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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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ANS joins others in seeking to discuss SNF/HLW impasse
The American Nuclear Society joined seven other organizations to send a letter to Energy Secretary Christopher Wright on July 8, asking to meet with him to discuss “the restoration of a highly functioning program to meet DOE’s legal responsibility to manage and dispose of the nation’s commercial and legacy defense spent nuclear fuel (SNF) and high-level radioactive waste (HLW).”
Ryan G. McClarren, James Paul Holloway
Nuclear Science and Engineering | Volume 159 | Number 3 | July 2008 | Pages 330-337
Technical Note | doi.org/10.13182/NSE159-330
Articles are hosted by Taylor and Francis Online.
We present an extension of our quasi-linear numerical method for the time-dependent spherical harmonics (Pn) equations. The extension involves adding time integration that is higher order than backward Euler, yet avoids artificial oscillations in the solution. This new approach mimics that of our previously presented quasi-linear spatial scheme in that we use a first-order step to determine in which parts of the problem we can use a high-order method. The first-order scheme we use for time integration is backward Euler, and the high-order method we implement is Crank-Nicolson. Results are presented that demonstrate the effectiveness and necessity of this approach.