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Denver, CO|The Westin Denver Downtown
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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.
S. P. Congdon, M. R. Mendelson
Nuclear Science and Engineering | Volume 33 | Number 2 | August 1968 | Pages 151-161
Technical Paper | doi.org/10.13182/NSE68-A20653
Articles are hosted by Taylor and Francis Online.
The derivation of blackness boundary conditions is reviewed and generalized into a standard matrix formalism that is valid for any order PN approximation. It is then shown that for a finite slab effective diffusion and absorption matrices can be found which reproduce blackness boundary conditions at the interfaces. In the continuous or infinitely many mesh point description of the black region, the analysis leads to infinite series expressions for the equivalent matrices, which have been evaluated explicitly by means of the Caley-Hamilton theorem for the case of the P 3 approximation. Equivalent matrices have also been derived for two- and three-mesh-point descriptions of the black region. Numerical calculations for three model problems indicate that P3 blackness theory is a great improvement over conventional P3 theory and is roughly equivalent to P5 theory in the prediction of both the exterior scalar flux and the absorption rate in the black region.