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Reactor Physics
The division's objectives are to promote the advancement of knowledge and understanding of the fundamental physical phenomena characterizing nuclear reactors and other nuclear systems. The division encourages research and disseminates information through meetings and publications. Areas of technical interest include nuclear data, particle interactions and transport, reactor and nuclear systems analysis, methods, design, validation and operating experience and standards. The Wigner Award heads the awards program.
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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
X-energy receives federal tax credit for TRISO fuel facility
Advanced reactor company X-energy has been awarded $148.5 million in tax credits under the Inflation Reduction Act for construction of its TRISO-X fuel fabrication facility in Oak Ridge, Tenn.
Faith R. Beck, Yue Jin, Fan-Bill Cheung (Penn State), Stephen M. Bajorek, Kirk Tien, Chris L. Hoxie (NRC)
Proceedings | Advances in Thermal Hydraulics 2018 | Orlando, FL, November 11-15, 2018 | Pages 739-750
In a large break loss of coolant accident (LOCA) in a pressurized water reactor (PWR), a break may occur on one of the cold legs. The emergency core cooling system (ECCS) must provide sufficient coolant to the core to remove decay heat and prevent the cladding from exceeding 1477.6 K. During reflood, flow to the core is most often gravity driven, resulting in an oscillatory delivery of coolant to the core. These oscillations are attributed to vapor generation in the core and the dynamic response of the downcomer water level. The amount of liquid entrained can be significant because in an accident scenario, the progress rate will be slowed and it can take longer to fully recover the core. Most reflood experiments have been conducted with constant forced reflood rates, and have not explored in detail the effects of oscillations on liquid entrainment and rod bundle heat transfer. The few studies that have been conducted for oscillating flows indicate enhanced entrainment of liquid at the quench front. At the NRC-PSU Rod Bundle Heat Transfer (RBHT) Test Facility, an electrically heated 7×7, 3.66m long rod bundle array has the capabilities to perform both constant and oscillatory forced flooding rate experiments. For varying oscillation periods and inlet subcoolings, these system parameters’ effect the liquid entrainment has been analyzed. Using a frequency analysis and signal processing technique, the percent liquid entrainment has been determined in one up- or down-stroke for oscillatory reflood. These findings, which are important to rod bundle heat transfer during reflood transients, have been explained based on the physics of the problem.