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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.
Sung Joong Kim, Lin-Wen Hu, Floyd Dunn
Nuclear Technology | Volume 182 | Number 3 | June 2013 | Pages 315-334
Technical Paper | Thermal Hydraulics | doi.org/10.13182/NT12-81
Articles are hosted by Taylor and Francis Online.
The Massachusetts Institute of Technology Research Reactor (MITR) is evaluating a transitional core conversion strategy for converting from high-enrichment uranium (HEU) to low-enrichment uranium (LEU) fuel. The objective of this study is to analyze steady-state operational safety margins and loss of primary flow (LOF) accidents for the postulated HEU-LEU transitional core configurations. The thermal-hydraulic calculation was performed using the RELAP5 MOD 3.3 code based on 7.40-MW reactor power, which is the limiting safety system settings of the current licensed reactor power of 6 MW. A lumped average and a single hot channel were modeled in each core configuration with radial peaking factors of 2.0 and 1.76 for HEU and LEU fuel elements, respectively. Four natural convection valves and two antisiphon valves were modeled for natural convective heat removal during the LOF transient. Two different hot-channel configurations and full- and side-channel geometries were evaluated because the unique design of the MITR fuel element can form these two types of geometries. RELAP5 calculation results suggest that the transitional core conversion strategy is feasible and that sufficient thermal-hydraulic safety margins can be maintained.
