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Division Spotlight
Thermal Hydraulics
The division provides a forum for focused technical dialogue on thermal hydraulic technology in the nuclear industry. Specifically, this will include heat transfer and fluid mechanics involved in the utilization of nuclear energy. It is intended to attract the highest quality of theoretical and experimental work to ANS, including research on basic phenomena and application to nuclear system design.
Meeting Spotlight
2024 ANS Annual Conference
June 16–19, 2024
Las Vegas, NV|Mandalay Bay Resort and Casino
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
IAEA calls for action following drone attacks at Ukraine nuclear plant
A recent drone attack at Ukraine’s Zaporizhzhia nuclear power plant prompted an emergency meeting by the International Atomic Energy Agency Board of Governors, during which the agency again called for the immediate removal of Russian military and personnel from the site.
F. Heidet, R. N. Hill
Nuclear Science and Engineering | Volume 187 | Number 2 | August 2017 | Pages 202-211
Technical Paper | doi.org/10.1080/00295639.2017.1312933
Articles are hosted by Taylor and Francis Online.
Given a wide variety of reactor designs and fuel types, it can be difficult to identify the underlying cause of basic performance differences such as flux level and enrichment requirement. In this paper, using solely the definitions of the core multiplication factor and core power, simple relations have been derived allowing estimates of the flux ratio and fissile material concentration ratio for any reactor concept when 235U is replaced with 239Pu or vice versa. These relations are functions of the neutron nonleakage probability, and one only needs to know the number of neutrons emitted per fission and the fission cross-section ratio between the 235U system and the 239Pu system. It is found that for a reactor concept having significant leakage, the achievable flux level when using 239Pu as fissile material can be up to 45% larger than when using 235U as fissile material, and the required fissile concentration of 239Pu is up to 48% lower than that of 235U to achieve criticality.