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Conference Spotlight
2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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Leading the charge: INL’s role in advancing HALEU production
Idaho National Laboratory is playing a key role in helping the U.S. Department of Energy meet near-term needs by recovering HALEU from federal inventories, providing critical support to help lay the foundation for a future commercial HALEU supply chain. INL also supports coordination of broader DOE efforts, from material recovery at the Savannah River Site in South Carolina to commercial enrichment initiatives.
Motoo Aoyama and Sadao Uchikawa
Nuclear Science and Engineering | Volume 92 | Number 1 | January 1986 | Pages 42-50
Technical Paper | doi.org/10.13182/NSE86-A17863
Articles are hosted by Taylor and Francis Online.
A new method for solving the neutron diffusion equations in multiconnected regions with arbitrarily shaped boundaries has been developed by using a compound boundary-fitted coordinate transformation. In the compound boundary-fitted coordinate transformation, inner regions and an outer region in the physical plane are transformed by different coordinate systems. The neutron diffusion equations obtained by the coordinate transformation are solved in the rectangular coordinate system for the outer region, and in the cylindrical coordinate system for the inner regions, so that the boundary conditions are represented accurately and detailed calculations in a particular region can be performed without increasing the number of grid points in other regions.