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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
Standards Program
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.
Junda Zhang, Tao Li, Zhirui Shen, Xiangyue Li, Jinbiao Xiong, Xiang Chai, Xiaojing Liu, Tengfei Zhang
Nuclear Science and Engineering | Volume 198 | Number 5 | May 2024 | Pages 1097-1121
Research Article | doi.org/10.1080/00295639.2023.2227838
Articles are hosted by Taylor and Francis Online.
This work describes the research of high-fidelity multiphysics models for the MegaPower nuclear reactor, a megawatt-level heat pipe reactor. Combining the Monte Carlo neutronics model, the heat pipe analysis model, the fuel analysis model, and the thermoelasticity model produces the Multi-Physics Coupling code for Heat pipe nuclear reactors (MPCH) code platform. Using the heat pipe analysis model, a database of heat pipes is generated to save computing costs. Comparison is made among four calculating modes with differing degrees of coupling. It was discovered that the thermal expansion effect reduces core reactivity by 537 ± 11 pcm and the temperature feedback coefficient by 61%. With the incorporation of the heat pipe module, a temperature difference arises between the wall of heat pipes, which can reach a maximum value of 80 K at steady state. Simultaneously, the global fuel rod temperature difference increases from 34 K (under the assumption of uniform heat pipe wall temperature) to 93 K, and the monolith temperature variance increases from 34 to 108 K. At the periphery of the monolith, the increased temperature variation causes a monolithic stress of 188.6 MPa. To further investigate the safety of the reactor, three-heat-pipe-failure scenarios are evaluated. The heat pipe analysis model reveals that a single heat pipe failure results in a monolith peak temperature of 1046 K, giving a maximum monolith stress of 237 MPa. The maximum monolith stresses and temperatures for the two-heat-pipe-failure scenario and the three-heat pipe-failure scenario are 330 MPa/1128 K and 471 MPa/1233 K, respectively. In steady-state operation, the stresses exceed the yield tensile strength (131MPa) whereas those generated by the failure of three heat pipes exceed the ultimate tensile strength (345 MPa) in high temperature. These results illustrate the necessity of including coupled multiphysics models into the design and safety evaluation of innovative nuclear reactors.