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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
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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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Latest News
Take steps on SNF and HLW disposal
Matt Bowen
With a new administration and Congress, it is time once again to ponder what will happen—if anything—on U.S. spent nuclear fuel and high-level waste management policy over the next few years. One element of the forthcoming discussion seems clear: The executive and legislative branches are eager to talk about recycling commercial SNF. Whatever the merits of doing so, it does not obviate the need for one or more facilities for disposal of remaining long-lived radionuclides. For that reason, making progress on U.S. disposal capabilities remains urgent, lest the associated radionuclide inventories simply be left for future generations to deal with.
In March, Rick Perry, who was secretary of energy during President Trump’s first administration, observed that during his tenure at the Department of Energy it became clear to him that any plan to move SNF “required some practical consent of the receiving state and local community.”1
Seungmin Oh, Haijing Gao, Shripad T. Revankar
Nuclear Technology | Volume 158 | Number 2 | May 2007 | Pages 208-218
Technical Paper | Nuclear Reactor Thermal Hydraulics | doi.org/10.13182/NT07-A3836
Articles are hosted by Taylor and Francis Online.
An experimental study and best-estimate thermal-hydraulic code model assessment is performed to investigate the characteristics of the filmwise condensation with and without noncondensable gas in a passive condenser system. A vertical condenser tube is submerged in a water pool, where the heat from the condenser tube is removed through boiling heat transfer. Data are obtained for various inlet steam flow rates and noncondensable gas mass fractions at various system pressure conditions for two tube inner diameters: 26.6 and 52.5 mm. Experimental data are compared with analysis for complete condensation and flow-through conditions. Degradation of the condensation with noncondensable gas is investigated, where the condensation heat transfer coefficient decreases with the noncondensable gas. Experimental results are simulated with the RELAP5 code using two different condensation models. Code predictions are compared with experimental data, and the results indicate that there is a need for improved condensation models in RELAP5.