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General Matter to build Kentucky enrichment plant under DOE lease
The Department of Energy’s Office of Environmental Management announced it has signed a lease with General Matter for the reuse of a 100-acre parcel of federal land at the former Paducah Gaseous Diffusion Plant in Kentucky for a new private-sector domestic uranium enrichment facility.
Anil Kumar
Nuclear Science and Engineering | Volume 82 | Number 3 | December 1982 | Pages 354-358
Technical Note | doi.org/10.13182/NSE82-A19396
Articles are hosted by Taylor and Francis Online.
In the considerations of recriticality of molten fuel assemblies, the presence of bubbles in the fuel plays an important role. In such a situation, there are two opposing contributions to reactivity from (a) the phenomenon of neutron streaming in bubbles (negative contribution) and (b) the phenomenon of changing neutron self-multiplication in the fuel (positive contribution). It is not possible to accurately calculate the individual reactivity contributions of the two phenomena using multidimensional transport theory or Monte Carlo codes. A simple diffusion theory expression given by Nicholson and Goldsmith for estimating reactivity contribution due to neutron streaming alone has been used extensively. As a part of the present contribution, first an attempt has been made to improve the applicability of the Nicholson-Goldsmith work by expressing extrapolation length in terms of the root-mean-square free path in the assembly. It is found that the application of the Trombay criticality formula, particularly its “modified Wigner rational variant,” leads to an expression for bubble reactivity worth, due to neutron streaming alone, that yields the closest agreement with the bubble worth values computed from the two-dimensional transport theory code TWOTRAN and the Monte Carlo code KENO.