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Education, Training & Workforce Development
The Education, Training & Workforce Development Division provides communication among the academic, industrial, and governmental communities through the exchange of views and information on matters related to education, training and workforce development in nuclear and radiological science, engineering, and technology. Industry leaders, education and training professionals, and interested students work together through Society-sponsored meetings and publications, to enrich their professional development, to educate the general public, and to advance nuclear and radiological science and engineering.
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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.
C. Eric Triplett, Robert E. Canaan, Dale E. Klein
Nuclear Technology | Volume 130 | Number 1 | April 2000 | Pages 99-110
Technical Note | Thermal Hydraulics | doi.org/10.13182/NT00-A3080
Articles are hosted by Taylor and Francis Online.
Natural convection heat transfer was experimentally investigated in a staggered array of heated cylinders, oriented horizontally within a rectangular isothermal enclosure. The test conditions were characteristic of a spent-fuel assembly during transport or horizontal dry storage. The assembly was configured with a pitch-to-diameter ratio of 1.33 and backfilled with pressurized helium or nitrogen. The backfill pressure was varied between 1 and 5 atm, while the assembly power was varied between 1 and 5 W per heater rod. The resulting data are presented in the form of Nusselt-Rayleigh number correlations, where the Nusselt number has been corrected for thermal radiation using a numerical technique. The staggered-array data are compared to previous data for a similar-pitch aligned rod array (a simulated boiling water reactor fuel assembly) to determine if convective heat transfer is enhanced or hindered in a staggered configuration. For the overall array, both the staggered and aligned configurations yield Nusselt-Rayleigh curves with a three-regime trend, which suggests distinct conduction and convection regimes separated by a transition regime. For lower Rayleigh numbers (<106), representative of the conduction regime, the aligned-array Nusselt number is 10 to 12% higher than the corresponding staggered-array value. However, in the convection regime at higher Rayleigh numbers, the staggered-array Nusselt number slightly exceeds the aligned- array Nusselt number. This is attributed to the fact that the staggered array begins to transition into the convection regime at lower Rayleigh number than the aligned array. For both configurations, the slope of the Nusselt-Rayleigh curve in the convection regime suggests turbulent flow conditions.
