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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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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.
J. T. Marti, J. P. Schneeberger
Nuclear Science and Engineering | Volume 13 | Number 1 | May 1962 | Pages 1-5
Technical Paper | doi.org/10.13182/NSE62-A26120
Articles are hosted by Taylor and Francis Online.
A critical system consisting of a regular infinite array of cylindrical channels of any cross section in a homogeneous multiplying medium is divided into equivalent cells of finite height. For such a cell two-group diffusion theory is applied with additional terms for the loss and gain of neutrons by the channels. The resulting integral-differential equations are solved with sufficient accuracy by the perturbation method, giving the reactivity loss due to the channels. With the method proposed the neutron leakage at the ends of the channels is included and deviations from the original unperturbed flux of the reactor without channels are taken into account. The results are compared with calculations based on the usual assumption of unperturbed flux, using the Behrens formula to compute the diffusion lengths. It is shown that reactivity calculations are also possible for arrays of finite extent, assuming separability of the flux in an axial and a radial part.