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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.
David P. Weber
Nuclear Technology | Volume 45 | Number 3 | October 1979 | Pages 203-218
Technical Paper | Reactor | doi.org/10.13182/NT79-A32291
Articles are hosted by Taylor and Francis Online.
The assessment of the consequences of hypothetical accidents in liquid-metal-cooled fast reactors often requires interaction between analysis and in-pile experiments, where experiments must provide geometry, boundary conditions, and thermal profiles that are prototypical of the accident scenario. Neutronic heating of test samples initially produces atypical thermal profiles, and a time period is required to elapse for thermal inversion. An analytic transient heat conduction analysis using multiregion eigenfunctions is provided to determine the space-time temperature profiles. With an assumed weak temporal dependence for eigenfunctions greater than the first, a determination of the motion of the position of maximum temperature is made, leading to a simple expression for the time to thermally invert completely, which requires knowledge of only the first eigenvalue and the expansion coefficient of the source for the fundamental mode, with similar analysis providing an estimate of the time to reach melting. A functional relationship is established between the operating reactor power, the thermal properties of the materials, and the boundary conditions to ensure satisfaction of both criteria of rapid thermal inversion and maximum temperatures above prescribed levels, such as melting. The analysis is then applied to a proposed in-pile experiment for studying pool boilup in internally heated fuel-steel pools with nuclear heated walls. It is shown that for a variety of external boundary conditions, a reactor power level may be chosen to ensure integrity of the insulating wall while simulating the pool boilup phenomena without the necessity of enrichment grading to enhance thermal inversion.