ANS is committed to advancing, fostering, and promoting the development and application of nuclear sciences and technologies to benefit society.
Explore the many uses for nuclear science and its impact on energy, the environment, healthcare, food, and more.
Explore membership for yourself or for your organization.
Conference Spotlight
2026 Nuclear Energy Conference & Expo (NECX)
August 24–27, 2026
Dallas, TX|Hilton Anatole
Latest Magazine Issues
Jul 2026
Jan 2026
2026
Latest Journal Issues
Nuclear Science and Engineering
August 2026
Nuclear Technology
July 2026
Fusion Science and Technology
Latest News
The deadline arrives: Checking in on the Reactor Pilot Program
On May 23, 2025, President Trump signed Executive Order 14301, “Reforming Nuclear Reactor Testing at the DOE,” which instructed the Department of Energy to create a Reactor Pilot Program (RPP)—a new system in which companies could pursue DOE authorization to build and test their first-of-a-kind nuclear technologies. EO 14301 set an ambitious goal for that program: three reactors achieving criticality by July 4, 2026.
Seungsu Yuk, Nam Zin Cho
Nuclear Science and Engineering | Volume 181 | Number 1 | September 2015 | Pages 1-16
Technical Paper | doi.org/10.13182/NSE14-88
Articles are hosted by Taylor and Francis Online.
In this paper, we present two novel approaches to reactor core analysis: (1) whole-core fine-group deterministic transport calculations are accelerated by a partial-current-based coarse-mesh finite-difference (p-CMFD) method, and (2) a whole-core domain is decomposed into nonoverlapping local problems, with local problem transport solutions then embedded within the p-CMFD methodology in a two-level iterative scheme to provide a whole-core transport solution. To solve three-dimensional (3-D) reactor problems, both approaches use the two-dimensional/one-dimensional (2-D/1-D) fusion method as a solution kernel, which employs a 2-D method of characteristics in the radial direction and a 1-D SN-like method in the axial direction. A refinement sensitivity study of a 3-D boiling water reactor assembly problem shows the stability and accuracy of the 2-D/1-D fusion method. We report the results of these two approaches as applied to three whole-core configurations of the C5G7 OECD/NEA 3-D benchmark problem and to a modified C5G7 benchmark problem with explicitly modeled cladding.