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Division Spotlight
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.
Meeting Spotlight
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.
Azin Behdadi, John C. Luxat
Nuclear Technology | Volume 181 | Number 1 | January 2013 | Pages 157-169
Technical Paper | Special Issue on the 14th International Topical Meeting on Nuclear Reactor Thermal Hydraulics (NURETH-14) / Fission Reactors; Reactor Safety; Thermal Hydraulics | doi.org/10.13182/NT13-A15764
Articles are hosted by Taylor and Francis Online.
Heavy water moderator surrounding each fuel channel is one of the important safety features in CANDU reactors since it provides an in situ passive heat sink for the fuel in situations where other engineered means of heat removal from fuel channels have failed. In a critical-break loss-of-coolant-accident scenario, fuel cooling becomes severely degraded because of rapid flow reduction in the affected flow pass of the heat transport system. This can result in pressure tubes (PTs) experiencing significant heatup during early stages of the accident when coolant pressure is still high, thereby causing uniform thermal creep strain (ballooning) of the PT in contact with its calandria tube (CT). The contact of the hot PT with the CT causes rapid redistribution of stored heat from the PT to the CT and a large heat flux spike from the CT to the moderator fluid. For conditions where subcooling of the moderator fluid is low, this heat flux spike can cause dryout of the CT. This can detrimentally affect channel integrity if the CT postdryout temperature becomes sufficiently high to result in continued thermal creep strain deformation of both the PT and the CT. The focus of this work is to develop a mechanistic model to predict critical heat flux (CHF) on the CT surface following a contact with its PT. A COMSOL multiphysics model using a two-dimensional transient fluid-thermal analysis of the CT surface undergoing heatup is used to predict the flow and temperature profiles on the CT surface. A mechanistic CHF model is to be proposed based on a concept of wall dry patch formation, prevention of rewetting, and subsequent dry patch spreading.