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Members focus on the dissemination of knowledge and information in the area of power reactors with particular application to the production of electric power and process heat. The division sponsors meetings on the coverage of applied nuclear science and engineering as related to power plants, non-power reactors, and other nuclear facilities. It encourages and assists with the dissemination of knowledge pertinent to the safe and efficient operation of nuclear facilities through professional staff development, information exchange, and supporting the generation of viable solutions to current issues.
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ANS Student Conference 2025
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Fusion Science and Technology
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.
M. Z. Hasan, T. Kunugi
Fusion Science and Technology | Volume 19 | Number 3 | May 1991 | Pages 1030-1035
Blanket Technology | doi.org/10.13182/FST91-A29478
Articles are hosted by Taylor and Francis Online.
Convective heat transfer in the thermally developing region in a coolant channel of the first wall and limiter/divertor plates of a fusion reactor has been analyzed numerically. The surface heat flux on a coolant channel in these plasma facing components varies circumferentially. The flow is assumed MHD fully developed laminar in a circular tube with insulating wall and in the presence of a transverse magnetic field. Both the circumferential variation of the surface heat flux and the presence of a transverse magnetic field greatly affect the steady-state Nusselt number and thermal entry length. At the point where the magnetic field is normal to the tube wall, the steady-state Nusselt number can be increased as much as by a factor of 2 compared with 4.36 for non-MHD flow (parabolic velocity profile) and uniform surface heat flux. The nonuniformity of surface heat flux, on the other hand, can reduce the Nusselt number at the same location (also the point of maximum heat flux) to about 3.0. The transverse magnetic field can increase the thermal entry length by about 40% compared with that for non-MHD flow and uniform heat flux. The nonuniformity of surface heat flux and transverse magnetic field combined can increase the thermal entry length by a factor of 4.6. Neglect of this decrease in Nusselt number can result in an underestimation of the film temperature drop by 38% to 64%. The increase in the entry length would not affect the thermal-hydraulic designs of the first wall and divertor plate because, even with this increase, the entry length is short for liquid-metal coolants.
