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Nuclear Nonproliferation Policy
The mission of the Nuclear Nonproliferation Policy Division (NNPD) is to promote the peaceful use of nuclear technology while simultaneously preventing the diversion and misuse of nuclear material and technology through appropriate safeguards and security, and promotion of nuclear nonproliferation policies. To achieve this mission, the objectives of the NNPD are to: Promote policy that discourages the proliferation of nuclear technology and material to inappropriate entities. Provide information to ANS members, the technical community at large, opinion leaders, and decision makers to improve their understanding of nuclear nonproliferation issues. Become a recognized technical resource on nuclear nonproliferation, safeguards, and security issues. Serve as the integration and coordination body for nuclear nonproliferation activities for the ANS. Work cooperatively with other ANS divisions to achieve these objective nonproliferation policies.
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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.
Antonio F. Dias, Laurance D. Eisenhart, Diane M. Bell, Terry J. Garrett, Glenn J. Neises, Lance J. Agee
Nuclear Technology | Volume 100 | Number 2 | November 1992 | Pages 193-202
Technical Paper | Nuclear Reactor Safety | doi.org/10.13182/NT92-A34742
Articles are hosted by Taylor and Francis Online.
The steamline break accident is one of several specified severe transients addressed in the final safety analysis report for any pressurized water reactor plant as part of the licensing procedure. A rupture in a main steamline in the secondary system causes a sudden cooling of the water in the corresponding primary loop. The cold water flowing into part of the core represents a positive reactivity insertion that must be contained by control rods, which are scrammed into the core almost immediately. Later in the scenario, soluble boron reaches the core from the emergency core cooling system. When simulating a steamline break accident during the licensing procedure, many conservative assumptions are added to the transient description. Historically, a steamline break analysis is performed with a system analysis code like RETRAN, using a rather simplified (point kinetics) description of the core. The three-dimensionality of the event within the core is accounted for by constant “blending factors,” which are used to calculate the evolving point kinetics parameters based on a simplistic cold and hot partition of the core. The ARROTTA-01 and VIPRE-02 computer codes are coupled to allow a detailed three-dimensional simulation of the reactor core during a steamline break event. The results show that a much milder transient is observed than when a point kinetics treatment was used. Test cases study the influence of different core modeling considerations on the overall simulation. The advent of very fast and extremely affordable computing machines (e.g., workstations) should cause the review of some of the simplified approaches initially adopted for many core simulations. More complex and detailed codes can now be routinely employed.