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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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U.S. nuclear supply chain: Ready for liftoff
Craig Piercycpiercy@ans.org
This month, September 8–11, the American Nuclear Society is teaming up with the Nuclear Energy Institute to host our first-ever Nuclear Energy Conference and Expo—NECX for short—in Atlanta. This new meeting combines ANS’s Utility Working Conference and NEI’s Nuclear Energy Assembly to form what NEI CEO Maria Korsnick and I hope will be the premier nuclear industry gathering in America.
We did this because after more than four decades of relative stagnation, the U.S. nuclear supply chain is finally entering a new era of dynamic growth. This resurgence is being driven by several powerful and increasingly durable forces: the explosive demand for electricity from artificial intelligence and data centers, an unprecedented wave of public and private acceptance of—and investment in—advanced nuclear technologies, and a strong market signal for reliable, on-demand power. Add the recent Trump administration executive orders on nuclear into the mix, and you have all the makings of an accelerant-rich business environment primed for rapid expansion.
Yasunori Bessho, Yuichiro Yoshimoto, Osamu Yokomizo, Ryutaro Yamashita, Masumi Ishikawa, Akio Toba
Nuclear Technology | Volume 117 | Number 3 | March 1997 | Pages 281-292
Technical Paper | Nuclear Reactor Safety | doi.org/10.13182/NT97-A35342
Articles are hosted by Taylor and Francis Online.
Development and qualification results are described for a three-dimensional, time-domain core dynamics analysis program for commercial boiling water reactors (BWRs). The program allows analysis of the reactor core with a detailed mesh division, which eliminates cal-culational ambiguity in the nuclear-thermal-hydraulic stability analysis caused by reactor core regional division. During development, emphasis was placed on high calculational speed and large memory size as attained by the latest supercomputer technology. The program consists of six major modules, namely a core neutronics module, a fuel heat conduction/transfer module, a fuel channel thermal-hydraulic module, an upper plenum/separator module, a feedwater/recirculation flow module, and a control system module. Its core neutronics module is based on the modified one-group neutron kinetics equation with the prompt jump approximation and with six delayed neutron precursor groups. The module is used to analyze one fuel bun dle of the reactor core with one mesh (region). The fuel heat conduction/transfer module solves the onedimensional heat conduction equation in the radial direction with ten nodes in the fuel pin. The fuel channel thermal-hydraulic module is based on separated three-equation, two-phase flow equations with the drift flux correlation, and it analyzes one fuel bundle of the reactor core with one channel to evaluate flow redistribution between channels precisely. Thermal margin is evaluated by using the GEXL correlation, for example, in the module. In the upper plenum/separator module, the upper plenum is modeled as a single volume in the thermal-equilibrium state and water spiraling in the separator is modeled by an effective length in the momentum equation. In the feedwater/recirculation flow module, the single-phase flow model is solved with the assumption of incompressive flow. Finally, the control system module includes the recirculation flow control minimodule, the pressure control minimodule, and the feedwater control minimodule, as well as the interlock functions, which work during a transient to allow analysis of general transient phenomena. The program was verified to provide satisfactory results within reasonable computational time based on application analysis of stability and scram phenomena in a BWR-5 type plant.
