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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.
Shashi Kant Verma, S. L. Sinha, D. K. Chandraker
Nuclear Science and Engineering | Volume 190 | Number 2 | May 2018 | Pages 195-208
Technical Paper | doi.org/10.1080/00295639.2017.1413874
Articles are hosted by Taylor and Francis Online.
The objective of the present work is to establish the effect of spacer and geometrical parameters of nuclear fuel rods on the turbulent mixing rate in subchannels of the advanced heavy water reactor (AHWR) rod bundle. Experiments on the AHWR rod bundle have been carried out in a scaled test facility developed at Bhabha Atomic Research Centre, Trombay, Maharashtra. In order to confirm the validity of the proposed method, experimental data on the turbulent mixing rate were obtained using a tracer technique under adiabatic conditions with 3.5-m vertical test channels, consisting of three subchannels. The spacer was installed at 2963 mm (37 mm at the end of the mixing section), 2926 mm (74 mm at the end of the mixing section), and 2889 mm (111 mm at the end of the mixing section) from the entry section in the test section, respectively, for three different positions. The experimental results (blockage ratio 4%) have been compared with the case without spacer and finally new correlations have been developed between average mixing number, combined Reynolds number, and gap-to-centroidal ratio (S/δ). The range of average Reynolds number covered was 0 to 6424. The correlation is applicable for a vertical pressure tube–type boiling water reactor (AHWR) with a reasonable accuracy. The instrument was calibrated prior to each set of analyses with standard solution. It predicts a reasonable mixing at a higher S/δ as compared to without spacer, which is the most improved feature of the correlation when compared with the existing ones. The uncertainty analysis has been carried out for the measurement of flow rate, concentration, and height of the test section. The proposed correlation may be applicable for the thermal-hydraulic design of an AHWR with an improved accuracy. A complete set of mixing data was obtained which can be used to calibrate thermal-hydraulic codes.