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Mathematics & Computation
Division members promote the advancement of mathematical and computational methods for solving problems arising in all disciplines encompassed by the Society. They place particular emphasis on numerical techniques for efficient computer applications to aid in the dissemination, integration, and proper use of computer codes, including preparation of computational benchmark and development of standards for computing practices, and to encourage the development on new computer codes and broaden their use.
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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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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.”
Young Min Kwon, Chan Eok Park, Jin Ho Song
Nuclear Technology | Volume 122 | Number 3 | June 1998 | Pages 295-305
Technical Paper | Thermal Hydraulics | doi.org/10.13182/NT98-A2871
Articles are hosted by Taylor and Francis Online.
To investigate the realistic behavior of mass and energy release and resultant containment response during a large-break loss-of-coolant accident (LOCA), analyses are performed on the Yonggwang (YGN) 3&4 nuclear power plants using the RELAP5/CONTEMPT4 computer code. Comparative analyses using conservative design computer codes are also performed. The break types analyzed are the double-ended guillotine breaks at the cold leg and hot leg. The design analysis predicts that the containment peak pressure occurs during the postblowdown phase for the cold-leg break. However, RELAP5/CONTEMPT4 analyses show that the containment pressure has a peak during the blowdown phase, thereafter it decreases monotonously without the postblowdown peak. For the hot-leg break, revised design analysis shows a much lower pressure than that reported in the YGN 3&4 final safety analysis report. The RELAP5/CONTEMPT4 analysis shows a similar trend and confirms that the bypass flow through the broken loop steam generator during postblowdown is negligibly small compared to that of the cold-leg break. In conclusion, realistic analysis by RELAP5/CONTEMPT4 demonstrates that the containment peak pressure occurs during the blowdown phase for both cold- and hot-leg large-break LOCAs, and there is no physical mechanism resulting in mass and energy discharge that can pressurize the containment after end of blowdown for a hot-leg break. Also, it is suggested that the substantial conservatism included in the design analysis should be improved to provide benefits in relaxing the plant technical specifications and reducing the containment design pressure.