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Nuclear Nonproliferation Policy
The mission of the Nuclear Nonproliferation Policy Division (NNPD) is to promote the peaceful use of nuclear technology while simultaneously preventing the diversion and misuse of nuclear material and technology through appropriate safeguards and security, and promotion of nuclear nonproliferation policies. To achieve this mission, the objectives of the NNPD are to: Promote policy that discourages the proliferation of nuclear technology and material to inappropriate entities. Provide information to ANS members, the technical community at large, opinion leaders, and decision makers to improve their understanding of nuclear nonproliferation issues. Become a recognized technical resource on nuclear nonproliferation, safeguards, and security issues. Serve as the integration and coordination body for nuclear nonproliferation activities for the ANS. Work cooperatively with other ANS divisions to achieve these objective nonproliferation policies.
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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.
Koroush Shirvan, Mujid Kazimi
Nuclear Technology | Volume 184 | Number 3 | December 2013 | Pages 287-296
Technical Paper | Fission Reactors | doi.org/10.13182/NT13-A24986
Articles are hosted by Taylor and Francis Online.
A boiling water reactor (BWR) with high power density (BWR-HD) was designed through an optimization search that was constrained to a square lattice fuel array. It has a power level of 5000 MW(thermal), equivalent to a 26% uprated Advanced BWR (ABWR), the latest version of operating BWR. This results in economic benefits, estimated to be [approximately]20% capital and operations and maintenance costs and similar total fuel cycle cost per unit electricity. The stability of the ABWR and BWR-HD were assessed for the three modes of density wave oscillations: single-channel thermal hydraulics, coupled neutronic regional core oscillations, and coupled neutronic global core oscillations. The sensitivity to design parameters such as inlet subcooling, presence of water rods, and inlet orifice coefficient as well as to changes in reactor power, flow rate, and void coefficient were examined using the STAB frequency domain code. The BWR-HD's stability performance and sensitivity were concluded to be similar to those of the ABWR. The results of the frequency domain analysis indicate that the shorter core and smaller void coefficient lowered the oscillation decay ratio, while the cooler inlet temperature and higher void fraction increased the decay ratio. Also the S3K code was utilized to perform three-dimensional coupled stability analysis and to formulate an operation exclusion zone region for the BWR-HD design. It was found that a reduction in the allowable operational zone of the BWR-HD design is warranted, due to its decay ratio being higher than that of the ABWR for whole-core oscillations. However, the inlet orificing (pressure loss coefficient) of the assemblies can be increased to obtain the same stability performance as the ABWR. This strategy is deemed plausible since the pumping power needed for the BWR-HD, even with the increase in pressure losses at the inlet of assemblies, will still be less than that of the ABWR and will have negligible effects on the safety performance.