Ex-reactor determination of thermal gap conductance between uranium dioxide and Zircaloy-4. Stage II: high gas pressure
A study of thermal gap conductance (H/sub g/) between depleted UO/sub 2/ and Zircaloy-4 was performed using a transient laser pulse technique under varying conditions of gas pressure (0.1 to 7 MPa), temperature (283 to 673K), gas composition (He, Ar, and He-Xe, He-Ar mixtures) and gap width (5.9 and 23.1 ..mu..m). At fixed gap width, H/sub g/ is dependent upon these variables with the following behavior observed: H/sub g/ exhibits a strong dependence on gas pressure over the range 0.1 to 1 MPa; H/sub g/ decreases with increasing xenon or argon gas concentration at any given temperature and gas pressure; H/sub g/ increases with argon gas pressure over the range 1 to 7 MPa corresponding to the reported increase in argon gas thermal conductivity; and, at a gap of 5.9 ..mu..m, H/sub 2/ exhibits a pronounced hump at gas pressures between 0.1 and 2 MPa for He and He-Xe (90:10) gas mixtures progressively diminishing with decreasing temperature, xenon or argon concentration; and/or increased gap width separation. Comparison of results to predictions based on an ideal expression for thermal gap conductance is made. Gaseous mechanisms of heat transfer under narrow gap conditions are discussed.
- Research Organization:
- Pacific Northwest Lab., Richland, WA (USA)
- DOE Contract Number:
- AC06-76RL01830
- OSTI ID:
- 6029459
- Report Number(s):
- PNL-SA-9582; CONF-8106164-6; ON: TI85004755
- Resource Relation:
- Conference: National Bureau of Standards joint conferences: 8. symposium on thermophysical properties; 17. thermal conductivity conference; 8, Gaithersburg, MD, USA, 15 Jun 1981
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
FUEL-CLADDING INTERACTIONS
HEAT TRANSFER
URANIUM DIOXIDE
ZIRCALOY 4
ARGON
HELIUM
INTERFACES
LASER-RADIATION HEATING
PULSES
XENON
ACTINIDE COMPOUNDS
ALLOYS
CHALCOGENIDES
ELEMENTS
ENERGY TRANSFER
FLUIDS
GASES
HEATING
NONMETALS
OXIDES
OXYGEN COMPOUNDS
PLASMA HEATING
RARE GASES
TIN ALLOYS
URANIUM COMPOUNDS
URANIUM OXIDES
ZIRCALOY
ZIRCONIUM ALLOYS
ZIRCONIUM BASE ALLOYS
220300* - Nuclear Reactor Technology- Fuel Elements