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Aerospace Nuclear Science & Technology
Organized to promote the advancement of knowledge in the use of nuclear science and technologies in the aerospace application. Specialized nuclear-based technologies and applications are needed to advance the state-of-the-art in aerospace design, engineering and operations to explore planetary bodies in our solar system and beyond, plus enhance the safety of air travel, especially high speed air travel. Areas of interest will include but are not limited to the creation of nuclear-based power and propulsion systems, multifunctional materials to protect humans and electronic components from atmospheric, space, and nuclear power system radiation, human factor strategies for the safety and reliable operation of nuclear power and propulsion plants by non-specialized personnel and more.
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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.
Staffan Qvist, Ehud Greenspan
Nuclear Science and Engineering | Volume 182 | Number 2 | February 2016 | Pages 197-212
Technical Paper | doi.org/10.13182/NSE14-135
Articles are hosted by Taylor and Francis Online.
For a reactor to establish a sustainable breed-and-burn (B&B) mode of operation, its fuel has to reach a minimum level of average burnup. The value of the minimum required average discharge burnup strongly depends on the core design details. Using the extended neutron balance method, it is possible to quantify the impact of major core design choices on the minimum required burnup in a B&B core. Relevant design variables include the fuel chemical form, nonactinide mass fraction of metallic fuel, feed-fuel fissile fraction, fuel rod pitch-to-diameter ratio (P/D), average neutron flux level, and fraction of neutron loss. Metallic fuels have been found to be the only viable fuel options for a realistic near-term B&B reactor. For the core designs we have studied, it was not possible to sustain B&B operation using oxide fuel that is not enriched, while nitride and carbide fuels may only work in highly ideal low-leakage systems at very high levels of discharge burnup and, hence, neutron irradiation damage. The minimum required burnup increases strongly with the total fraction of neutrons that is lost to leakage and reactivity control. The flux level has no effect on the neutron balance within the applicable range, and the average discharge burnup is also relatively insensitive to the fraction of fissile material in the feed fuel in the range from depleted uranium (0.2% 235U) to natural uranium (0.71% 235U). The minimum required burnup is most sensitive, in order of importance, to the fractional loss of neutrons, the Zr content in metallic fuel, and the fuel rod P/D. Changing the weight fraction of zirconium in metallic fuel by 1% (for example, from 10% to 9%) gives the same change in required discharge burnup as adjusting the P/D by 0.02 (for example, from 1.10 to 1.12).