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Argonne’s METL gears up to test more sodium fast reactor components
Argonne National Laboratory has successfully swapped out an aging cold trap in the sodium test loop called METL (Mechanisms Engineering Test Loop), the Department of Energy announced April 23. The upgrade is the first of its kind in the United States in more than 30 years, according to the DOE, and will help test components and operations for the sodium-cooled fast reactors being developed now.
M. G. Shats, J. H. Harris, J. B. Wilgen, L. R. Baylor, J. D. Bell, C. H. Ma, M. Murakami, T. S. Bigelow, G. L. Bell, R. J. Colchin, R. A. Dory, J. L. Dunlap, G. R. Dyer, A. C. England, G. R. Hanson, D. P. Hutchinson, R. C. Isler, T. C. Jernigan, R. A. Langley, D. K. Lee, J. F. Lyon, A. L. Quails, D. A. Rasmussen, R. K. Richards, M. J. Saltmarsh, J. E. Simpkins, K. L. Vander Sluis, K. M. Likin, K. A Sarksyan, S. C. Aceto, J. J. Zielinski
Fusion Science and Technology | Volume 27 | Number 3 | April 1995 | Pages 481-484
Confinement and Transport Studies | doi.org/10.13182/FST95-A11947133
Articles are hosted by Taylor and Francis Online.
Density fluctuations in low-collisionality, low-beta (β ~ 0.1%), currentless plasmas produced with electron cyclotron heating (ECH) in the Advanced Toroidal Facility (ATF) torsatron have been studied using a 2-mm microwave scattering diagnostic. Pulsed gas puffing is used to produce transient steepening of the density profile from its typically flat shape; this leads to growth in the density fluctuations when the temperature and density gradients both point in the same direction in the confinement region. The wave number spectra of the fluctuations that appear during this perturbation have a maximum at higher k⊥ρ, (~1) than is typically seen in tokamaks. The in-out asymmetry of the fluctuations along the major radius correlates with the distribution of confined trapped particles expected for the ATF magnetic field geometry. During the perturbation, the relative level of the density fluctuations in the confinement region (integrated over normalized minor radii p from 0.5 to 0.85) increases from ñ/n ~ 1% when the density profile is flat to ñ/n ~ 3% when the density profile is steepened. These observations are in qualitative agreement with theoretical expectations for helical dissipative trapped-electron modes (DTEMs), which are drift-wave instabilities associated with particle trapping in the helical stellarator field.