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The Radiation Protection and Shielding Division is developing and promoting radiation protection and shielding aspects of nuclear science and technology — including interaction of nuclear radiation with materials and biological systems, instruments and techniques for the measurement of nuclear radiation fields, and radiation shield design and evaluation.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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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.
George Tsotridis
Fusion Science and Technology | Volume 32 | Number 1 | August 1997 | Pages 35-44
Technical Paper | First-Wall Technology | doi.org/10.13182/FST97-A19878
Articles are hosted by Taylor and Francis Online.
Plasma-facing components in tokamak-type fusion reactors are subjected to intense heat loads during plasma disruptions, which causes melting and evaporation of the surface layer. The influence of the beam cross section of the incident energy on the depths of heat-affected zones on pure tungsten metal has been studied by using a two-dimensional transient computer model that solves the equations of motion and energy. Results are presented for relatively long disruption times for different beam cross sections and for a range of energy densities. It is demonstrated that there exists a critical value of cross-section area beyond which any further increase has no appreciable influence on the resulting depths of molten layers. It is also demonstrated that as the cross section increases, the convective flows caused by surface tension gradients resulting from variations of surface impurities are confined at regions close to the periphery of the molten zone, whereas at the center of the molten pool, heat is transported in the molten metal by conduction. It is demonstrated that by increasing the beam cross-section area, the resulting depths of molten layers increase. However, there exists a critical value of cross section beyond which the resulting molten layer depths are invariant to the beam cross section. It is further appreciated that there are other important phenomena taking part during plasma disruptions, such as electromagnetic forces, but at this stage, such influences on the molten layers will not be studied. Nevertheless, the influence of the beam cross-sectional area would be of similar importance.