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Division Spotlight
Operations & Power
Members focus on the dissemination of knowledge and information in the area of power reactors with particular application to the production of electric power and process heat. The division sponsors meetings on the coverage of applied nuclear science and engineering as related to power plants, non-power reactors, and other nuclear facilities. It encourages and assists with the dissemination of knowledge pertinent to the safe and efficient operation of nuclear facilities through professional staff development, information exchange, and supporting the generation of viable solutions to current issues.
Meeting Spotlight
2024 ANS Winter Conference and Expo
November 17–21, 2024
Orlando, FL|Renaissance Orlando at SeaWorld
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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Keeping up with Kewaunee
In October 2012, Dominion Energy announced it was closing the Kewaunee nuclear power plant, a two-loop 574-MWe pressurized water reactor located about 27 miles southeast of Green Bay, Wis., on the western shore of Lake Michigan. At the time, Dominion said the plant was running well, but that low wholesale electricity prices in the region made it uneconomical to continue operation of the single-unit merchant power plant.
H. Feshbach, G. Goertzel, H. Yamauchi
Nuclear Science and Engineering | Volume 1 | Number 1 | March 1956 | Pages 4-19
Technical Paper | doi.org/10.13182/NSE56-A17654
Articles are hosted by Taylor and Francis Online.
The detailed variation with energy of that part of the neutron cross section of an element which shows resonance behavior is temperature dependent. This dependence, the Doppler effect, arises from the temperature variation of neutron-nuclear relative velocity distribution. An effective cross section (dependent on reactor composition) useful in reactor calculations in place of the rapidly fluctuating actual cross section is defined. Knowledge of the variation of this effective cross section with material temperature is needed for calculation of the temperature coefficient of reactivity. Unfortunately, resolution of present measuring equipment does not permit sufficiently accurate measurement of cross sections in the energy range of interest in fast reactors (100 kev to several Mev), for Doppler effect calculation nor are direct measurements in this energy range available at present. To estimate Doppler effect, it has been assumed that in any energy range containing many resonances the actual cross section is equivalent, as far as reactor behavior is concerned, to a cross section constructed by selecting spacings between neighboring resonances and other resonance parameters independently from probability distributions of these parameters. In this manner, temperature coefficients may be calculated in terms of measured cross sections and various statistical parameters of the probability distributions, the parameters being estimated from low-energy data on actual resonances. In applying the low-energy data to the energy ranges of interest, the predictions of the statistical model of the nucleus, as developed by Weisskopf and others, are employed.