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Division Spotlight
Reactor Physics
The division's objectives are to promote the advancement of knowledge and understanding of the fundamental physical phenomena characterizing nuclear reactors and other nuclear systems. The division encourages research and disseminates information through meetings and publications. Areas of technical interest include nuclear data, particle interactions and transport, reactor and nuclear systems analysis, methods, design, validation and operating experience and standards. The Wigner Award heads the awards program.
Meeting Spotlight
Utility Working Conference and Vendor Technology Expo (UWC 2024)
August 4–7, 2024
Marco Island, FL|JW Marriott Marco Island
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
Vogtle-3 shuts down for valve issue
One of the new Vogtle units in Georgia was shut down unexpectedly on Monday last week for a valve issue that has since been investigated and repaired. According to multiple local news outlets, Georgia Power reported on July 17 that Unit 3 was back in service.
Southern Company spokesperson Jacob Hawkins confirmed that Vogtle-3 went off line at 9:25 p.m. local time on July 8 “due to lowering water levels in the steam generators caused by a valve issue on one of the three main feedwater pumps.”
G. D. Latimer, W. R. Marcum (Oregon State Univ), W. F. Jones (INL)
Proceedings | Advances in Thermal Hydraulics 2018 | Orlando, FL, November 11-15, 2018 | Pages 777-788
In this study, two pool blowdown experiments were conducted on simulated PWR fuel rods filled with spherical lead pellets as a surrogate fuel having similar density to UO2. These experiments were performed at conditions similar to those expected during the second heatup phase of a loss-of-coolant accident in a conventional light water reactor. The rods were pressurized with a small volume of nitrogen gas at 4.0 MPa to rapidly expel the surrogate fuel particles through a pre-fabricated rupture in the rod. Subsequent dispersion of the particles was captured with a high-speed camera at an acquisition rate of 800 frames per second in order to properly record the transient at a resolved time scale. Initial images revealed contrasting mechanical behavior in the case of a single rod when compared to that in a representative 5x5 section of a fuel bundle. Pressure history on each experiment showed that there is not a significant difference in the depressurization rates of rods with or without the surrogate fuel. Selected particles were tracked in each experiment and overlaid to visualize the differences in the effective range. For the case of the bundle, most of the particles are deposited in the adjacent subchannels, while for the single rod, the mean free path is much longer. Calculated particle displacement and velocity trajectories are compared against theoretical models based on a force balance of a single particle, and show good agreement, with possible errors arising in the transient nature of the drag coefficient, and uncertainties in particle mass.