ANS is committed to advancing, fostering, and promoting the development and application of nuclear sciences and technologies to benefit society.
Explore the many uses for nuclear science and its impact on energy, the environment, healthcare, food, and more.
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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Latest News
Zaporizhzhia ‘extremely fragile’ relying on single off-site power line, IAEA warns
Europe’s largest nuclear power plant has just one remaining power line for essential nuclear safety and security functions, compared with its original 10 functional lines before the military conflict with Russia, warned Rafael Mariano Grossi, director general of the International Atomic Energy Agency.
Jang-Guen Park, Sung-Hee Jung, Jong Bum Kim, Jinho Moon, Chan Hyeong Kim
Nuclear Technology | Volume 192 | Number 2 | November 2015 | Pages 133-141
Technical Paper | Thermal Hydraulics | doi.org/10.13182/NT15-16
Articles are hosted by Taylor and Francis Online.
In industrial processes where multiphase flows are frequently encountered, it is important to examine the phase distribution and flow pattern to optimize process efficiency, safe operation, and cost savings. One of the most suitable techniques of industrial-process flow-dynamics visualization is the single photon emission computed tomography (SPECT) system, which provides, by means of a process-system-injected radioisotope source, cross-sectional images of the process flow. Obtaining reliable SPECT imaging results for a multiphase flow system, however, remains a significant challenge. In the present study, the use of a diverging collimator for improvement of industrial SPECT system performance is proposed. The advantages of the diverging-collimation industrial SPECT system as compared with a previous parallel-collimation version can be summarized as follows: (a) significant reduction of edge artifacts on a detection-efficiency map, and 19% improvement of average detection efficiency; (b) 36% improvement of image resolution; (c) accurate source region reconstruction even with the source positioned farther from the object’s center; and (d) a reduced system size.