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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.
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2024 ANS Annual Conference
June 16–19, 2024
Las Vegas, NV|Mandalay Bay Resort and Casino
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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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Commercial nuclear innovation "new space" age
In early 2006, a start-up company launched a small rocket from a tiny island in the Pacific. It exploded, showering the island with debris. A year later, a second launch attempt sent a rocket to space but failed to make orbit, burning up in the atmosphere. Another year brought a third attempt—and a third failure. The following month, in September 2008, the company used the last of its funds to launch a fourth rocket. It reached orbit, making history as the first privately funded liquid-fueled rocket to do so.
Constantine P. Tzanos, Maxim Popov, Fred Mendonca
Nuclear Technology | Volume 173 | Number 3 | March 2011 | Pages 239-250
Technical Paper | One-Phase Fluid Flow | doi.org/10.13182/NT11-A11659
Articles are hosted by Taylor and Francis Online.
To assess the accuracy of large eddy simulation (LES) predictions for a flow in a rod bundle, analyses were performed with different parameters of a constant-coefficient Smagorinsky LES model for a flow in a square-pitch rod bundle, and model predictions are compared with experimental data. The parameters considered are the grid structure, the value of the Smagorinsky constant, the damping of the eddy viscosity, and the size of the channel geometry. Because LES simulations are computationally very demanding, for adequately accurate predictions the grid structure needs to be well optimized in terms of cell size, aspect ratio, and cell orthogonality. The use of hanging nodes can significantly reduce the number of cells without a significant penalty on the accuracy of predictions. For this flow, the change in the value of the Smagorinsky constant from 0.14 to zero did not have a drastic effect on predictions. Although, overall, Lilly damping gave slightly better predictions than van Driest damping, both damping functions gave similar predictions. The LES predictions for the mean axial velocity, for the fluctuating velocity component in the main flow direction, and for the Reynolds stresses are in very good agreement with the experimental measurements. There is also good agreement between predictions and measurements for the wall shear stress, but there is a significant discrepancy between predictions and measurements for the fluctuating velocity components in the lateral directions (u and v).