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Aerospace Nuclear Science & Technology
Organized to promote the advancement of knowledge in the use of nuclear science and technologies in the aerospace application. Specialized nuclear-based technologies and applications are needed to advance the state-of-the-art in aerospace design, engineering and operations to explore planetary bodies in our solar system and beyond, plus enhance the safety of air travel, especially high speed air travel. Areas of interest will include but are not limited to the creation of nuclear-based power and propulsion systems, multifunctional materials to protect humans and electronic components from atmospheric, space, and nuclear power system radiation, human factor strategies for the safety and reliable operation of nuclear power and propulsion plants by non-specialized personnel and more.
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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
DOE issues RFQ for clean-energy projects at WIPP
The Department of Energy has issued a request for qualifications (RFQ) for interested parties that are looking to establish carbon pollution–free electricity (CFE) projects at its Waste Isolation Pilot Plant site in New Mexico.
H. K. Cho, B. J. Yun, C.-H. Song, G. C. Park
Nuclear Science and Engineering | Volume 156 | Number 1 | May 2007 | Pages 40-54
Technical Paper | doi.org/10.13182/NSE07-A2683
Articles are hosted by Taylor and Francis Online.
In a nuclear reactor vessel downcomer incorporating the safety feature of direct vessel injection (DVI), the direct bypass of emergency core coolant (ECC) is activated during the reflood phase of a large-break loss-of-coolant accident due to momentum transfer between the downward liquid film and transverse gas. Direct ECC bypass is reportedly the major bypass mechanism of ECC, and various experiments have been performed to obtain detailed information about the ECC bypass in a DVI downcomer. In the present study, a model of the direct ECC bypass was developed based on two-dimensional two-fluid equations for the adiabatic two-phase flow to predict the ECC bypass flow rate. The direct ECC bypass fractions were calculated with various interfacial friction factor correlations, and the results were compared with the available experimental data. The values predicted by the current model showed reasonably good agreement with the experimental data at bypass fractions >40% when applying the interfacial friction factor model developed in a countercurrent flow condition. However, when the bypass fraction was <40%, models incorporating cocurrent annular flow provided better results than those with countercurrent flow. These results suggest that a transition occurs from a smooth film to a rough film as the gas flow rate increases, and hence, interfacial friction factor models that adequately incorporate this transition are necessary to predict the direct ECC bypass phenomenon.