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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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Powering the future: How the DOE is fueling nuclear fuel cycle research and development
As global interest in nuclear energy surges, the United States must remain at the forefront of research and development to ensure national energy security, advance nuclear technologies, and promote international cooperation on safety and nonproliferation. A crucial step in achieving this is analyzing how funding and resources are allocated to better understand how to direct future research and development. The Department of Energy has spearheaded this effort by funding hundreds of research projects across the country through the Nuclear Energy University Program (NEUP). This initiative has empowered dozens of universities to collaborate toward a nuclear-friendly future.
E. A. Fischer
Nuclear Science and Engineering | Volume 78 | Number 3 | July 1981 | Pages 227-238
Technical Paper | doi.org/10.13182/NSE81-A20300
Articles are hosted by Taylor and Francis Online.
An approximate method to calculate the parallel neutron leakage in fast reactor slab lattices is described. It is derived from the integral transport equation and assumes isotropic scattering. By using an expansion in terms of oscillating functions, rather than the usual power series expansion in the buckling, it is proven that the method is also valid for voided cells. Results for a two-region cell are presented; they confirm that the widely used Benoist equation is valid for cases when sodium is present. However, for voided or nearly voided cells, the Benoist equation fails, whereas the new method is valid for any cell composition. The same method is applied to find the effective diffusion coefficient for a low-density channel. In the limit of zero buckling, the method reduces to well-known results available in literature by Rowlands. However, the buckling correction, obtained by a consistent expansion of the integral transport equation, is different from similar corrections in the literature.