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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.
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2025 ANS Annual Conference
June 15–18, 2025
Chicago, IL|Chicago Marriott Downtown
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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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DOE’s Wright appears before House subcommittee
Wright
Secretary of Energy Chris Wright testified before a hearing of the U.S. House of Representatives Committee on Appropriations, Subcommittee on Energy and Water Development and Related Agencies, on May 7, to answer questions about the DOE budget and priories for fiscal year 2026.
Wright’s testimony: Wright said that the DOE was taking steps to accelerate innovation in commercial nuclear development. “In the past 100 days, DOE has issued two disbursements to support the reopening of Michigan’s Palisades nuclear energy plant. We allocated high-assay low-enriched uranium material to five U.S. advanced nuclear reactor developers to boost domestic reactor deployment.”
He added that it was imperative for the nation to strengthen its nuclear future and that he would take immediate action to accelerate the deployment of small modular reactors.
A. Rashkovan, D. McClure, D. R. Novog
Nuclear Science and Engineering | Volume 177 | Number 2 | June 2014 | Pages 141-155
Technical Paper | doi.org/10.13182/NSE13-4
Articles are hosted by Taylor and Francis Online.
Grid spacers within nuclear fuel assemblies play a critical role in fuel performance and contribute to safety margins by enhancing the margin to the critical heat flux. The Organisation for Economic Co-operation and Development/Nuclear Energy Agency has organized a computational benchmark wherein the prediction of flows and turbulence downstream of a mixing-type grid spacer are examined. Studies performed by McMaster University using STAR-CCM+ for the final submission to this MATiS-H blind benchmark exercise related to inter-subchannel mixing and turbulence are presented in this paper. The rationale behind the choice of the computational scheme along with comparisons of the submitted results to the experiments is reported. The goal at the outset of the study was to obtain a reasonably accurate solution with a minimum number of nodes and appropriate turbulence models such that the results would be relevant for engineering applications that include property variations and heat transfer. As such, advanced modeling methods such as large eddy simulation and unsteady Reynolds-averaged Navier-Stokes (URANS) were not included within the scope of the models tested. However, URANS was used to study some specific separate-effect flow features within the grid spacer, and these tests were compared to their steady counterparts.
A comprehensive separate-effect study was performed first in order to finalize the computational scheme for the submission. Several partial geometries were studied for steady and unsteady behavior as well as for mesh sensitivity, turbulence, and wall modeling effects. A series of successively more complex simulations, sometimes involving unsteady modeling, was performed up to and including a study of similar 5 × 5 rod bundle geometry reported in the literature. The final submission results are presented in the paper and are compared with the benchmark data that have recently been released.