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Division Spotlight
Fuel Cycle & Waste Management
Devoted to all aspects of the nuclear fuel cycle including waste management, worldwide. Division specific areas of interest and involvement include uranium conversion and enrichment; fuel fabrication, management (in-core and ex-core) and recycle; transportation; safeguards; high-level, low-level and mixed waste management and disposal; public policy and program management; decontamination and decommissioning environmental restoration; and excess weapons materials disposition.
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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.”
Yutaka Takeuchi, Yukio Takigawa, Shiho Miyamoto
Nuclear Technology | Volume 128 | Number 2 | November 1999 | Pages 257-275
Technical Paper | Reactor Safety | doi.org/10.13182/NT99-A3030
Articles are hosted by Taylor and Francis Online.
A methodology for boiling water reactor (BWR) regional stability with a one-point neutron kinetics model is proposed from the higher harmonics viewpoint and is verified with the Ringhals-1 stability benchmark test data. A one-point neutron kinetics model for regional stability analysis is derived from the spatial neutron diffusion equation using the mode decomposition technique. From the derivation, the intermode coupled reactivity coefficient is defined and applied to a frequency-domain BWR stability analysis model. The analysis model traces a unit power perturbation and calculates the open-loop transfer function as the power response to the input perturbation. Combined with the aforementioned reactivity coefficient and the asymmetric shape perturbation that reflects the first azimuthal mode, the first azimuthal mode is excited exclusively without any assumption on the ex-core model. Therefore, the regional stability can be evaluated with a normal recirculation flow model, which is employed for core-wide stability analysis. The methodology is verified with the Ringhals-1 stability benchmark test data, whose stability conditions were widely distributed and suitable for verification. The results show that the proposed methodology is quite appropriate for BWR regional stability analysis.