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Ribbon-cutting scheduled for Advanced Manufacturing Collaborative
Energy Secretary Chris Wright will attend the opening of the Advanced Manufacturing Collaborative in Aiken, S.C., on August 7. Wright will deliver remarks and join Savannah River National Laboratory leadership and partners for a ribbon-cutting ceremony.
A. Hébert
Nuclear Science and Engineering | Volume 115 | Number 2 | October 1993 | Pages 177-184
Technical Note | doi.org/10.13182/NSE115-177
Articles are hosted by Taylor and Francis Online.
A practical collision probability model is presented for the description of geometries with many levels of heterogeneity. Regular regions of the macrogeometry are assumed to contain a stochastic mixture of spherical grains or cylindrical tubes. Simple expressions for the collision probabilities in the global geometry are obtained as a function of the collision probabilities in the macro- and microgeometries. This model was successfully implemented in the collision probability kernel of the APOLLO-1, APOLLO-2, and DRAGON lattice codes for the description of a broad range of reactor physics problems. Resonance self-shielding and depletion calculations in the microgeometries are possible because each microregion is explicitly represented.