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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.
G. C. Pomraning
Nuclear Science and Engineering | Volume 136 | Number 1 | September 2000 | Pages 1-14
Technical Paper | doi.org/10.13182/NSE00-A2144
Articles are hosted by Taylor and Francis Online.
We consider the energy-dependent pencil beam problem for a thin slab with screened Rutherford scattering. Under certain approximations, this problem can be reduced to a monoenergetic problem with an effective depth-dependent scattering cross section [overbar]s(z). The z dependence of this cross section arises from the explicit z dependence of the true scattering cross section s(z,E), as well as from an induced z dependence associated with the energy dependence of s(z,E). Prior work led to a quadrature result for the scalar flux in the special case that [overbar]s is a constant, independent of z. In this paper, we generalize this result by allowing [overbar]s(z) to have an arbitrary z dependence. We use these considerations to show that simple homogenization, namely, replacing [overbar]s(z) by its average over the slab, can lead to significant errors in the scalar flux. A more detailed homogenization algorithm is suggested, involving an effective screening parameter in the screened Rutherford scattering phase function, as well as an effective depth coordinate z.