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Division Spotlight
Human Factors, Instrumentation & Controls
Improving task performance, system reliability, system and personnel safety, efficiency, and effectiveness are the division's main objectives. Its major areas of interest include task design, procedures, training, instrument and control layout and placement, stress control, anthropometrics, psychological input, and motivation.
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.
Jianan Lu, Jiong Guo, Tomasz Kozlowski, Fu Li
Nuclear Science and Engineering | Volume 193 | Number 1 | January-February 2019 | Pages 131-146
Technical Paper – Selected papers from NURETH 2017 | doi.org/10.1080/00295639.2018.1504545
Articles are hosted by Taylor and Francis Online.
The High-Temperature Gas-Cooled Reactor–Pebble Bed Module (HTR-PM) is a large-scale complex system that includes reactor core, steam generator, helium circulator, and other important components. When integrating these components, coupling problems such as multiphysics problem, multicircuit problem, multiscale problem, and multimodule problem arise in the numerical simulation. The HTR-PM multicircuit system comprises the primary circuit and secondary circuit, which are simulated by two independent codes and coupled by the interface in the once-through steam generator. Although time-consuming, Picard iteration is a feasible and convenient coupling method to integrate two components because oversolving in the early stages of the iteration causes strong fluctuation between circuits. To address this problem, optimization of the maximum subiteration number and convergence precision have been implemented to improve the efficiency and numerical stability of the Picard iteration. The Dynamic Residual Balance method, an improved version of the Residual Balance method, is proposed to prevent oversolving inside the subiterations. It takes into consideration fluctuation between circuits, and this method is robust in a wide range of cases. Moreover, the nonlinear preconditioned Jacobian-Free Newton-Krylov method, which has less fluctuation between circuits than Picard iteration, is a coupling scheme that updates all the solution variables from the primary circuit and the secondary circuit simultaneously. Outstanding convergence and efficiency can be obtained by implementing the proper preconditioner in this HTR-PM multicircuit problem. The downside is that it requires significant modification to the legacy codes.