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Conference Spotlight
2026 ANS Annual Conference
May 31–June 3, 2026
Denver, CO|Sheraton Denver
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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AI at work: Southern Nuclear’s adoption of Copilot agents drives fleet forward
Southern Nuclear is leading the charge in artificial intelligence integration, with employee-developed applications driving efficiencies in maintenance, operations, safety, and performance.
The tools span all roles within the company, with thousands of documented uses throughout the fleet, including improved maintenance efficiency, risk awareness in maintenance activities, and better-informed decision-making. The data-intensive process of preparing for and executing maintenance operations is streamlined by leveraging AI to put the right information at the fingertips for maintenance leaders, planners, schedulers, engineers, and technicians.
S. Patnaik, B. W. Spencer, E. Roberts, T. M. Besmann, T. W. Knight
Nuclear Science and Engineering | Volume 195 | Number 12 | December 2021 | Pages 1307-1326
Technical Paper | doi.org/10.1080/00295639.2021.1932223
Articles are hosted by Taylor and Francis Online.
A variety of normal operation and accident scenarios can generate thermal stresses large enough to cause cracking in ceramic fuel pellets. Cracking in fuel pellets can lead to reduced heat removal, higher centerline temperatures, and localized stress in the cladding—all which impact fuel performance. It is important to experimentally characterize the thermal and mechanical behaviors in the pellet both before and after cracking, which would help to improve cracking models in fuel performance codes such as BISON. However, in-reactor observation and measurement of cracking are very challenging due to the harsh environment and design of the fuel rods involved. Recently, an experimental pellet-cracking test stand was developed for separate-effects testing of pellet cracking under normal operations and accident temperature conditions using thermal imaging to capture the pellet surface temperatures in order to evaluate the thermal stresses and optical imaging to capture the evolution of cracking in real time. Experiments were performed using depleted uranium dioxide (UO2) pellets, which are useful for collecting valuable data for development and validation of cracking models. A combination of induction and resistance heating was used to create thermal gradients similar to those seen in a reactor environment. Characterization of the pellets was conducted both before and after cracking. The cracking patterns are moderately different from those expected in a typical reactor because of the variations in the thermal conditions and pellet microstructures. However, when the actual conditions of these experiments are reproduced in computational models with sufficient precision, such out-of-pile testing on UO2 pellets provides relevant data for modeling purposes.