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Division Spotlight
Reactor Physics
The division's objectives are to promote the advancement of knowledge and understanding of the fundamental physical phenomena characterizing nuclear reactors and other nuclear systems. The division encourages research and disseminates information through meetings and publications. Areas of technical interest include nuclear data, particle interactions and transport, reactor and nuclear systems analysis, methods, design, validation and operating experience and standards. The Wigner Award heads the awards program.
Meeting Spotlight
2024 ANS Annual Conference
June 16–19, 2024
Las Vegas, NV|Mandalay Bay Resort and Casino
Standards Program
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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Can hydrogen be the transportation fuel in an otherwise nuclear economy?
Let’s face it: The global economy should be powered primarily by nuclear power. And it probably will by the end of this century, with a still-significant assist from renewables and hydro. Once nuclear systems are dominant, the costs come down to where gas is now; and when carbon emissions are reduced to a small portion of their present state, it will become obvious that most other sources are only good in niche settings. I mean, why use small modular reactors to load-follow when they can just produce that power instead of buffering it?
Yann Le Moigne (Westinghouse Electric Sweden AB), Paul Smeekes (Teollisuuden Voima Oyj), Matthew Solmos (Westinghouse)
Proceedings | 2018 International Congress on Advances in Nuclear Power Plants (ICAPP 2018) | Charlotte, NC, April 8-11, 2018 | Pages 1115-1124
In a BWR, the cooler feedwater is injected in the downcomer of the reactor vessel where it mixes with the recirculation water that is separated from the generated steam at the exit of the core. In order to avoid high temperature fluctuations on the reactor vessel and the structures present in the downcomer, this mixing shall be performed in a controlled manner. In order to improve the design of the feedwater spargers in Olkiluoto Unit 1 and 2 in Finland, the thermal mixing of the feedwater with the reactor water in the vicinity of the spargers has been studied with transient Computational Fluid Dynamics (CFD) calculations. The studies have been performed at three different power levels. Unsteady Reynolds-Averaged Navier-Stokes (URANS) calculations have been performed to simulate about 40 s of the water mixing. The time history of the variations of the water temperature on the structures in the downcomer has been analyzed. The calculations have been run for several designs of the replacement spargers. The designs have been assessed using transient statistics of the temperature fluctuations. Minimizing the maximum amplitude of the temperature variations, the so-called peak-to-peak value, has been a design objective.