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Division Spotlight
Isotopes & Radiation
Members are devoted to applying nuclear science and engineering technologies involving isotopes, radiation applications, and associated equipment in scientific research, development, and industrial processes. Their interests lie primarily in education, industrial uses, biology, medicine, and health physics. Division committees include Analytical Applications of Isotopes and Radiation, Biology and Medicine, Radiation Applications, Radiation Sources and Detection, and Thermal Power Sources.
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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
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.
Jan Bartak, Timo Haapalehto
Nuclear Technology | Volume 106 | Number 1 | April 1994 | Pages 46-59
Technical Paper | Nuclear Reactor Safety | doi.org/10.13182/NT94-A34949
Articles are hosted by Taylor and Francis Online.
A top-down reflooding model was developed and implemented into the French best-estimate thermalhydraulic code CATHARE2 V1.3E. A two-dimensional mesh moving along the wall with the quench front is used to resolve the heat conduction equation in the wall near the quench front. The results of the model validation and the first assessment calculations are given. The Winfrith single-tube top-down reflooding experiments were used to validate the model. The influence of wall material, pressure, mass flux, and wall temperature on the quench front velocity are correctly predicted. The REWET-II and PERICLES experiments in rod bundle geometry were used to assess the capabilities of the code to predict simultaneous bottom and topdown rewetting. Comparison of the calculated results with the RE WET II experimental data shows the ability of the new package to calculate the key features of this complex experiment. The existence and progression of two quench fronts in the core are correctly predicted. The maximum cladding temperatures are overpredicted for experiments with combined and upper plenum injection. This difference, which is attributed to a too severe countercurrent flow limit (CCFL) calculated by the code, does not exceed 150°C. With the top-down reflooding option, improved predictions of wall temperatures in the upper part of the core in the PERICLES tests with respect to the previous version of the code were obtained, since this part of the core was rewetted by top-down quenching. To realize further improvements in combined reflooding calculations, the CCFL predicting capabilities of CATHARE should be addressed first. More detailed experimental information and additional data would also be required for in-depth assessment of the models.