Measurements of the hydrogenic recombination coefficient for the TFTR vacuum vessel

Conference · Thu Dec 01 04:00:00 EST 1983

OSTI ID:5459566

Dylla, H F; Cecchi, J L; Knize, R J

Characteristic values of the recombination rate coefficient for hydrogen and deuterium in stainless steel have been measured for the inner wall of the TFTR vacuum vessel for vessel temperatures of 25 to 100 C. In situ measurements of k/sub r/ are important for predicting the hydrogen isotope retention in the wall as a function of time, temperature, and discharge exposure, particularly because existing laboratory measurements of k/sub r/ for stainless steel span a range of four orders of magnitude. The measurement technique involved the observation of the decrease in hydrogen pressure during a glow discharge in the TFTR vacuum vessel with an initial static gas fill. The resulting values of k/sub r/ at 25 C are in the range of (0.4 to 4) x 10/sup -27/cm/sup 4/-s/sup -1/ assuming a value of the hydrogenic diffusivity of 2 x 10/sup -12/cm/sup 2/-s/sup -1/ at room temperature. No significant isotopic dependence was observed and the temperature dependence of k/sub r/ is consistent with the literature value (0.5 eV) of the activation energy. The implications of this range of values of k/sub r/, for the estimation of the in-vessel tritium inventory following D-T operation in TFTR are discussed.

• Research Organization: Princeton Univ., NJ (USA). Plasma Physics Lab.
• DOE Contract Number: AC02-76CH03073
• OSTI ID: 5459566
• Report Number(s): PPPL-2046; CONF-830795-7; ON: DE84004296
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700104* -- Fusion Energy-- Plasma Research-- Plasma Kinetics-Experimental-- (-1987)
ALLOYS
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
CHROMIUM ALLOYS
CORROSION RESISTANT ALLOYS
DEUTERIUM
ELECTRIC DISCHARGES
ELEMENTS
FIRST WALL
GLOW DISCHARGES
HYDROGEN
HYDROGEN ISOTOPES
INVENTORIES
IRON ALLOYS
IRON BASE ALLOYS
ISOTOPES
LIGHT NUCLEI
NONMETALS
NUCLEI
ODD-EVEN NUCLEI
ODD-ODD NUCLEI
RADIOISOTOPES
RECOMBINATION
STABLE ISOTOPES
STAINLESS STEELS
STEELS
TFTR REACTORS
THERMONUCLEAR REACTOR WALLS
THERMONUCLEAR REACTORS
TOKAMAK TYPE REACTORS
TRAPPING
TRITIUM
YEARS LIVING RADIOISOTOPES