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Division Spotlight
Materials Science & Technology
The objectives of MSTD are: promote the advancement of materials science in Nuclear Science Technology; support the multidisciplines which constitute it; encourage research by providing a forum for the presentation, exchange, and documentation of relevant information; promote the interaction and communication among its members; and recognize and reward its members for significant contributions to the field of materials science in nuclear technology.
Meeting Spotlight
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
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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Latest News
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.
Apoorva Rudra, Masahiro Kawaji (City College of New York), Aleksandr V. Obabko Saumil Patel (ANL)
Proceedings | Advances in Thermal Hydraulics 2018 | Orlando, FL, November 11-15, 2018 | Pages 694-700
Very High Temperature Reactors (VHTRs) have passive safety systems in comparison to the traditional current generation nuclear reactors that have active safety systems. In addition, they have gaseous coolants like helium proposed for them that allow them to operate at a temperature over 1000 oC along with other applications. However, several substantial engineering challenges are expected in VHTRs and can lead to localized hot spots in the reactor core as a result of degraded heat transfer in coolant channels. Our work addresses one such scenario called flow relaminarization. The following work incorporates 3D simulations in a very long pipe wherein turbulence is sustained throughout for the largest aspect ratio (L/D ratio) known in literature (~235). This work is the first step of a two-step process towards the final objective of studying heat driven turbulent gas relaminarization. Simulations are performed using a high order, spectral element and massively parallel CFD code called NEK5000 that combines the geometric flexibility of finite elements with the high accuracy of spectral methods. A replication method along with recycled periodicity is incorporated to successfully sustain turbulence throughout the pipe. The maximum Reynolds number incorporated for these simulations is 5190 which is chosen keeping in mind the flow relaminarization (forced convection) experiments that were performed by the group in the past. A sensitivity study on the polynomial order was performed as well and based on that the polynomial order chosen for the simulations was 6.