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Decommissioning & Environmental Sciences
The mission of the Decommissioning and Environmental Sciences (DES) Division is to promote the development and use of those skills and technologies associated with the use of nuclear energy and the optimal management and stewardship of the environment, sustainable development, decommissioning, remediation, reutilization, and long-term surveillance and maintenance of nuclear-related installations, and sites. The target audience for this effort is the membership of the Division, the Society, and the public at large.
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.
Mariano Tarantino, Pierdomenico Lorusso, Alessio Pesetti, Ivan Di Piazza, Daniele Martelli
Nuclear Technology | Volume 210 | Number 4 | April 2024 | Pages 725-739
Research Article | doi.org/10.1080/00295450.2023.2226525
Articles are hosted by Taylor and Francis Online.
Since the 2000s, the development of Generation-IV fast reactors cooled by heavy liquid metals (HLMs) has been pursued by several research activities and projects, many of which are co-funded by the European Commission. One of the key points of HLMs regards their good neutronic and thermophysical properties, allowing for the of design cores with a high pitch-to-diameter ratio. In terms of passive safety, with a properly designed configuration, it is possible to increase the system capability to remove the decay power in a natural circulation regime, reducing active safety systems involvement. Such a safety-related aspect has been experimentally investigated at the ENEA Brasimone Research Center within the European Union co-funded Euratom H2020 SESAME project.
An experimental campaign reproducing protected loss-of-flow accident (PLOFA) scenarios has been executed on CIRCE, a lead-bismuth eutectic-cooled pool-type facility reproducing in relevant scale the main components of HLM-cooled fast reactors. A test section named HERO has been installed in the CIRCE main vessel, hosting a double-wall bayonet tube steam generator scaled 1:1 in length with respect to the one envisioned for the ALFRED reactor. The tests reproduce the loss of primary coolant flow, while the power supplied by the heating source decreases according to a characteristic decay heat curve. The feedwater in the secondary system is regulated to operate the main steam generator as a decay heat removal (DHR) system.
This paper presents the PLOFA transient reproducing the worst case, where the steam generator feedwater is suddenly stopped, simulating the full loss of the heat sink (no DHR). The main phenomena occurring during the transition from forced to natural circulation are presented and discussed. The experiment shows that, despite the loss of the forced circulation regime in the primary loop and the full loss of the heat sink, the entire system is still capable of operating safely, assuring an effective long-term cooling, as long as the thermal heat losses from the main vessel balance the decay power supplied by the heating source.
