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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.
Ezio Bittoni, Marcel Haegi
Fusion Science and Technology | Volume 22 | Number 4 | December 1992 | Pages 461-469
Alpha-Particle Special | doi.org/10.13182/FST92-A30081
Articles are hosted by Taylor and Francis Online.
The diffusion coefficient for the fast alpha particles produced in a thermonuclear plasma is derived numerically for the case of a magnetic field perturbed by ripple and magnetohydrodynamic (MHD) helical modes. It is found that this diffusion coefficient varies monotonously with the amplitude of the magnetic perturbations and that the transition from the classic to the stochastic regime occurs smoothly. The ripple perturbations as well as the MHD perturbations essentially affect the trapped-particle orbits. It is shown that above an MHD perturbation amplitude of some 10−3 of the total magnetic field, severe fast alpha-particle losses must be expected. Parametric studies have shown the dependence of the MHD helical diffusion coefficient on the amplitude of the perturbation, the helical mode number, and the energy of the alpha particles. An analytic expression for the MHD diffusion coefficient, based on these scalings, is proposed.