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Division Spotlight
Thermal Hydraulics
The division provides a forum for focused technical dialogue on thermal hydraulic technology in the nuclear industry. Specifically, this will include heat transfer and fluid mechanics involved in the utilization of nuclear energy. It is intended to attract the highest quality of theoretical and experimental work to ANS, including research on basic phenomena and application to nuclear system design.
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2024 ANS Winter Conference and Expo
November 17–21, 2024
Orlando, FL|Renaissance Orlando at SeaWorld
Standards Program
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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New laws offer nuclear industry incentives for existing power plant uprates
This year, the U.S. nuclear industry received a much-needed economic boost that could help preserve operating nuclear power plants and incentivize upgrades that extend their lifespan and power output.
Signed into law in 2022, the Inflation Reduction Act offers production tax credits (PTCs) for existing nuclear power plants and either PTCs or investment tax credits (ITCs) for new carbon-free generation. These credits could make power uprates—increasing the maximum power level at which a commercial plant may operate—a much more appealing option for utilities.
Akitoshi Hotta, Hiroshi Shirai, Shinya Mizokami
Nuclear Science and Engineering | Volume 152 | Number 3 | March 2006 | Pages 292-305
Technical Paper | doi.org/10.13182/NSE06-A2583
Articles are hosted by Taylor and Francis Online.
A postulated single control rod drop transient was calculated for a typical boiling water reactor plant taking into account effects of detailed void distributions in those bundles neighboring the withdrawn control blade. Time-dependent pin power distributions were reconstructed by the plant simulator TRAC/BF1-ENTRÉE and were exported to the subchannel code NASCA.Macroscopic cross-section libraries based on flat and distorted void distributions were allocated in accordance with fuel location in a simplified two-way coupling method. Exposure trends of bundle neutronic properties were compared between two void distributions. Although the infinite multiplication factor was not influenced, the radial peaking factor increased significantly because of the void distortion caused by pin-by-pin exposure of fissile materials.The result with the combined cross sections was compared with those with the flat void cross sections. Application of the combined cross sections lowered the initial local peaking because of larger neutron leakage around the withdrawn control blade. The transient linear power density at the critical fuel rod increased more rapidly. A change in the fuel heat flux was attenuated because of the heat conduction delay. As a consequence of these effects, the peak cladding temperature became slightly lower than that of the flat void model.