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The Radiation Protection and Shielding Division is developing and promoting radiation protection and shielding aspects of nuclear science and technology — including interaction of nuclear radiation with materials and biological systems, instruments and techniques for the measurement of nuclear radiation fields, and radiation shield design and evaluation.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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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.
Soon Sam Kim, Jerry L. Judd
Nuclear Technology | Volume 110 | Number 1 | April 1995 | Pages 71-85
Fission Reactor | Burnup Credit | doi.org/10.13182/NT95-A35097
Articles are hosted by Taylor and Francis Online.
Fission rate monitor measurements and startup testing data recorded during operation of the Advanced Test Reactor (ATR) have been used to validate a three-dimensional PDQ full-core model developed for the physics analysis to support an updated final safety analysis report. The three-dimensional analysis utilizes the flux synthesis technique as well as the explicit method in solving for the spatial flux distribution in the core. Measured data used for comparison are specific powers from a string offission rate monitors, located in water channels of individual fuel elements, as well as the lobe and fuel element powers. Good agreement was observed in the specific power comparison. For the overall pointwise data, the mean errors were within 1.6% with a standard deviation of ±9%. An excellent agreement was observed for the fuel element power except for a few fuel positions in the corner lobes. Measured ATR startup testing data are also compared with the PDQ calculated values. The PDQ calculated parameters were conservative with respect to measured data. The validation study provided valuable data for assessment of the three-dimensional analytical model and techniques to be employed in the ATR physics analysis. The study also indicated that the PDQ three-dimensional flux synthesis solution technique is an economical and reasonably accurate method for determining global and local three-dimensional power distributions in the core.
