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Fusion Energy
This division promotes the development and timely introduction of fusion energy as a sustainable energy source with favorable economic, environmental, and safety attributes. The division cooperates with other organizations on common issues of multidisciplinary fusion science and technology, conducts professional meetings, and disseminates technical information in support of these goals. Members focus on the assessment and resolution of critical developmental issues for practical fusion energy applications.
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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.”
M. A. Hoffman, A. S. Blum
Fusion Science and Technology | Volume 1 | Number 2 | April 1981 | Pages 275-284
Technical Paper | Fusion | doi.org/10.13182/FST81-A19929
Articles are hosted by Taylor and Francis Online.
The conceptual design of a vacuum pumping system to handle a large gas flow on the order of 2.31 Pa m3/s (17.3 standard (std) Torr/s) of helium gas in the pressure range from ∼ 3.1 × 10−2 down to 4.0 × 10−4 Pa (2.3 × 10−4 down to 3 × 10−6Torr) is described. The neutral helium gas originates partly as leakage from the plasma ion source and partly as additional gas required in the neutralizer duct of the neutral beam injector. The vacuum pumping design is based on the recently demonstrated process of cryotrapping the helium in a frost layer of argon formed by spraying the argon onto a liquid-helium-cooled cryopanel surface. About 10.6 m2 of cryopanel area in the ducts and chambers of the injector is required for an allowed frost thickness of 1 mm. The design is based on preliminary experimental results that indicated that ∼15 atoms of argon were needed to pump and cryotrap each helium atom, and that the specific pumping speed of the fully baffled cryopanels would be ∼31.5 std m3/m2⋅s (3.15 std⋅FS./cm2⋅s). Preliminary estimates of costs indicate that this vacuum system can cost as much as 74% of the entire neutral beam injector and that the LHe cryo-refrigerator alone can cost 24% of the total direct cost. The design points up the problem areas of cryotrapping helium and the need for clever new design concepts and improved performance to reduce costs.