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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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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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
Penn State and Westinghouse make eVinci microreactor plan official
Penn State and Westinghouse Electric Company are working together to site a new research reactor on Penn State’s University Park, Pa., campus: Westinghouse’s eVinci, a HALEU TRISO-fueled sodium heat-pipe reactor. Penn State has announced that it submitted a letter of intent to host and operate an eVinci reactor to the Nuclear Regulatory Commission on February 28 and plans to engage with the NRC on specific siting decisions. Penn State already boasts the Breazeale reactor, which began operating in 1955 as the first licensed research reactor at a university in the United States. At 70, the Breazeale reactor is still in operation.
Jack Chernick
Nuclear Science and Engineering | Volume 1 | Number 2 | May 1956 | Pages 135-155
Technical Paper | doi.org/10.13182/NSE56-A17518
Articles are hosted by Taylor and Francis Online.
The nuclear properties and potentialities of small liquid metal fueled reactors (LMFR) are presented. Plutonium is discussed as an alternate fuel to uranium isotopes, lead as alternate carrier to bismuth, and beryllium as alternate moderator to graphite. Breeding potentialities of U233 and Pu239 fueled liquid metal systems are discussed. It is shown that non-breeder cores can be reduced to about 1 to 4 ft in diameter, depending on fuel concentration and core and reflector compositions. Internal versus external cooling and internal versus external moderation of the small LMFR are compared. Internally moderated reactors have a more complex core but require less fissionable material. For LMFR cores externally moderated by graphite, the critical mass requirements are found to be relatively constant over a wide range of fuel concentrations with a minimum of about 10 kg for U233 fuel. For small LMFR cores, heat transfer rather than heat transport is the only bar to extremely high specific power in power applications and to high neutron flux in research applications. Externally cooled reactors, coupled to conventional heat exchangers require a large external holdup of the liquid metal, thus putting a premium on low fuel concentrations. Internally cooled LMFR's with graphite (or beryllium) moderation and heat exchange require advances in present technology. Sodium is an attractive coolant for an internally cooled, externally moderated version of the LMFR with slurry type fuel elements. It is pointed out that, for research applications, the flux level achievable in a thermal reactor with fixed power output has about reached its practical limit. This is not the situation for intermediate energy reactors. In particular, it is shown that an intermediate energy LMFR can achieve an average core flux of 1015 neutrons/cm2-sec at 10 Mw power output. Finally, integral experiments and neutron cross sections needed for firm estimates of the conversion ratios and critical mass requirements of LMFR systems, especially for weakly moderated systems, are discussed.
