ANS is committed to advancing, fostering, and promoting the development and application of nuclear sciences and technologies to benefit society.
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Division Spotlight
Operations & Power
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.
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.
Pan Wu, David Novog
Nuclear Technology | Volume 205 | Number 1 | January-February 2019 | Pages 364-376
Technical Paper | doi.org/10.1080/00295450.2018.1495000
Articles are hosted by Taylor and Francis Online.
The CTF code is a subchannel thermal-hydraulic code developed based on the COBRA-TF code. In this work, the CTF code is used to predict the single- and two-phase heat transfer, pressure drop, onset of nucleate boiling, and dryout heat flux in water at several temperatures and pressures under steady-state and transient conditions. The conditions cover a range of pressures from 2 to 6 MPa, flows from 1000 to 2500 kg/(m2∙s), and inlet subcooling from 40°C to 70°C. Experimental heat balance tests show agreement between coolant enthalpy change and the electrical power with a difference of no more than 1.0%. Steady-state experiments were performed at constant inlet conditions in a cylindrical directly heated Inconel test section where the wall temperatures were measured at each power level. For each steady-state test, the experimental boiling curve is compared to CTF predictions. Transient experiments were performed by initiating a blowdown from the test section outlet plenum using a fast-acting valve with an open time of less than 100 ms. The time of dryout in these transient experiments is compared with the CTF results to clarify the pressure transient effect on the dryout prediction.