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Division Spotlight
Isotopes & Radiation
Members are devoted to applying nuclear science and engineering technologies involving isotopes, radiation applications, and associated equipment in scientific research, development, and industrial processes. Their interests lie primarily in education, industrial uses, biology, medicine, and health physics. Division committees include Analytical Applications of Isotopes and Radiation, Biology and Medicine, Radiation Applications, Radiation Sources and Detection, and Thermal Power Sources.
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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Nuclear Science and Engineering
June 2025
Nuclear Technology
Fusion Science and Technology
May 2025
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.
Frigyes Reisch
Nuclear Technology | Volume 172 | Number 2 | November 2010 | Pages 101-107
Technical Paper | Fission Reactors | doi.org/10.13182/NT10-A10897
Articles are hosted by Taylor and Francis Online.
Some 400 boiling water reactors (BWRs) and pressurized water reactors (PWRs) have been in operation for several decades. The presented concept, the high pressure boiling water reactor (HP-BWR), combines the best parts and omits the troublesome components of traditional BWRs and PWRs by taking into consideration the experiences gained during their operation.One of the major benefits of the HP-BWR is that safety is improved. The design utilizes gravity-operated control rods, and there is a large space for the cross-formed control rods between fuel boxes. The bottom of the reactor vessel is smooth and without penetrations. All the pipe connections to the reactor vessel are well above the top of the reactor core, and core spray is not needed. Additionally, internal circulation pumps are used.The HP-BWR concept is also environmentally friendly: Improved thermal efficiency is achieved by feeding the turbine with [approximately]340°C (15 MPa) steam instead of [approximately]285°C (7 MPa), and there is less warm water release to the recipient and less uranium consumption per produced kWh, resulting in the production of less waste.Finally, the HP-BWR is cost effective and simple, operating in direct cycle mode with no need for complicated steam generators. Moisture separators and steam dryers are placed inside the reactor vessel, and additional separators and dryers can be installed inside or outside the containment. Well-proved simple dry containment or wet containment can be used.In more than half a century, an extensive regulatory licensing experience has been built from traditional BWRs and PWRs. The HP-BWR is a developed, high-performance successor of those conventional designs. Therefore, it can be expected that licensing can be accomplished in a reasonable time.Several utilities are supporting manufacturers to study concepts for future reactors. It is likely that an application to one or more electrical power companies for financial support by a manufacturer to make a detailed feasibility study of the HP-BWR would be positively treated. This could be the next step to the implementation of the HP-BWR.