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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.
V. G. Molinari, L. Pollachini
Nuclear Science and Engineering | Volume 91 | Number 4 | December 1985 | Pages 458-469
Technical Note | doi.org/10.13182/NSE85-A18362
Articles are hosted by Taylor and Francis Online.
A set of equations that describes the diffusion of thermal neutrons is obtained from the energy-dependent Boltzmann equation. These equations are analogous to the phenomenological laws of the thermodynamic theory of irreversible processes and show, for instance, that as a temperature gradient produces a neutron current (Soret effect), a density gradient yields an energy flow (Dufour effect). The method is applied to the “two-temperature problem” in order to gain better insight into the thermal diffusion phenomenon. The thermal diffusion of neutrons is shown to strongly depend on the scattering law of the two media where neutrons diffuse, and it is determined that some of the conclusions previously obtained are valid only for the case of a heavy gas moderator with the scattering cross section independent of the energy.