ANS is committed to advancing, fostering, and promoting the development and application of nuclear sciences and technologies to benefit society.
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Division Spotlight
Operations & Power
Members focus on the dissemination of knowledge and information in the area of power reactors with particular application to the production of electric power and process heat. The division sponsors meetings on the coverage of applied nuclear science and engineering as related to power plants, non-power reactors, and other nuclear facilities. It encourages and assists with the dissemination of knowledge pertinent to the safe and efficient operation of nuclear facilities through professional staff development, information exchange, and supporting the generation of viable solutions to current issues.
Meeting Spotlight
Utility Working Conference and Vendor Technology Expo (UWC 2022)
August 7–10, 2022
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!
Latest Magazine Issues
Jun 2022
Jan 2022
Latest Journal Issues
Nuclear Science and Engineering
July 2022
Nuclear Technology
Fusion Science and Technology
Latest News
Carbon value: Lifetime extensions of nuclear reactors could save billions in climate mitigation costs
On the road to achieving net-zero by midcentury, low- or no-carbon energy sources that slash carbon dioxide emissions are critical weapons. Nevertheless, the role of nuclear energy—the single largest source of carbon-free electricity—remains uncertain.
Nuclear energy, which provides 20 percent of the electricity in the United States, has been a constant, reliable, carbon-free source for nearly 50 years. But our fleet of nuclear reactors is aging, with more than half of the 92 operating reactors across 29 states at or over 40 years old—the length of the original operating licenses issued to the power plants. While some reactors have been retired prematurely, there are two options for those that remain: retire them or renew their license.
A. Bousbia Salah, J. Vlassenbroeck, H. Austregesilo
Nuclear Technology | Volume 192 | Number 1 | October 2015 | Pages 1-10
Technical Paper | Fission Reactors | dx.doi.org/10.13182/NT14-51
Articles are hosted by Taylor and Francis Online.
Following an accidental event in a nuclear pressurized water reactor, involving the loss of primary-side forced coolant flow, the core decay heat is generally removed through a natural circulation convection process. The cooldown of the reactor coolant system is carried out through the secondary-side heat sink following prescribed guidelines. However, under asymmetric primary-side cooling conditions, natural circulation interruption (NCI) in the loops with an inactive steam generator may take place. Under such conditions, the cooldown of the primary side may be hindered and the transient may evolve toward a degraded state. The NCI issue was recently addressed within the thermal-hydraulic experimental projects ROSA-2 and PKL-2 of the Nuclear Energy Agency of the Organisation for Economic Co-operation and Development. The objective was to identify the conditions that may lead to the occurrence of NCI, to develop cooldown procedures that prevent the occurrence of NCI, and to assess the thermal-hydraulic code capabilities in predicting this phenomenon. In the current study, NCI experimental tests carried out in the LSTF (Large Scale Test Facility) and PKL (Primaer-KreisLauf) facilities are assessed using the best-estimate thermal-hydraulic system codes CATHARE and ATHLET. The simulation results are presented and conclusions are derived accordingly.