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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
2025 ANS Annual Conference
June 15–18, 2025
Chicago, IL|Chicago Marriott 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
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Nuclear Technology
Fusion Science and Technology
Latest News
Webinar: MC&A and safety in advanced reactors in focus
Towell
Russell
Prasad
The American Nuclear Society’s Nuclear Nonproliferation Policy Division recently hosted a webinar on updating material control and accounting (MC&A) and security regulations for the evolving field of advanced reactors.
Moderator Shikha Prasad (CEO, Srijan LLC) was joined by two presenters, John Russell and Lester Towell, who looked at how regulations that were historically developed for traditional light water reactors will apply to the next generation of nuclear technology and what changes need to be made.
Sophie Blondel, Karl D. Hammond, Lin Hu, Dimitrios Maroudas, Brian D. Wirth
Fusion Science and Technology | Volume 71 | Number 1 | January 2017 | Pages 22-35
Technical Paper | doi.org/10.13182/FST16-112
Articles are hosted by Taylor and Francis Online.
We provide a description of the dependence on surface crystallographic orientation and temperature of the segregation of helium implanted with energies consistent with low-energy plasma exposure to tungsten surfaces. Here, we describe multiscale modeling results based on a hierarchical approach to scale bridging that incorporates atomistic studies based on a reliable interatomic potential to parameterize a spatially dependent drift-diffusion-reaction cluster-dynamics code. An extensive set of molecular dynamics (MD) simulations has been performed at 933 K and/or 1200 K to determine the probabilities of desorption and modified trap mutation that occurs as small, mobile Hen (1 ≤ n ≤ 7) clusters diffuse from the near-surface region toward surfaces of varying crystallographic orientation due to an elastic interaction force that provides the thermodynamic driving force for surface segregation. These near-surface cluster dynamics have significant effects on the surface morphology, the near-surface defect structures, and the amount of helium retained in the material upon plasma exposure, for which we have developed an extensive MD database of cumulative evolution during high-flux helium implantation at 933 K, which we compare to our properly parameterized cluster-dynamics model. This validated model is then used to evaluate the effects of temperature on helium retention and subsurface helium clustering.