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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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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 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.”
Dong-Kwon Keum, Chung-Kyun Park, Pil-Soo Hahn, Tjalle T. Vandergraaf
Nuclear Technology | Volume 120 | Number 3 | December 1997 | Pages 211-223
Technical Paper | Radioactive Waste Management | doi.org/10.13182/NT97-A35412
Articles are hosted by Taylor and Francis Online.
Modifications have been made to an existing stratified channel contaminant transport model by incorporating hydrodynamic dispersion in each channel. The integrals in the modified model are solved by a numeric method. Gaussian quadrature integration formulas were used to solve the equation, including the Gauss-Laguerre quadrature to deal with the upper infinite limit of the integral. This approach proved to be both accurate and efficient. The effects of physicochemical parameters on the elution breakthrough curve have been studied with this model. The parameters that were considered were (a) the standard deviation of a lognormal distribution of the channel width, (b) longitudinal dispersivity, (c) water velocity, (d) fracture length, (e) surface sorption coefficient, and (f) rock matrix diffusivity. Results from the calculations showed that the hydrodynamic dispersion in each channel caused additional dispersion in the elution profile. A new parameter, which quantifies rock matrix dif fusion and residence time of the solute in the fracture simultaneously, and its reference value are presented. This parameter is useful to determine numerically if the diffusion into the rock matrix is a significant contribution to the transport of the tracer through the fracture. This parameter can also be used in the design of migration experiments intended to observe diffusion into the rock matrix. The modified model has been used to analyze two independent experimental data sets obtained for a conservative tracer, one obtained in an artificial fracture and the other in a natural fracture. The results obtained with this modified model were in good agreement with both sets of experimental results. The dispersivities for both experimental systems were determined by curve fitting, and similar values were obtained for both types of fracture. The values obtained for the natural fracture especially indicated that both local hydrodynamic and channeling dispersion occurred.