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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.
Alain Hébert
Nuclear Science and Engineering | Volume 169 | Number 1 | September 2011 | Pages 81-97
Technical Note | doi.org/10.13182/NSE10-39
Articles are hosted by Taylor and Francis Online.
We are investigating a new class of linear characteristics schemes along finite-length tracks for solving the transport equation for neutral particles with scattering anisotropy. These algorithms are based on diamond differencing, as implemented with the method of discrete ordinates. The quadratic-order diamond-differencing (DD1) scheme is based on linear discontinuous coefficients that are derived through the application of approximations describing the mesh-averaged spatial flux moments in terms of spatial source moments and of the beginning- and end-of-segment flux values. This DD1 linear characteristics scheme is inherently conservative. This approach is an improvement relative to other linear characteristics schemes because no information needs to be collected on internal surfaces. Consequently, the DD1 scheme is compatible with existing tracking files for the collision-probability method. The proposed scheme is verified in one-dimensional slab geometry where it is found to be equivalent to a discrete ordinates solution and on simple two-dimensional benchmarks made of regular squares or hexagons.