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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.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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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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X-energy, Dow apply to build an advanced reactor project in Texas
Dow and X-energy announced today that they have submitted a construction permit application to the Nuclear Regulatory Commission for a proposed advanced nuclear project in Seadrift, Texas. The project could begin construction later this decade, but only if Dow confirms “the ability to deliver the project while achieving its financial return targets.”
Robert P. Martin, Simone H. Morgan, Christopher Cragg
Nuclear Technology | Volume 193 | Number 1 | January 2016 | Pages 200-212
Technical Paper | Special Issue on the RELAP5-3D Computer Code | doi.org/10.13182/NT14-140
Articles are hosted by Taylor and Francis Online.
Evaluation methodologies are under development at BWX Technologies (BWXT) to support licensure of the BWXT small modular reactor. In these evaluation methodologies, RELAP5-3D is being used as the computation engine for reactor coolant system performance. To facilitate analyses, the RelapManager code was developed as a Windows-based graphical user interface for RELAP5-3D. It is used to edit RELAP5-3D input models and develop simulation suites with unique attention to the preparation of Quality Program records required per 10 CFR 50 Appendix B. The software has been created with Visual Studio employing the .NET integrated development environment. The programming focal point for RelapManager is an XML schema that captures the modeling rules inherent in RELAP5-3D. It transforms an existing input model into XML, which, through a large library of functions created to support XML file types, provides a rich user experience capable of improving productivity and quality.
RelapManager includes specialized features for the preparation of uncertainty and sensitivity/importance analyses, execution on a remote server, plotting, and data checking against the modeling rules. As a demonstration of these features, an uncertainty and importance analysis has been prepared using the “Typical PWR” test problem provided with the nominal RELAP5-3D release package. RelapManager takes as input uncertainty models characterizing the expected domain of model parameter variability. Subsequently, a calculation suite derived from sampling the uncertainty domain is described, and a run script is prepared by RelapManager. Figure of merit results are gathered by RelapManager and analyzed using a variance-based sensitivity analysis method.
