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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
International Conference on Mathematics and Computational Methods Applied to Nuclear Science and Engineering (M&C 2025)
April 27–30, 2025
Denver, CO|The Westin Denver 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
TerraPower begins U.K. regulatory approval process
Seattle-based TerraPower signaled its interest this week in building its Natrium small modular reactor in the United Kingdom, the company announced.
TerraPower sent a letter to the U.K.’s Department for Energy Security and Net Zero, formally establishing its intention to enter the U.K. generic design assessment (GDA) process. This is TerraPower’s first step in deployment of its Natrium technology—a 345-MW sodium fast reactor coupled with a molten salt energy storage unit—on the international stage.
Chien-Hsiung Lee, I-Ming Huang, Chin-Jang Chang, Tay-Jian Liu, Yuh-Ming Ferng
Nuclear Technology | Volume 126 | Number 1 | April 1999 | Pages 48-61
Technical Paper | Thermal Hydraulics | doi.org/10.13182/NT99-A2957
Articles are hosted by Taylor and Francis Online.
The RELAP5/MOD3.2 code is used at the Institute of Nuclear Energy Research Integral System Test Facility to analyze a 2% cold-leg-break experiment that includes failure of the high-pressure injection system. The assessment code predictions include primary pressure, inventory distribution in the reactor coolant system (RCS), loop flow rate, break flow rate, and core thermal hydraulics. A comparison between the calculated results and the experimental data shows (a) a good match with the predictions of the RCS pressure and hot- and cold-leg fluid temperatures, (b) underprediction of the core and downcomer levels, (c) overprediction of the loop flow rates in single- and two-phase natural circulation, and (d) inadequate prediction of asymmetric coolant holdup in the three steam generators. Also presented are sensitivity studies of choked flow associated with the defaulted values of discharge coefficients in the simulation of the break flow, and of the core bypass area to evaluate the effect of core level depression.