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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.
Ken Nakajima, Masanori Akai, Takenori Suzaki
Nuclear Science and Engineering | Volume 116 | Number 2 | February 1994 | Pages 138-146
Technical Paper | doi.org/10.13182/NSE94-A21489
Articles are hosted by Taylor and Francis Online.
The modified conversion ratio is defined as the ratio of 238U captures to total fission. Gamma-ray spectrometry of irradiated fuel rods has been introduced to measure this quantity in two types of water-moderated low-enriched UO2 cores: the standard core, called the 1.42S core, and a tight-lattice core, called the 0.56S core. The water moderator-to-fuel volume ratios Vm/Vf of the cores are 1.420 and 0.564, respectively. As no activation foil is used in this method, no corrections are needed for the neutron self-shielding and neutron flux depression that are caused by such a foil. Instead, the gamma-ray self-shielding effect due to the fuel rod must be corrected. The modified conversion ratio is measured by this method are 0.457 for the 1.42S core and 0.724 for the 0.56S core. The errors in the experimental results are estimated to be∼3%. Computer analyses using the VIM continuous-energy Monte Carlo code with the JENDL-2 library show that the calculated value is ∼6% larger than the experimental one for the tight-lattice 0.56S core.
