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Decommissioning & Environmental Sciences
The mission of the Decommissioning and Environmental Sciences (DES) Division is to promote the development and use of those skills and technologies associated with the use of nuclear energy and the optimal management and stewardship of the environment, sustainable development, decommissioning, remediation, reutilization, and long-term surveillance and maintenance of nuclear-related installations, and sites. The target audience for this effort is the membership of the Division, the Society, and the public at large.
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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.”
David D. B. van Bragt, Tim H. J. J. van der Hagen
Nuclear Technology | Volume 121 | Number 1 | January 1998 | Pages 52-62
Technical Paper | Reactor Safety | doi.org/10.13182/NT98-A2818
Articles are hosted by Taylor and Francis Online.
A parametric study of coupled neutronic-thermohydraulic stability of natural circulation boiling water reactors (BWRs) is performed. As an example, the stability characteristics of the Dutch Dodewaard reactor, which was cooled by natural circulation, are determined. The Dodewaard reactor can be considered as the prototype of next generation natural circulation BWRs. The stability issues that are identified for this prototype reactor are therefore important in the design of new natural circulation BWRs.Without a riser section installed, only one region of thermohydraulic instability exists in the stability plane. The significant gravitational pressure drop in a riser section, installed to enhance the natural circulation flow, gives rise to the emergence of an additional region of instability. The oscillations in this zone become especially important during low-power/low-pressure (reactor startup) conditions. Significant damping of these oscillations occurs in a reactor, due to the nuclear void reactivity feedback.A comparison between natural circulation in-phase and out-of-phase reactor stability is made, in particular important for large reactor cores but also yielding unexpected results for small reactors. The impact of downcomer inertia on the stability of the in-phase mode is investigated in detail. Typical trajectories in the dimensionless stability plane are calculated as a function of changing operating conditions, to investigate their influence on reactor dynamics.