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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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New coolants, new fuels: A new generation of university reactors
Here’s an easy way to make aging U.S. power reactors look relatively youthful: Compare them (average age: 43) with the nation’s university research reactors. The 25 operating today have been licensed for an average of about 58 years.
H. Carlsen, D. N. Sah
Nuclear Technology | Volume 55 | Number 3 | December 1981 | Pages 587-593
Technical Paper | Nuclear Fuel | doi.org/10.13182/NT81-A32803
Articles are hosted by Taylor and Francis Online.
The distribution of 239Pu formed in uranium dioxide during irradiation is nonuniform and changes with burnup. This implicates a burnup effect on the fuel temperature distribution. The total 239Pu concentration during irradiation and its radial distribution at end-of-life has been calculated in low-enriched UO2 fuel pellets. The processes considered are 239Pu buildup by capture of thermal and resonance neutrons and 239Pu loss by thermal fissions and neutron capture. The calculated total 239Pu content is verified by chemical analysis, and the calculated 239Pu profile by comparison with results from quantitative alpha autoradiography for two fuel specimens. The effect of a nonuniform radial 239Pu distribution on the fuel temperature profile is evaluated. At a burnup level of 3560 GJ/kg U and a linear heat rating of 50 kW/m, the centerline temperature is calculated to be 245 K lower than that calculated on the assumption that the 239Pu is distributed uniformly.
