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Division Spotlight
Radiation Protection & Shielding
The Radiation Protection and Shielding Division is developing and promoting radiation protection and shielding aspects of nuclear science and technology — including interaction of nuclear radiation with materials and biological systems, instruments and techniques for the measurement of nuclear radiation fields, and radiation shield design and evaluation.
Meeting Spotlight
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
Standards Program
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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Latest News
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.
Genn Saji, Roy A. Axford
Nuclear Science and Engineering | Volume 35 | Number 3 | March 1969 | Pages 319-331
Technical Paper | doi.org/10.13182/NSE69-A20010
Articles are hosted by Taylor and Francis Online.
A new theoretical formalism of the space-time kinetics is developed for heterogeneous reactor models. The basic time-dependent diffusion equation, which contains terms representing localized absorption and fast-neutron production by fuel rods, has been analytically transformed into a convolution integral form. This enables computation of space- and time-dependent flux for heterogeneous reactors by considering the sizes and spacings of the fuel rods, their geometrical locations, and the nuclear properties of the material used. Although the basic idea and mathematical formalism developed in this paper can be applied for various other space-time kinetics problems, the final calculation is performed for the forced oscillation problem. Two computer codes, HERMITS-1 and HERMITS-2, are developed. By using these codes, it is shown that contour maps of the static flux, phase angles, and amplitudes of neutron waves around the fuel rods can be calculated in an extremely short amount of machine time.