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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.
I. Dilber and E. E. Lewis
Nuclear Science and Engineering | Volume 91 | Number 2 | October 1985 | Pages 132-142
Technical Paper | doi.org/10.13182/NSE85-A27436
Articles are hosted by Taylor and Francis Online.
Nodal diffusion and transport methods are formulated variationally in terms of the even-parity form of the neutron transport equation and applied to problems in X-Y geometry. The resulting functional guarantees the satisfaction of nodal balance, regardless of the form of the space-angle trial function within the node or on its boundaries. Deletion of X-Y cross terms from the within-node flux approximations yields equations that are strikingly similar to conventional diffusion nodal methods; inclusion of the terms obviates ad hoc approximations to the transverse leakage. Transport and diffusion nodal methods differ only in the angular basis functions. In both cases the equations are first solved for partial current moments along nodal interfaces. Subsequently, the detailed flux distribution and the node-averaged scalar flux values are obtained from the spatial trial functions. Results are given for fixed-source two-dimensional problems in the P1 and P3 approximations. Code vectorization and generalization to three dimensions are discussed.