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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.
Mihály Makai
Nuclear Science and Engineering | Volume 86 | Number 3 | March 1984 | Pages 319-326
Technical Note | doi.org/10.13182/NSE84-A17561
Articles are hosted by Taylor and Francis Online.
In order to shorten the time of reactor core calculations, the actual core structure is often replaced by a simpler structure, such as a periodic lattice whose neutron flux is determined through some periodic microfluxes and through an overall macroflux. In the framework of the well-known perturbation formalism, it is shown that the macroflux is obtained from a two-group diffusion equation in which the coefficients are determined from transport cross sections and microfluxes. The relationships between microfluxes are given. It is shown that in a finite core the flux is described by an asymptotic and a transient term. A simple problem is solved by means of the presented theory, showing that it is capable of providing a truncated series expansion of the exact results. The theory presented is applied to the evaluation of measurements.