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Nuclear Installations Safety
Devoted specifically to the safety of nuclear installations and the health and safety of the public, this division seeks a better understanding of the role of safety in the design, construction and operation of nuclear installation facilities. The division also promotes engineering and scientific technology advancement associated with the safety of such facilities.
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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
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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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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.
Florin Curca-Tivig
Nuclear Technology | Volume 124 | Number 1 | October 1998 | Pages 65-81
Technical Paper | Thermal Hydraulics | doi.org/10.13182/NT98-A2909
Articles are hosted by Taylor and Francis Online.
The European Pressurized Water Reactor's (EPR's) safety injection system (SIS) comprises four trains, each of them consisting of a medium head safety injection, an accumulator, and a low head safety injection (LHSI). Injection mode is into the cold legs of the main coolant line for the short term. This emergency core cooling (ECC) mode is quite different from the typical German concept with combined injection, i.e., safety injection into both the cold and the hot legs of the main coolant line at least for accumulator and LHSI. Therefore, the German Safety Authority requested justification for giving up the ECC-mode used in German pressurized water reactors, the so-called "combined injection." Furthermore, the Reaktor-sicherheitskommission requested a comparison between cold-leg injection and combined injection in terms of ECC efficiency over all relevant accident sequences.The evolution from combined injection to cold-leg injection is described and results of comparative analysis are summarized. It is demonstrated that EPR's SIS is a well-balanced system, which ensures high ECC efficiency and limits loads to containment over the whole accident spectrum. For the entire loss-of-coolant accident (LOCA) spectrum, ECC efficiency of EPR's SIS is practically equivalent to ECC efficiency of a SIS of the KONVOI type with combined injection. The smaller the break, the more insignificant are differences. The ECC mode has a negligible impact on containment pressure and temperature evolution during a LOCA. Neither with combined injection nor with cold-leg injection is a containment spray system needed.
