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Fuel Cycle & Waste Management
Devoted to all aspects of the nuclear fuel cycle including waste management, worldwide. Division specific areas of interest and involvement include uranium conversion and enrichment; fuel fabrication, management (in-core and ex-core) and recycle; transportation; safeguards; high-level, low-level and mixed waste management and disposal; public policy and program management; decontamination and decommissioning environmental restoration; and excess weapons materials disposition.
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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.
Henry A. Sandmeier
Nuclear Science and Engineering | Volume 9 | Number 2 | February 1961 | Pages 260-270
doi.org/10.13182/NSE61-A15608
Articles are hosted by Taylor and Francis Online.
To test reactor fuel elements for their content of fissionable material and poison, it is desirable to have an assembly which has maximum sensitivity to a perturbation of fissionable absorber in the axial center line of the reactor. For normal sizes of thermal power reactor fuel elements, a graphite-moderated reactor is a suitable choice. The change in reactivity measured is the difference between the effect of changes in the fission and absorption parameters. For a bare core and uniform fuel distribution, maximum sensitivity to a fission-parameter-perturbation is obtained for a reactor which has a minimum critical mass. Maximum sensitivity to an absorber-parameter-perturbation is obtained for a reactor which has a minimum amount of total absorptions. Both the fission and absorption sensitivity reach a maximum when the critical mass is minimum. For a reflected core and uniform fuel distribution, the sensitivity to a fissionable absorber can be increased 22% over the bare core sensitivity. By introducing an internal and external reflector, the sensitivity to a fissionable absorber can be increased 30% over the externally reflected core and 56% over the bare core. For nonuniform fuel distribution, an expression is derived relating the effect of a perturbation in fission and absorption to reactivity. The problem of finding a fuel distribution ψ(r) to maximize this expression is analytically formulated. A parameter study was made for the same reactors as for the uniform fuel distribution cases. This was done by shifting more fuel towards the center or towards the edge of the core. No gain in fissionable absorber sensitivity was observed for either the bare or the externally reflected cores. However, the internally and externally reflected core showed a 10% increase in fissionable absorber sensitivity when more fuel was shifted towards the center.
