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Division Spotlight
Fusion Energy
This division promotes the development and timely introduction of fusion energy as a sustainable energy source with favorable economic, environmental, and safety attributes. The division cooperates with other organizations on common issues of multidisciplinary fusion science and technology, conducts professional meetings, and disseminates technical information in support of these goals. Members focus on the assessment and resolution of critical developmental issues for practical fusion energy applications.
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
Dragonfly, a Pu-fueled drone heading to Titan, gets key NASA approval
Curiosity landed on Mars sporting a radioisotope thermoelectric generator (RTG) in 2012, and a second NASA rover, Perseverance, landed in 2021. Both are still rolling across the red planet in the name of science. Another exploratory craft with a similar plutonium-238–fueled RTG but a very different mission—to fly between multiple test sites on Titan, Saturn’s largest moon—recently got one step closer to deployment.
On April 25, NASA and the Johns Hopkins University Applied Physics Laboratory (APL) announced that the Dragonfly mission to Saturn’s icy moon passed its critical design review. “Passing this mission milestone means that Dragonfly’s mission design, fabrication, integration, and test plans are all approved, and the mission can now turn its attention to the construction of the spacecraft itself,” according to NASA.
Aydin Karahan, Jacopo Buongiorno, Mujid S. Kazimi
Nuclear Technology | Volume 171 | Number 1 | July 2010 | Pages 38-52
Technical Paper | Thermal Hydraulics | doi.org/10.13182/NT10-A10771
Articles are hosted by Taylor and Francis Online.
The large assembly with small pins (LASP) concept is an evolutionary boiling water reactor (BWR) fuel assembly design aimed at increasing the power density of BWR cores while keeping the same power-to-flow ratio, core inlet conditions, and fuel-to-moderator ratio. It is based on replacing four traditional assemblies and their large interassembly water gap regions with a single large assembly surrounded by a narrower gap region. The traditional BWR cylindrical UO2-fueled Zr-clad fuel pin design is retained, but the pins are arranged on a 22 × 22 square lattice. Twenty-five water rods within the assembly maintain the moderating power and accommodate as many finger-type control rods. The technical characteristics of LASP were evaluated and are systematically compared with a traditional 9 × 9 fuel assembly. This design study includes analyses of the steady-state thermal hydraulics, two-dimensional and three-dimensional burnup-dependent neutronics, flow-induced vibrations, and fuel pin thermomechanical behavior. Furthermore, the conceptual mechanical design of the LASP assembly is discussed. The analyses show that LASP can operate at a power density that is 20% higher than the traditional BWR assemblies while maintaining the same safety margin.
