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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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No impact from Savannah River radioactive wasps
The news is abuzz with recent news stories about four radioactive wasp nests found at the Department of Energy’s Savannah River Site in South Carolina. The site has been undergoing cleanup operations since the 1990s related to the production of plutonium and tritium for defense purposes during the Cold War. Cleanup activities are expected to continue into the 2060s.
Yoshio Watari
Nuclear Science and Engineering | Volume 103 | Number 2 | October 1989 | Pages 166-181
Technical Paper | doi.org/10.13182/NSE89-A28505
Articles are hosted by Taylor and Francis Online.
The reactor physics problems in core designs for high-burnup and long-operating-cycle length are clarified. Two core concepts are proposed to deal with these problems: 1. the advanced homogeneous core (A-HOC) in which the power distribution is flattened by dividing the core into two regions with different fuel volume fractions 2. the advanced axial heterogeneous core (A-AHC) in which a thin internal blanket is introduced at the core midplane in the inner core region of the A-HOC. Core performance parameters such as fissile inventory, breeding ratio, and power and flux distributions are evaluated in detail by discrete burnup analyses. The results show that the A-AHC has more uniform power and flux distributions and a more stable power shape than the A-HOC, and the A-AHC seems to be a good candidate for achieving high-burnup and long-operating-cycle length.