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Radiation Protection & Shielding
The Radiation Protection and Shielding Division is developing and promoting radiation protection and shielding aspects of nuclear science and technology — including interaction of nuclear radiation with materials and biological systems, instruments and techniques for the measurement of nuclear radiation fields, and radiation shield design and evaluation.
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Utility Working Conference and Vendor Technology Expo (UWC 2024)
August 4–7, 2024
Marco Island, FL|JW Marriott Marco Island
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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.”
Soo-Yong Park, Young-Ho Jin, Yong-Mann Song
Nuclear Technology | Volume 158 | Number 1 | April 2007 | Pages 109-115
Technical Note | Thermal Hydraulics | doi.org/10.13182/NT07-A3829
Articles are hosted by Taylor and Francis Online.
An external reactor vessel cooling as a means for an in-vessel retention has been selected as one of the tentative severe accident management strategies for the Wolsong plants, which are typical CANDU 6 reactors. The strategy takes advantage of the plant-specific features: (a) the power density is low, (b) the calandria vessel and the calandria vault have large water volumes, (c) the calandria is always submerged in the water of the calandria vault during a normal operation, (d) the stainless steel layer of the molten corium is negligible even though the unoxidized Zircaloy could form a metal layer, (e) no insulation structure is designed around the calandria vessel, (f) the bottom area of the calandria is large enough to transfer a sufficient amount of the corium decay heat into the calandria vault water, and (g) the water supply from the backup water sources into the calandria vault is available for a long-term external cooling of the calandria. The above design features cause a severe accident progression to be considerably delayed, and they minimize the in-vessel retention issues applied to a certain pressurized light water reactor. Furthermore, the thermal analysis demonstrates that the molten corium on the bottom of the calandria is externally coolable in terms of the critical heat flux, although phenomenological uncertainties still exist. This paper shows the feasibility and the evaluation results of the in-vessel retention strategy via an external vessel cooling for the CANDU 6-type plants, which have not been addressed as yet.