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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.
Siyang Huang, Qiqi Yan, Wenxi Tian, G. H. Su, Suizheng Qiu (Xi’an Jiaotong Univ)
Proceedings | Advances in Thermal Hydraulics 2018 | Orlando, FL, November 11-15, 2018 | Pages 44-56
In the nuclear power system, the critical heat flux (CHF) plays a crucial role in the reactor safety analysis. When CHF occurs, it will cause a sudden increase in the surface temperature, which would lead to the failure of fuel claddings and damage of the core. Considering the cross flow between neighboring channels, spacer grids and mixing vanes in the fuel assembly, the local flow conditions and the geometry of the flow channels make the prediction of CHF more complicated. In this paper, the departure from nucleate boiling (DNB) type CHF in rod bundle is investigated based on the coupled analysis of the subchannel method and a CHF mechanism model, i.e. the liquid sublayer dryout model. The liquid sublayer dryout model assumes that there is a thin liquid sublayer underneath a vapor blanket formed by the coalescence of small bubbles near the heated wall. The dryout of this sublayer will be regarded as the CHF occurrence. In present research, the homogeneous flow model is adopted in the subchannel analysis code to predict the local flow conditions for the rod bundle flow subchannels, which will be used as the input parameters for the liquid sublayer dryout model. In order to verify the method above, the predicted results are compared with the CHF Look-Up Table 2006 (LUT-2006) and the predicted results are in good agreement with the data in LUT-2006. In addition, the effects of rod bundle inlet subcooling, mass flux, heated length and motion conditions on CHF are analyzed.
