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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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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
Nano Nuclear wins Air Force contract for Kronos MMR
New York City–based advanced nuclear technology developer Nano Nuclear Energy has been awarded a Direct-to-Phase II Small Business Innovation Research contract for its Kronos micro modular reactor (MMR) by AFWERX, the innovation and venture arm of the U.S. Air Force. The contract calls for AFWERX, with the 11th Civil Engineering Squadron, to explore the feasibility of deploying the Kronos MMR Energy System at Joint Base Anacostia-Bolling (JBAB) in Washington, D.C.
Cheng Peng, Youya Song, Jian Deng, Sen Mao, Jiang Wu
Nuclear Science and Engineering | Volume 197 | Number 6 | June 2023 | Pages 1117-1132
Technical Paper | doi.org/10.1080/00295639.2022.2143208
Articles are hosted by Taylor and Francis Online.
Third-generation advanced pressurized water reactors adopt the external reactor vessel cooling (ERVC) strategy to ensure the pressure vessel is not at risk of melt-through in severe accidents, thereby completely controlling radioactive materials in the pile. However, due to its long-term service, vessel aging, steel corrosion, and oxidation may lead to deformation at different locations on its outer surface, forming various shapes of sawtooth structures, thus affecting the heat transfer behavior of the high-temperature walls during ERVC. In this paper, the Fluent code, coupled with boiling heat and mass transfer equations based on user-defined functions (UDFs) was used to simulate the thermal-hydraulic processes on the lower head with three typical sawtooth structures. The distribution of the stagnation zone for vapor buildup was the main focus. By varying the heat flux installed on the lower head and the inlet velocity of the flow channel, the onset time of critical boiling and the development of the location of critical heat flux over time were further investigated. It was found that a long period of unstable bubble generation and detachment before the onset of critical boiling may occur on the lower head. These findings can provide technical support for the safety design of advanced nuclear reactors.