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Division Spotlight
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.
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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May 2025
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.
Rei Kimura, Shohei Kanamura, Yuya Takahashi, Kazuhito Asano
Nuclear Technology | Volume 207 | Number 11 | November 2021 | Pages 1784-1792
Regular Technical Paper | doi.org/10.1080/00295450.2020.1843953
Articles are hosted by Taylor and Francis Online.
The small modular reactor (SMR) is considered one of the important energy sources for the realization of the de-carbonated society, especially SMR types that have 10 MW or less thermal power, called a microreactor or very small modular reactor (vSMR). Toshiba Energy Systems & Solutions has initiated the development of a multipurpose vSMR as a distributed energy source since 2017 called MoveluXTM (Mobile-Very-small reactor for Local Utility in X-mark).
In the current core design, a passive reactivity control device is required from the viewpoint of passive nuclear safety and operational cost reduction. The fundamental idea of vSMR passive reactivity control devices is based on the lithium expansion module (LEM) proposed by Kambe, et al. [“Startup Sequence of RAPID-L Fast Reactor for Lunar Base Power System,” Proc. Space Nuclear Conference, (2007)], however, the LEM has some issues regarding the lithium neutron absorber, such as production costs, chemical reactivity, and tritium generation. In the present study, the In-Gd alloy is proposed as an alternative to 6Li.
The In-Gd alloy is chemically stable in the air atmosphere; additionally, indium and gadolinium have enough neutron absorption cross section without isotope enrichment. However, the density, thermal expansion, and exothermal heat characteristics are not available, which is important information from the viewpoint of neutronics and safety. Hence, the material properties in the In-Gd alloy were measured, such as temperature-dependent density and chemical reactivity. Furthermore, control rod reactivity worth was evaluated based on the measured density.
As a result, the 1 wt% gadolinium contained in the In-Gd alloy shows control rod reactivity worth that is 2.5 times greater than natural lithium. Furthermore, the uncertainty of the In-Gd alloy density has a small impact on the reactivity worth; only in the range of 78 pcm (equivalent to 1% of insertion position) in the case of the 0.1 g/cm3 perturbation of the In-Gd alloy density. In conclusion, the present study shows the advantage and feasibility of the In-Gd alloy as a liquid neutron absorber for the Indium-Gadolinium Expansion Module.
