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Division Spotlight
Fuel Cycle & Waste Management
Devoted to all aspects of the nuclear fuel cycle including waste management, worldwide. Division specific areas of interest and involvement include uranium conversion and enrichment; fuel fabrication, management (in-core and ex-core) and recycle; transportation; safeguards; high-level, low-level and mixed waste management and disposal; public policy and program management; decontamination and decommissioning environmental restoration; and excess weapons materials disposition.
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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.”
Fausto Franceschini, Bojan Petrovic
Nuclear Technology | Volume 168 | Number 2 | November 2009 | Pages 431-437
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-A9221
Articles are hosted by Taylor and Francis Online.
International Reactor Innovative and Secure (IRIS) is an advanced pressurized water reactor with an integral primary system. It features an integral reactor vessel surrounded by a spherical steel containment 25 m in diameter. Both deterministic and Monte Carlo methods are used to characterize its radiation environment. This paper focuses on the generation of the neutron fission source that is employed as the fixed source in radiation transport calculations. To facilitate radiation shielding analysis, a technique is proposed to synthesize fission source data from the IRIS depletion history into an average and a limiting (maximum) source distribution. The average source preserves the time-integrated, spatially dependent fission neutrons and is suitable for evaluation of long-term irradiation effects, such as the radiation damage on the reactor vessel. The maximum source gives a bounding fission neutron distribution that is suitable for calculation of the maximum instantaneous dose to the personnel. Spatial and spectral effects are also taken into consideration in the source representation. Pinwise axial distributions of the neutron fission source and the associated contribution from primary fissionable isotopes have been generated to allow evaluation of neutron leakage in the critical regions, such as at the core periphery. Less detailed assemblywise axial distributions are also made available to simplify their implementation in the MCNP and TORT models. A comparison of the results obtained with the latter distributions against the reference results (employing the most detailed distribution) will show the impact of simplifications and help identify strategic features and locations where preserving the detailed information is beneficial for meeting specific shielding objectives.The judicious postprocessing and interpretation of the fission source distribution proposed by this approach make the subsequent radiation analysis practical while retaining the critical details needed to achieve high accuracy.