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Growth beyond megawatts
Hash Hashemianpresident@ans.org
When talking about growth in the nuclear sector, there can be a somewhat myopic focus on increasing capacity from year to year. Certainly, we all feel a degree of excitement when new projects are announced, and such announcements are undoubtedly a reflection of growth in the field, but it’s important to keep in mind that growth in nuclear has many metrics and takes many forms.
Nuclear growth—beyond megawatts—also takes the form of increasing international engagement. That engagement looks like newcomer countries building their nuclear sectors for the first time. It also looks like countries with established nuclear sectors deepening their connections and collaborations. This is one of the reasons I have been focused throughout my presidency on bringing more international members and organizations into the fold of the American Nuclear Society.
Anil K. Prinja, Patrick F. O’Rourke, Scott D. Ramsey
Nuclear Science and Engineering | Volume 199 | Number 1 | April 2025 | Pages S249-S263
Research Article | doi.org/10.1080/00295639.2024.2340167
Articles are hosted by Taylor and Francis Online.
Neutron chain survival and ultimate divergence in coupled multiplying assemblies, linked by intercepted leaking neutrons, are considered. Nonlinear equations are formulated for the dynamic probability of survival and static probability of initiation (POI) with assembly intercept fractions computed using a view factor model. Numerical solutions are obtained for up to four coupled assemblies, revealing a sensitive dependence on interassembly coupling strength. The results indicate that a chain will not diverge with certainty in a subcritical or critical system but that divergence will occur with some probability POI > 0 that increases with coupling strength. Additionally, at keff = 1, the stable subcritical solution branch is observed to bifurcate into two branches, one of which is shown through linear stability analysis to be unstable.