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Division Spotlight
Robotics & Remote Systems
The Mission of the Robotics and Remote Systems Division is to promote the development and application of immersive simulation, robotics, and remote systems for hazardous environments for the purpose of reducing hazardous exposure to individuals, reducing environmental hazards and reducing the cost of performing work.
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.”
Bojan Petrovic
Nuclear Technology | Volume 168 | Number 2 | November 2009 | Pages 438-443
Shielding | Special Issue on the 11th International Conference on Radiation Shielding and the 15th Topical Meeting of the Radiation Protection and Shielding Division (Part 2) / Radiation Protection | doi.org/10.13182/NT09-A9222
Articles are hosted by Taylor and Francis Online.
The integral configuration of the International Reactor Innovative and Secure (IRIS) with its relatively thick downcomer region within the reactor vessel and compact spherical steel containment offers potential for a significant dose reduction but also presents challenges for the related deep-penetration shielding analyses due to the large spatial domain. It is necessary to determine the radiation field throughout the 25-m-diam spherical containment and into the adjoining auxiliary building.The shielding analysis is being performed using the "traditional" deterministic SN and Monte Carlo approaches and codes (TORT and MCNP, respectively). In the preliminary, scoping phase, the radiation field is sought "everywhere" throughout the power plant to identify any possible shielding issues. This is very challenging for typical Monte Carlo variance-reduction methods, which are devised and may work very well to provide results in a limited region or for individual "detectors" rather than everywhere. However, the recently developed FW-CADIS method, implemented within the MAVRIC sequence of the SCALE code system, aims to address this problem. It uses forward and adjoint deterministic SN calculations to generate effective biasing parameters for Monte Carlo simulations throughout the problem. Previous studies have confirmed its potential for obtaining Monte Carlo solutions with acceptable statistics over large spatial domains.The objective of this work was to evaluate the applicability of FW-CADIS/MAVRIC to efficiently perform the required shielding analysis of IRIS. For that purpose, a representative model was prepared, retaining the main problem characteristics, i.e., a large spatial domain (>10 m in each dimension) and significant attenuation (more than 12 orders of magnitude), but geometrically rather simplified at this stage of evaluation. The obtained preliminary results indicate that the FW-CADIS method implemented through the MAVRIC sequence in SCALE will enable determination of the radiation field throughout the large spatial domain of the IRIS nuclear power plant.