The effects of exchange gas temperature and pressure on the beta-layering process in solid deuterium-tritium fusion fuel

Conference · Mon Jan 01 04:00:00 EST 1990

DOI:https://doi.org/10.1016/S0921-4526(90)80931-8· OSTI ID:6934901

Hoffer, J K; Foreman, L R ^[1]; Simpson, J D; Pattinson, T R ^[2]

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1. Los Alamos National Lab., NM (USA)
2. KMS Fusion, Inc., Ann Arbor, MI (USA)

It has recently been shown that when solid tritium is confined in an isothermal enclosure, self-heating due to beta decay drives a net sublimation of material from thick, warmer layers to thin, cooler ones, ultimately resulting in layer thickness uniformity. We have observed this process of beta-layering'' in a 50--50 D-T mixture in both cylindrical and spherical enclosures at temperatures from 19.6 K, down to 11.6 K. The measured time constants are found to depend on the {sup 3}He content as suggested by recent theoretical predictions. When using an enclosure having low thermal conductivity, the ultimate layer uniformity is found to be a strong function of the exchange gas pressure. This is due to the presence of thermal convection in the exchange gas and consequent temperature anisotropy at the solid layer surface. 6 refs., 2 figs., 1 tab.

• Research Organization: Los Alamos National Lab., NM (USA)
• Sponsoring Organization: DOE/DP
• DOE Contract Number: W-7405-ENG-36
• OSTI ID: 6934901
• Report Number(s): LA-UR-90-850; CONF-900806--4; ON: DE90009015
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700209* -- Fusion Power Plant Technology-- Component Development & Materials Testing
BETA DECAY
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BOUNDARY LAYERS
DECAY
DEUTERIUM
FUELS
HYDROGEN ISOTOPES
ISOTOPES
LAYERS
LIGHT NUCLEI
NUCLEAR DECAY
NUCLEI
ODD-EVEN NUCLEI
ODD-ODD NUCLEI
PHYSICAL PROPERTIES
PRESSURE EFFECTS
RADIOISOTOPES
STABLE ISOTOPES
TEMPERATURE EFFECTS
THERMAL CONDUCTIVITY
THERMODYNAMIC PROPERTIES
THERMONUCLEAR FUELS
TRITIUM
YEARS LIVING RADIOISOTOPES