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Nuclear Installations Safety
Devoted specifically to the safety of nuclear installations and the health and safety of the public, this division seeks a better understanding of the role of safety in the design, construction and operation of nuclear installation facilities. The division also promotes engineering and scientific technology advancement associated with the safety of such facilities.
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International Conference on Mathematics and Computational Methods Applied to Nuclear Science and Engineering (M&C 2025)
April 27–30, 2025
Denver, CO|The Westin Denver Downtown
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The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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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.
John P. Church
Nuclear Science and Engineering | Volume 21 | Number 1 | January 1965 | Pages 49-61
Technical Paper | doi.org/10.13182/NSE65-A21015
Articles are hosted by Taylor and Francis Online.
The integral neutron-transport equation is solved for the space-dependent mono-energetic neutron density in a unit cell. By using step functions to represent the spatial dependence of the collision probabilities, one may rearrange the integro-differential transport equation in a special way such that the left-hand side contains only the leakage term and the term describing the total collision probability for the homogeneous medium of one region, k′, of the original problem. The Green's-function technique is then used to convert the integro-differential equation to an integral equation. Thus, although the resulting equation may be applied to a heterogeneous cell, the kernel of the equation depends only on the total collision probability in the particular region k′. Numerical results are presented for a two-region unit cell in slab geometry and compared with published results of DSN, PN double-PN and variational calculations. For unit cells that are of the order of two mean free paths or less in thickness, the zeroth-order spherical harmonic approximation for this method yields results comparable to very high order DSN, PN and double-PN calculations. Further, once the Green's function has been computed, additional cell calculations can be performed with relatively little additional computational effort.