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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.
B. Rocca-Volmerange
Nuclear Science and Engineering | Volume 64 | Number 3 | November 1977 | Pages 779-784
Technical Note | doi.org/10.13182/NSE77-A27107
Articles are hosted by Taylor and Francis Online.
This Note expands on a previously communicated synthetic slowing down model to determine the neutron spectra in fast reactors. Based on a polynomial approximation, the model accuracy increases with the order of the expansion. It is, in fact, a generalization to N terms of the one-term classical slowing down models such as those of Fermi, Wigner, and Greuling-Goertzel. Equivalent to the classical and synthetic expression of our QN model, this Note proposes a determination of a “differential” expression of the model, allowing the calculation of a set of functions approximating the kernel Σs(u′ → u). To be used in reactor codes, the spectrum determination has to he associated to a spatial resolution; the second part of this Note is devoted to the adaptation of the QN method to the collision probability approximation or the calculation of a spatial Green's function, to obtain a flux (r,E). The applications in the isotropic collision approximation can be extended to the linearly anisotropic approximation, and various results that demonstrate the validity of the method are given.