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Division Spotlight
Young Members Group
The Young Members Group works to encourage and enable all young professional members to be actively involved in the efforts and endeavors of the Society at all levels (Professional Divisions, ANS Governance, Local Sections, etc.) as they transition from the role of a student to the role of a professional. It sponsors non-technical workshops and meetings that provide professional development and networking opportunities for young professionals, collaborates with other Divisions and Groups in developing technical and non-technical content for topical and national meetings, encourages its members to participate in the activities of the Groups and Divisions that are closely related to their professional interests as well as in their local sections, introduces young members to the rules and governance structure of the Society, and nominates young professionals for awards and leadership opportunities available to members.
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.
Jin Ho Song, Sang Baik Kim, Hee Dong Kim
Nuclear Technology | Volume 138 | Number 1 | April 2002 | Pages 79-89
Technical Note | Thermal Hydraulics | doi.org/10.13182/NT02-A3279
Articles are hosted by Taylor and Francis Online.
An analysis is presented of the integral behavior of the external cooling of a reactor vessel by natural circulation during a severe accident to investigate the feasibility of the in-vessel retention strategy for a high-power reactor by using the RELAP5/MOD3 computer code. It is shown that two-phase flow instability phenomena, including natural-circulation oscillation and density wave oscillations, affect the local thermal margin at the reactor vessel wall. The heat load on the reactor vessel is simplified as a uniform heat flux load of 600 kW/m2 in the base case. A sensitivity study for the effect of the inlet K factor, nonuniform heat flux distribution, inlet flow area, and subcooling of the pool water is performed to evaluate the local thermal margin. The results of the analysis show that natural-circulation cooling is marginal at this level of heat flux. It also clearly indicates that a system level of analysis for two-phase natural circulation, including the sensitivity study on the design parameters, is necessary to ensure successful implementation of the external cooling.
