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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
Utility Working Conference and Vendor Technology Expo (UWC 2024)
August 4–7, 2024
Marco Island, FL|JW Marriott Marco Island
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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Fusion Science and Technology
Latest News
Vogtle-3 shuts down for valve issue
One of the new Vogtle units in Georgia was shut down unexpectedly on Monday last week for a valve issue that has since been investigated and repaired. According to multiple local news outlets, Georgia Power reported on July 17 that Unit 3 was back in service.
Southern Company spokesperson Jacob Hawkins confirmed that Vogtle-3 went off line at 9:25 p.m. local time on July 8 “due to lowering water levels in the steam generators caused by a valve issue on one of the three main feedwater pumps.”
Robert C. Ward, Don Steiner
Fusion Science and Technology | Volume 33 | Number 2 | March 1998 | Pages 210-217
Technical Paper | doi.org/10.13182/FST98-A29
Articles are hosted by Taylor and Francis Online.
The impact and status of the cross sections for production of short-lived radioactivities in the intense high-energy neutron fields associated with deuterium-tritium fusion reactors is investigated. The main concern relative to these very radioactive species is that they may represent enhanced radiation sources not accounted for in typical transport calculations. These enhanced radiation sources may affect heat removal and shielding requirements. The status of nuclear data required to assess these issues is surveyed. Among the factors considered in defining the relevant reactions and setting priorities are quantities of the elemental materials in a fusion reactor, isotopic abundances within elemental categories, the decay properties of the induced radioactive by-products, the reaction cross sections, and the nature of the decay radiations. Attention has been focused on radioactive species with half-lives in the range from ~1 s to 15 min. Available cross-section and reaction-product decay information from the literature are compiled and examined. The evaluated data sets are collapsed using neutron spectra from three fusion reactor designs - ARIES I and II and the International Thermonuclear Experimental Reactor (ITER). The group-averaged cross-section sets are then used to produce neutron-spectrum-averaged, one-group cross sections, which are, in turn, used to produce decay heating reaction rates for each of the reactions. The decay heating rate is used as a measure of the radiation source strength associated with a given reaction. The decay heating reaction rates are compared against neutron heating reaction rates. Calculated decay heat to neutron heating ratios are required to be >10% in order for the reaction to be considered of importance for further study. The reactions of importance are identified as 28Si(n,p)28Al, with a ratio of ~10%, and 207Pb(n,n')207mPb, with a ratio >50%. The 28Si(n,p)28Al reaction could affect heat removal requirements for reactors employing silicon carbide as a structural material. The 207Pb(n,n')207mPb reaction could affect heat removal and shielding requirements for shield designs employing lead. Identified reactions of slightly less importance are 27Al(n,p)27Mg, 9Be(n,)6He, 52Cr(n,p)52V, 16O(n,p)16N, and 204Pb(n,2n)203mPb - all of which have ratios between 1 and 4%.