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Radiation Protection & Shielding
The Radiation Protection and Shielding Division is developing and promoting radiation protection and shielding aspects of nuclear science and technology — including interaction of nuclear radiation with materials and biological systems, instruments and techniques for the measurement of nuclear radiation fields, and radiation shield design and evaluation.
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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.
Albert G. Gu
Nuclear Technology | Volume 177 | Number 2 | February 2012 | Pages 157-175
Technical Paper | Fission Reactors | doi.org/10.13182/NT12-A13363
Articles are hosted by Taylor and Francis Online.
This paper introduces a combined micro and macro (CMM) parameter perturbation theory for boiling water reactor (BWR) lattice design and optimization, which involves a large number of independent design variables and a large scale of variations. With this theory, engineers are able to meet the challenges from both accuracy and speed requirements. This theory was applied to the BWR fuel assembly lattice design in AREVA. A BWR fast lattice simulator (FLS) and a BWR fuel assembly lattice optimizer (BALO) were built and assisted engineers working on the lattice design and optimization. In addition to the discussion of this theory, the BALO/FLS calculation results are used to show that this theory can meet both speed and accuracy criteria of design as well as cover the large design range. Moreover, the results also show that two major perturbation issues in BWR lattice design and optimization, i.e., the large swing of average lattice enrichment and the thermal neutron black absorber's distribution as burnable poison can be resolved with the CMM perturbation theory. Finally, it is pointed out that the macro parameter perturbation combined with the micro parameter perturbation is extremely important to the accuracy.
