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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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International Conference on Mathematics and Computational Methods Applied to Nuclear Science and Engineering (M&C 2025)
April 27–30, 2025
Denver, CO|The Westin Denver Downtown
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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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Argonne’s METL gears up to test more sodium fast reactor components
Argonne National Laboratory has successfully swapped out an aging cold trap in the sodium test loop called METL (Mechanisms Engineering Test Loop), the Department of Energy announced April 23. The upgrade is the first of its kind in the United States in more than 30 years, according to the DOE, and will help test components and operations for the sodium-cooled fast reactors being developed now.
Yiban Xu, Robert A. Brewster, Michael E. Conner, Zeses E. Karoutas, L. David Smith, III
Nuclear Technology | Volume 205 | Number 1 | January-February 2019 | Pages 57-67
Technical Paper | doi.org/10.1080/00295450.2018.1510265
Articles are hosted by Taylor and Francis Online.
Critical heat flux (CHF) is a primary parameter for nuclear fuel design and plant operation safety. CHF values are normally obtained from fuel bundle integral departure from nucleate boiling (DNB) or dryout experiments. These experiments are expensive, and detailed measurements (bubble dynamics, void fraction distribution, etc.) are difficult to obtain, particularly under typical pressurized water reactor (PWR) conditions of high pressure and temperature. Therefore, it is highly desirable that computational tools such as computational fluid dynamics (CFD) provide detailed flow and heat transfer information that will efficiently facilitate design improvements of PWR fuel designs.
For the CFD studies described in this paper, an Eulerian-Eulerian two-phase modeling approach was adopted to predict DNB in a fuel assembly with mixing vane grids. Subcooled flow boiling was simulated using heat flux partition modeling and phase interactions. Direct addition of heat to the vapor was activated when the local vapor volume fraction reached a specified critical value. Emphases were placed on bubble departure diameter, phase interactions, and pressure drop for two-phase modeling development. Simulations were conducted in steady state. Solution convergence was closely monitored for physical variables in terms of local and global scales. A multi-indicator approach was used to judge DNB occurrence, and a new integrated DNB indicator is proposed.
For validation, this CFD-based DNB modeling methodology was applied to two 5 × 5 rod bundle tests equipped with mixing vane grids and uniform axial power shape. The tests were performed under PWR conditions (16.5 MPa) and produced an exit quality of −4% and 11%. The CFD results show the validity of the new DNB indicator and the improved reliability with the multi-indicator approach. Correctly predicted DNB occurrence locations show the promise of the current modeling approach. Utilization of measured pressure drop and fluid temperature data may permit some bottom-up validations, and this effort may prompt further improvements for experimental measurements, particularly under high-pressure conditions.