Journal article
The D-COM Blind Problem on Fission Gas Release: The Predictions of the TRANSURANUS and FUTURE Codes
The concentration of retained xenon, the percentage of porosity and the UO2 grain size have been measured as a function of radial position in the base irradiated rod AG11-8 and the transient tested rod AG11-10. In the base irradiation, densification of the fuel took place and slight grain growth occurred at the pellet centre.
Gas release was not detected. During the transient test, 15–20% of the xenon inventory was released from the fuel grains. Gas release was accompanied in the central region of the fuel by an increase in the porosity from 4.7 to 6–8%. These findings are compared with the predictions made by the fuel performance code TRANSURANUS.
The code predictions are in good agreement with the experimental observations. FUTURE was used to investigate the development of gas bubbles and the mechanisms controlling gas release in the rods during the base irradiation and the transient test. According to FUTURE fission gas will have accumulated on the grain boundaries during the base irradiation.
The code indicates that variations in the fuel microstructure resulting from the base irradiation will have caused the level of gas release to vary along the fuel stack in rods AG11-9 and AG11-10 during the transient test. FUTURE also suggests that fission induced bubble re-solution became increasingly important for release during the latter stages of the transient test.
Moreover, the code calculations imply that bubble migration could have played a significant role in the release process.
Language: | English |
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Year: | 1989 |
Pages: | 211-233 |
ISSN: | 1872759x and 00295493 |
Types: | Journal article |
DOI: | 10.1016/0029-5493(89)90172-6 |
ORCIDs: | Mogensen, Mogens Bjerg |