Tritium permeation and wall loading in the TFTR vacuum vessel

Journal Article · Mon Jan 01 00:00:00 EST 1979 · J. Vac. Sci. Technol.; (United States)

DOI:https://doi.org/10.1116/1.569868· OSTI ID:6381093

Cecchi, J L

The problems of tritium permeation through and loading of the TFTR vacuum vessel wall structural components are considered for various TFTR operating scenarios and outgassing modes. A general analytical solution to the time-dependent diffusion equation which takes into account the boundary conditions arising from the tritium filling gas as well as the source function associated with implanted energetic charge exchange tritium is presented. Expressions are derived for two quantities of interest: (1) the total amount of tritium leaving the outer surface of a particular vessel component as a function of time, and (2) the amount retained as a function of time. These quantities are evaluated for specific TFTR cases. The results are that permeation through the vessel is important only for the bellows during discharge cleaning if the wall temperature rises above approx.150 /sup 0/C. At 250 /sup 0/C, after 72 hours of discharge cleaning approx.200 Ci would be lost. The wall loading is most severe in the stainless-steel plate sections during normal pulsed operation where approx.600 Ci would be retained after 1000 shots if the walls were at 20 /sup 0/C. Maintaining the temperature of the walls above 100 /sup 0/C greatly lessens the problem. The 600 Ci in the wall would be reduced to approx.10 Ci if the wall were heated to 250 /sup 0/C for about 60 h.

• Research Organization: Plasma Physics Laboratory, Princeton University, Princeton, New Jersey 08540
• OSTI ID: 6381093
• Journal Information: J. Vac. Sci. Technol.; (United States), Vol. 16:1
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
TFTR REACTORS
CONTAINERS
DEGASSING
BOUNDARY CONDITIONS
FICK LAWS
GASEOUS DIFFUSION
HIGH TEMPERATURE
INTEGRAL EQUATIONS
MATHEMATICAL MODELS
OXIDES
STAINLESS STEELS
STEADY-STATE CONDITIONS
TRITIUM
VAPOR PRESSURE
ALLOYS
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
CHALCOGENIDES
CHROMIUM ALLOYS
CORROSION RESISTANT ALLOYS
DIFFUSION
EQUATIONS
HYDROGEN ISOTOPES
IRON ALLOYS
IRON BASE ALLOYS
ISOTOPES
LIGHT NUCLEI
NUCLEI
ODD-EVEN NUCLEI
OXYGEN COMPOUNDS
PHYSICAL PROPERTIES
RADIOISOTOPES
STEELS
THERMODYNAMIC PROPERTIES
THERMONUCLEAR REACTORS
TOKAMAK TYPE REACTORS
YEARS LIVING RADIOISOTOPES
700206* - Fusion Power Plant Technology- Environmental Aspects