ANS is committed to advancing, fostering, and promoting the development and application of nuclear sciences and technologies to benefit society.
Explore the many uses for nuclear science and its impact on energy, the environment, healthcare, food, and more.
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 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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Nuclear Science and Engineering
August 2024
Nuclear Technology
Fusion Science and Technology
Latest News
Oklo completes end-to-end demonstration of advanced fuel recycling
Oklo Inc. has announced that it has completed the first end-to-end demonstration of its advanced fuel recycling process as part of an ongoing $5 million project in collaboration with Argonne and Idaho National Laboratories. Oklo’s goal: scaling up its fuel recycling capabilities to deploy a commercial-scale recycling facility that would increase advanced reactor fuel supplies and enhance fuel cost effectiveness for its planned sodium fast reactors.
Yassin A. Hassan, Laxminarayan L. Raja
Nuclear Technology | Volume 103 | Number 3 | September 1993 | Pages 310-319
Technical Paper | Nuclear Reactor Safety | doi.org/10.13182/NT93-A34854
Articles are hosted by Taylor and Francis Online.
Loss of residual heat removal during midloop operations was simulated for a typical four-loop pressurized water reactor operated under reduced inventory level using the RELAP5/MOD3 thermal-hydraulic code. Two cases are considered here: one for an intact reactor coolant system with no vents and the other for an open system with a vent in the pressurizer. The presence of air in the reactor coolant system is modeled, and its effect on the transients is calculated. The steam generators are considered under wet layup with water in the secondary covering the U-tubes. The system is pressurized once the water starts boiling in the core. Higher system pressures are seen for the closed-vent case when compared with the open-vent case. Reflux condensation occurs in the steam generator U-tubes preventing complete uncovery of the core and aiding in decay heat removal. The total heat removed by the steam generators is one-third of that produced by the core. The hot leg and vessel upper head pressurization cause the reactor vessel to act as a manometer where the core level drops and the downcomer level rises. This phenomenon is seen at different transient times for the two cases. Since it occurs only for a brief period, the rest of the transient is unaffected. Fuel centerline and clad temperatures are observed to be below the accepted safety limits throughout both transients.