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Division Spotlight
Materials Science & Technology
The objectives of MSTD are: promote the advancement of materials science in Nuclear Science Technology; support the multidisciplines which constitute it; encourage research by providing a forum for the presentation, exchange, and documentation of relevant information; promote the interaction and communication among its members; and recognize and reward its members for significant contributions to the field of materials science in nuclear technology.
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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Nuclear Science and Engineering
August 2024
Nuclear Technology
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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 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. 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.”
D. B. Lancaster, K. S. Smith, A. J. Machiels
Nuclear Technology | Volume 185 | Number 1 | January 2014 | Pages 57-70
Technical Paper | Fuel Cycle and Management | doi.org/10.13182/NT13-28
Articles are hosted by Taylor and Francis Online.
The Electric Power Research Institute (EPRI) has sponsored the development of a set of benchmarks that can be used to quantify the bias and uncertainty in computed reactivity decrements due to burnup. The bias and uncertainty covers imprecision in both the nuclide inventory and cross sections. The EPRI benchmarks are a function of enrichment, operating conditions (such as soluble boron concentration, burnable absorbers, and specific power), and storage rack conditions. The benchmarks are analyzed using SCALE 6.1 with both ENDF/B-V and ENDF/B-VII cross-section libraries. The depletion analyses are performed using the TRITON module, and the criticality calculations are performed with KENO-V.a and MCNP. The analysis shows that SCALE 6.1 with the ENDF/B-VII 238-group cross-section library supports the use of a depletion bias of only 0.0015 in Δk, where k represents the neutron multiplication factor, at peak reactivity after discharge from the core. This peak reactivity occurs after 100 h of cooling. If credit is taken for more cooling, the bias should be increased to 0.0025. The depletion uncertainty is 0.0064. Using MCNP for the criticality calculations rather than KENO-V.a produces essentially the same results if the same ENDF/B cross-section library is used. Reliance on the ENDF/B-V cross-section library produces much larger disagreement with the benchmarks. The analysis covers numerous combinations of depletion and criticality options. In all cases, the historical uncertainty of 5% of the Δk of depletion (“Kopp memo”) was shown to be conservative for fuel with >30 GWd/T burnup. However, the Kopp memo's uncertainty may be exceeded at low burnups where the absolute magnitude of the uncertainty is small.