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May 31–June 3, 2026
Denver, CO|Sheraton Denver
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Modernizing I&C for operations and maintenance, one phase at a time
The two reactors at Dominion Energy’s Surry plant are among the oldest in the U.S. nuclear fleet. Yet when the plant celebrated its 50th anniversary in 2023, staff could raise a toast to the future. Surry was one of the first plants to file a subsequent license renewal (SLR) application, and in May 2021, it became official: the plant was licensed to operate for a full 80 years, extending its reactors’ lifespans into 2052 and 2053.
S. Van Criekingen, E. E. Lewis, R. Beauwens
Nuclear Science and Engineering | Volume 152 | Number 2 | February 2006 | Pages 149-163
Technical Paper | doi.org/10.13182/NSE06-1
Articles are hosted by Taylor and Francis Online.
A mixed-hybrid treatment of the spatial variables of the within-group neutron transport equation generalizes existing mixed and hybrid methods, combining their attractive features: the simultaneous approximation of even- and odd-parity angular flux components and the use of Lagrange multipliers to enforce interface continuity. A finite element spatial discretization and spherical harmonic angular expansions are used. We discuss rank conditions for the proposed methods and provide a new derivation of the Rumyantsev interface conditions. Even- and odd-parity interface continuity properties corresponding to these Rumyantsev conditions are established. We examine inclusion conditions and the interaction of the primal/dual distinction due to the spatial variable with the even/odd-order spherical harmonic approximation distinction due to the angular variable. Numerical solutions for both even- and odd-order spherical harmonic approximations are presented, and a promising enclosing property is observed in our results.