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Conference Spotlight
2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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Shifting the paradigm of supply chain
Chad Wolf
When I began my nuclear career, I was coached up in the nuclear energy culture of the day to “run silent, run deep,” a mindset rooted in the U.S. Navy’s submarine philosophy. That was the norm—until Fukushima.
The nuclear renaissance that many had envisioned hit a wall. The focus shifted from expansion to survival. Many utility communications efforts pivoted from silence to broadcast, showcasing nuclear energy’s elegance and reliability. Nevertheless, despite being clean baseload 24/7 power that delivered a 90 percent capacity factor or higher, nuclear energy was painted as risky and expensive (alongside energy policies and incentives that favored renewables).
Economics became a driving force threatening to shutter nuclear power. The Delivering the Nuclear Promise initiative launched in 2015 challenged the industry to sustain high performance yet cut costs by up to 30 percent.
C. K. Sanathanan, J. C. Carter, F. Miraldi
Nuclear Science and Engineering | Volume 23 | Number 2 | October 1965 | Pages 130-137
Technical Paper | doi.org/10.13182/NSE65-A28137
Articles are hosted by Taylor and Francis Online.
In Part I of this series, the authors have developed mathematical techniques to investigate the dynamics of coolant circulation in boiling-water nuclear reactors. This paper is an attempt to apply those techniques to various specific situations. A natural-circulation loop with a single heated channel is considered first. Dependence of the degree of stability upon the steady-state profile of the channel heat flux and the channel length are investigated. The influence of the pressure drops in the downcomer and at the channel inlet upon the transient two-phase flow is studied. The steady-state perturbations in the void fraction and velocity due to a small perturbation in the channel heat flux are predicted. The findings of the present study compare favorably with those obtained by the simplifying assumption made by the earlier investigators that the slip ratio is a constant along the channel length. The more interesting system with two or more channels operating in parallel with a common downcomer is considered next. The strength of the coupling between the dynamics of the flows through the channels increases with the pressure drop in the common downcomer, and this phenomenon is considered quantitatively. Results obtained theoretically are substantiated by comparison with those obtained through elaborate numerical methods and previous observations.