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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
Argonne’s METL gears up to test more sodium fast reactor components
Argonne National Laboratory has successfully swapped out an aging cold trap in the sodium test loop called METL (Mechanisms Engineering Test Loop), the Department of Energy announced April 23. The upgrade is the first of its kind in the United States in more than 30 years, according to the DOE, and will help test components and operations for the sodium-cooled fast reactors being developed now.
Yang Liu, Shanbin Shi, Yalan Qian, Xiaodong Sun (Univ of Michigan), Nam Dinh (NCSU)
Proceedings | Advances in Thermal Hydraulics 2018 | Orlando, FL, November 11-15, 2018 | Pages 1028-1040
Multiphase computational fluid dynamics (MCFD) is a promising tool to predict fully turbulent gas-liquid two-phase flows with high resolution. As a complex model, extensive validation and uncertainty quantification are required for an M-CFD solver before it can be trusted for large-scale industrial applications. In this paper, the inverse uncertainty quantification based on Bayesian inference is performed to quantify the uncertainty of the turbulence model in STAR-CCM+. As an inverse approach, the Bayesian approach requires experimental measurements to conduct the inference. In this work, high-resolution turbulence data measured by particle image velocimetry are used. The turbulence model with standard wall function and bubble-induced turbulence is considered. Supported by the PIV data, the uncertainties of the coefficients in the model are quantified, based on which the uncertainties of the solver predictions are evaluated. The Bayesian inference is conducted with the Markov Chain Monte Carlo (MCMC) method, based on a surrogate model constructed with Gaussian Process. It is found that the uncertainty of the turbulent kinetic energy is consistent with the measured data. However, it is also found that the liquid velocity is overestimated in the bulk flow region and underestimated in the near wall flow region compared to the measurement data. Such moderate discrepancies between the solver predictions and measurements require a more comprehensive evaluation that takes all relevant closure relations into consideration.