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Accelerator Applications
The division was organized to promote the advancement of knowledge of the use of particle accelerator technologies for nuclear and other applications. It focuses on production of neutrons and other particles, utilization of these particles for scientific or industrial purposes, such as the production or destruction of radionuclides significant to energy, medicine, defense or other endeavors, as well as imaging and diagnostics.
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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.
Shlomo Ron, Judah Tzoref, Doron Gal
Nuclear Technology | Volume 97 | Number 3 | March 1992 | Pages 294-302
Technical Paper | Nuclear Reactor Safety | doi.org/10.13182/NT92-A34637
Articles are hosted by Taylor and Francis Online.
The amount of fission product release during a core heatup accident in a medium-sized high-temperature gas reactor depends on the size of the inadvertent opening in the primary circuit; this dependence is assessed. The opening triggers a depressurization event that is assumed to be coupled with the failure of the forced circulation in both decay-heat removal systems. The scenario investigated is a beyond-design-base accident. The DSNP modular simulation code is used. A two-dimensional model is developed to simulate the HTR-500 design. The study shows that the depressurization process does not contribute significantly to the sweeping out (from the primary circuit) of fission products released from the fuel during the core heatup. There is also no significant variation in the results when the opening size is >33 cm2, and only a slight sensitivity is found when the rupture size is between 3.3 and 33 cm2. The fission product release decreases considerably in the range from 1 to 3.3 cm2. The smallsized rupture is of major significance, as the failure of the relief valves to reclose increases the frequency of the event. In addition, the highest core temperature in the most severe depressurization accident scenario is evaluated, and its calculated value is lower than the graphite sublimation temperature. Although the simulation closely follows the German HTR-500 design, the conclusions may be applied to the general concept of the medium-sized high-temperature gas reactor.
