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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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Hash Hashemian: Visionary leadership
As Dr. Hashem M. “Hash” Hashemian prepares to step into his term as President of the American Nuclear Society, he is clear that he wants to make the most of this unique moment.
A groundswell in public approval of nuclear is finding a home in growing governmental support that is backed by a tailwind of technological innovation. “Now is a good time to be in nuclear,” Hashemian said, as he explained the criticality of this moment and what he hoped to accomplish as president.
Yunzhao Li, Hongchun Wu, Liangzhi Cao
Nuclear Science and Engineering | Volume 174 | Number 2 | June 2013 | Pages 163-171
Technical Paper | doi.org/10.13182/NSE11-111
Articles are hosted by Taylor and Francis Online.
The isotropic simplified spherical harmonics (SP3) method is employed to cast the neutron transport equation into a coupled set of two equations each of which shares identical mathematical form with the neutron diffusion equation. An exponential function expansion nodal (EFEN) method is presented for an arbitrary triangular grid and implemented to solve the coupled SP3 equations. The EFEN method couples adjacent nodes by defining partial currents on each interface and expanding the detailed flux distribution within each node into a sum of exponential functions to obtain a response matrix between the incoming and outgoing partial currents and a neutron balance condition for each node to obtain the nodal average flux. Numerical results demonstrate that both keff and power distributions agree well with other codes. We find comparable accuracy in most situations, and the new method appears to be faster than the other codes even in cases where EFEN requires a finer unstructured mesh.
