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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
ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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
Norway’s Halden reactor takes first step toward decommissioning
The government of Norway has granted the transfer of the Halden research reactor from the Institute for Energy Technology (IFE) to the state agency Norwegian Nuclear Decommissioning (NND). The 25-MWt Halden boiling water reactor operated from 1958 to 2018 and was used in the research of nuclear fuel, reactor internals, plant procedures and monitoring, and human factors.
Jin-Seok Hwang, Jong-Won Kim, Heon-Uk Nam, Goon-Cherl Park
Nuclear Technology | Volume 176 | Number 2 | November 2011 | Pages 260-273
Technical Paper | Thermal Hydraulics | doi.org/10.13182/NT11-A13300
Articles are hosted by Taylor and Francis Online.
A major safety factor in marine reactor design, critical heat flux (CHF), is assessed using the MARS system analysis code under heaving conditions. As gravity acceleration changes, the CHF is affected by the thermal hydraulics in the reactor through inlet flow fluctuations. Performing the analysis with the MARS code, which uses the properties of water for the working fluid, requires applying the CHF experimental data using fluid-to-fluid (FTF) scaling because most CHF experiments are conducted with Freon (R-113) as the working fluid. The FTF scaling methods suggested by Ahmad, Katto, and Coffield are adopted and compared. Otsuji et al.'s experiment, which was conducted using mass flow rate oscillation, is applied to evaluate the capability of MARS for heaving conditions. According to the calculations the FTF methods of Ahmad, Katto, and Coffield show good agreement (within an error of ±10.73% for Otsuji et al.'s experiment) for inlet flow rate oscillation corresponding to gravity acceleration in a vertical direction. In addition, variation of the acceleration affects the flow conditions, such as the mass flow rate and the void fraction. Thus, MARS has a noteworthy ability to predict the CHF for heaving conditions by simulating inlet flow rate oscillation.