuation diagnostics. These D-T experiments will continue over a broader range of parameters and higher power levels.

• OSTI ID: 196837
• Report Number(s): CONF-940664--
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
CONFINEMENT TIME
ELECTRON TEMPERATURE
ION TEMPERATURE
OPERATION
PULSED D-T REACTORS
TFTR TOKAMAK