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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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2024 ANS Annual Conference
June 16–19, 2024
Las Vegas, NV|Mandalay Bay Resort and Casino
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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
College students help develop waste-measuring device at Hanford
A partnership between Washington River Protection Solutions (WRPS) and Washington State University has resulted in the development of a device to measure radioactive and chemical tank waste at the Hanford Site. WRPS is the contractor at Hanford for the Department of Energy’s Office of Environmental Management.
Hideki Kamide, Jun Kobayashi, Kenji Hayashi
Nuclear Technology | Volume 175 | Number 3 | September 2011 | Pages 628-640
Technical Paper | NURETH-13 Special / Fission Reactors | doi.org/10.13182/NT11-A12511
Articles are hosted by Taylor and Francis Online.
Natural circulation plays a significant role in the decay heat removal function of a sodium-cooled reactor. A recent design of the Japan Sodium-Cooled Fast Reactor (JSFR) fully uses natural circulation for a decay heat removal system (DHRS). A dipped heat exchanger (DHX) is immersed in the reactor upper plenum as the DHRS. The DHX provides cold sodium in the upper plenum during the decay heat removal operation. This cold sodium covers the top of the core under the low-flow-rate conditions of natural circulation. Several water experiments of natural circulation in fast reactors revealed that the cold fluid in the reactor upper plenum might partially and temporally penetrate into the low power core channels, e.g., the radial blanket fuel subassemblies. Sodium experiments were carried out to find the onset conditions and the penetration depth of such partial reverse flow driven by buoyancy force. A blanket subassembly and the upper plenum were modeled in the test section including the axial upper neutron shielding of the subassembly. The experimental parameters were the temperature difference between the hot upward flow in the channel and the cold fluid in the upper plenum and the flow velocity in the channel. The onset conditions of the penetration flow were correlated with Gr and Re numbers as well as with basic water experiments. The observed penetration depths were limited to the upper axial neutron shielding of the subassembly.