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Isotopes & Radiation
Members are devoted to applying nuclear science and engineering technologies involving isotopes, radiation applications, and associated equipment in scientific research, development, and industrial processes. Their interests lie primarily in education, industrial uses, biology, medicine, and health physics. Division committees include Analytical Applications of Isotopes and Radiation, Biology and Medicine, Radiation Applications, Radiation Sources and Detection, and Thermal Power Sources.
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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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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.
R. D. Lawrence, J. J. Dorning
Nuclear Science and Engineering | Volume 76 | Number 2 | November 1980 | Pages 218-231
Technical Paper | doi.org/10.13182/NSE80-A19452
Articles are hosted by Taylor and Francis Online.
A nodal method for the solution of the multidimensional neutron diffusion equation is developed and evaluated. The method is based on the linear form of the nodal balance equation written in terms of the average partial currents across the surfaces of the node. Green's functions for one-dimensional in-group diffusion-removal operators are used to generate a coupled set of one-dimensional integral equations defined over a subdomain or node. These integral equations represent an exact (local) solution to the coupled set of one-dimensional differential equations obtained by spatially integrating the multidimensional diffusion equation over directions transverse to each coordinate direction. The integral equations are approximated using a weighted residual procedure applied within each node. The resulting matrix equations, when solved in conjunction with the linear form of the nodal balance equation, provide the necessary additional relationships between the interface partial currents and the flux within the node. The nodal method is applied to several two- and three-dimensional light water reactor benchmark problems and to a four-group liquid-metal fast breeder reactor problem. These results demonstrate the capability of the method to yield very accurate steady-state and transient results in significantly smaller computing times than those required by standard finite difference methods.