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Aerospace Nuclear Science & Technology
Organized to promote the advancement of knowledge in the use of nuclear science and technologies in the aerospace application. Specialized nuclear-based technologies and applications are needed to advance the state-of-the-art in aerospace design, engineering and operations to explore planetary bodies in our solar system and beyond, plus enhance the safety of air travel, especially high speed air travel. Areas of interest will include but are not limited to the creation of nuclear-based power and propulsion systems, multifunctional materials to protect humans and electronic components from atmospheric, space, and nuclear power system radiation, human factor strategies for the safety and reliable operation of nuclear power and propulsion plants by non-specialized personnel and more.
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2024 ANS Annual Conference
June 16–19, 2024
Las Vegas, NV|Mandalay Bay Resort and Casino
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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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Why should safeguards by design be a global effort?
Jeremy Whitlock
I can’t think of a more exciting time to be working in nuclear, with the diversity of advanced reactor development and increasing global support for nuclear in sustainable energy planning. But we can’t lose sight of the need to plan for efficient international safeguards at the same time.
Global nuclear deployment has been underpinned since 1970 by the Treaty on the Non-Proliferation of Nuclear Weapons (NPT), making it a key customer requirement for governments to demonstrate unequivocally that the technology is not being misused for weapons development.
The International Atomic Energy Agency (IAEA) has helped verify this commitment for more than 50 years, but it has never safeguarded many of the advanced reactors (and related fuel cycle processes) being developed today.
Tamio Kohriyama, Michio Murase, Takashi Nagae, Yukimitsu Okano, Alexandre Ezzidi
Nuclear Technology | Volume 147 | Number 2 | August 2004 | Pages 191-201
Technical Paper | Thermal Hydraulics | doi.org/10.13182/NT04-A3525
Articles are hosted by Taylor and Francis Online.
In a severe accident of a light water reactor (LWR), heat transfer models in a narrow gap between superheated core debris and reactor pressure vessel (RPV) are important for evaluating the integrity of the RPV and emergency procedures. Newly developed heat transfer models are discussed that take into account both the local heat flux on a heated surface, which is characterized by the boiling regime, and the average critical heat flux (CHF) on a heated surface, which is restricted by countercurrent flow limitation (CCFL), including the effect of an inclination angle of the gap. The models were incorporated into the mechanistic detailed code RELAP/SCDAPSIM/MOD3.2. The local heat flux was applied to the outer surface of the debris and the inner surface of the RPV wall. The average CHF was evaluated through the CCFL phenomenon at each junction in the gap. For the assessment, an analysis of Japan Atomic Energy Research Institute's ALPHA test was performed. The calculated peak temperature response of the vessel showed good agreement with the experimental data. It was validated that the new models effectively simulate the coolability in a narrow gap, which could be an effective means of cooling the vessel wall and thereby preventing RPV failure, as was demonstrated in the TMI-2 accident.