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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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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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Powering the future: How the DOE is fueling nuclear fuel cycle research and development
As global interest in nuclear energy surges, the United States must remain at the forefront of research and development to ensure national energy security, advance nuclear technologies, and promote international cooperation on safety and nonproliferation. A crucial step in achieving this is analyzing how funding and resources are allocated to better understand how to direct future research and development. The Department of Energy has spearheaded this effort by funding hundreds of research projects across the country through the Nuclear Energy University Program (NEUP). This initiative has empowered dozens of universities to collaborate toward a nuclear-friendly future.
Jarod Wilson, Sara Hauptman, Akshay Dave, Kaichao Sun, Lin-wen Hu (MIT), Ruimin Ji, Yang Zou (CAS)
Proceedings | 2018 International Congress on Advances in Nuclear Power Plants (ICAPP 2018) | Charlotte, NC, April 8-11, 2018 | Pages 76-83
The growing global demand for emission-free energy is creating a market for advanced Generation-IV NPP, and the Fluoride salt-cooled High-temperature Reactor design with a pebble-type fuel is a promising candidate. However, this design also brings unique challenges, namely evaluating the effects of the fuel’s distribution and dynamic movement. Generating explicitly described fuel pebble loading patterns is non-trivial. This study serves two main purposes: 1) to investigate the neutronic performance of pebble type fuel within the TMSR-SF1, and 2) to conduct a preliminary comparison between pebble coordinate generation methods. The first method of coordinate generation, the Discrete Element Method (DEM), is a particle-tracking model which accounts for inter-particle forces. While this method generates packing distributions closer to real-world scenarios, it is computationally intense. The alternative method analyzed is a mathematical model (MM), which fills arbitrary domains through simple geometric rules on the addition of particles. This method, while less realistic, generates coordinates significantly faster. Afterwards, fuel pebble coordinates from both methods are utilized to generate inputs for high-fidelity neutronics modelling. The results of these simulations, with the aid of various tools within Python, allowed for the neutronic analysis of the core, specifically when considering the eigenvalues of each coordinate set, and the fission power distribution within the fuel pebbles. It was found that the packing fraction in the axial direction to be consistent within the MM coordinate generation method, and the general trends similar between it and DEM-generated coordinates. Additionally, the eigenvalues of the simulated core were found to be proportional to the number of pebbles within the core. Finally, the fission power distribution of the cores was found to be qualitatively consistent both within many sets of MM-generated coordinates, and in comparisons of the two coordinate generation methods.