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Thermal Hydraulics
The division provides a forum for focused technical dialogue on thermal hydraulic technology in the nuclear industry. Specifically, this will include heat transfer and fluid mechanics involved in the utilization of nuclear energy. It is intended to attract the highest quality of theoretical and experimental work to ANS, including research on basic phenomena and application to nuclear system design.
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2024 ANS Annual Conference
June 16–19, 2024
Las Vegas, NV|Mandalay Bay Resort and Casino
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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
IAEA issues incident-tracking database fact sheet
Last year, 168 incidents of illegal or unauthorized activities involving nuclear and other radioactive materials were reported to the International Atomic Energy Agency’s Incident and Trafficking Database (ITDB). According to the agency, this number is in line with historical averages. These incidents were reported by 31 IAEA member states; as of 2023, a total of 145 member states have participated in the ITDB.
G. L. Jackson, M. E. Austin, J. S. deGRASSIE, A. W. Hyatt, J. M. Lohr, T. C. Luce, R. Prater, W. P. West
Fusion Science and Technology | Volume 57 | Number 1 | January 2010 | Pages 27-40
Technical Paper | doi.org/10.13182/FST10-A9266
Articles are hosted by Taylor and Francis Online.
Second-harmonic X-mode (X2) electron cyclotron (EC) heating (ECH) has been used in DIII-D in conjunction with plasma initiation and current ramp-up. Although the toroidal inductive electric field E in DIII-D is high enough (0.9 to 1.0 V/m) to allow robust start-up without EC assist, start-up in fusion devices such as ITER will have lower fields (E = 0.3 V/m), and EC assist can provide a reproducible breakdown and an increased margin for burnthrough of low-Z impurities. ECH, applied before the inductive electric field, is used to separate the various phases of plasma breakdown and start-up and is defined as preionization. Preionization first occurs near the X2 resonance location and then expands in the vessel volume. Perpendicular launch (k[parallel] = 0) is found to produce the strongest preionization. The power threshold for preionization can be reduced by optimizing the prefill and the vertical field, although the lowest power threshold is not at the optimum value for ohmic start-up alone. An orbit-following code confirms that cold electrons (0.03 eV) can be sufficiently heated by ECH to energies above the threshold of ionization of hydrogen. This code predicts heating in new tokamaks such as KSTAR and ITER to energies where preionization can occur. The ITER start-up scenario has been simulated in DIII-D experiments, and X2 ECH assist has been applied at reduced toroidal loop voltage to assist burnthrough and plasma current ramp-up.