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Division Spotlight
Nuclear Criticality Safety
NCSD provides communication among nuclear criticality safety professionals through the development of standards, the evolution of training methods and materials, the presentation of technical data and procedures, and the creation of specialty publications. In these ways, the division furthers the exchange of technical information on nuclear criticality safety with the ultimate goal of promoting the safe handling of fissionable materials outside reactors.
Meeting Spotlight
International Conference on Mathematics and Computational Methods Applied to Nuclear Science and Engineering (M&C 2025)
April 27–30, 2025
Denver, CO|The Westin Denver Downtown
Standards Program
The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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Latest News
DTE Energy studying uprate at Fermi-2, considers Fermi-3’s prospects
DTE Energy, the owner of Fermi nuclear power plant in Michigan, is considering an extended uprate for Unit 2 that would increase its 1,100-MW generation capacity by 150 MW.
Jacques Rognon
Nuclear Science and Engineering | Volume 30 | Number 1 | October 1967 | Pages 109-121
Technical Paper | doi.org/10.13182/NSE67-A17248
Articles are hosted by Taylor and Francis Online.
In this paper fast-fission effects in lattices with cluster elements are treated by dividing the cluster into concentric annuli and homogenizing each ring by means of the subcell method. Each annular zone is analyzed separately, and the influence of neighboring zones is described by in- and out-currents at the zone boundaries. Consistency of cross sections is checked in the simple case of an isolated rod in air. Backscattering and cluster-cluster interaction effects are taken into account and an extensive comparison is made between theoretical and experimental fission ratios. Finally, a new definition of ε is proposed, which is more consistent with the definition of p and combines all fast events in ε . EPSICH, a program based on this theory, calculates a complete case in a few tenths of a second on a CDC-1604, which justifies its use for optimalization studies.
