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Nuclear Criticality Safety
NCSD provides communication among nuclear criticality safety professionals through the development of standards, the evolution of training methods and materials, the presentation of technical data and procedures, and the creation of specialty publications. In these ways, the division furthers the exchange of technical information on nuclear criticality safety with the ultimate goal of promoting the safe handling of fissionable materials outside reactors.
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Conference on Nuclear Training and Education: A Biennial International Forum (CONTE 2025)
February 3–6, 2025
Amelia Island, FL|Omni Amelia Island Resort
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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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ANS standard updated for determining meteorological information at nuclear facilities
Following approval in October from the American National Standards Institute, ANSI/ANS-3.11-2024, Determining Meteorological Information at Nuclear Facilities, was published in late November. This standard provides criteria for gathering, assembling, processing, storing, and disseminating meteorological information at commercial nuclear power plants, U.S. Department of Energy/National Nuclear Security Administration nuclear facilities, and other national or international nuclear facilities.
I. Pázsit, A. Jonsson
Nuclear Science and Engineering | Volume 167 | Number 1 | January 2011 | Pages 61-76
Technical Paper | doi.org/10.13182/NSE10-15
Articles are hosted by Taylor and Francis Online.
The dynamic space- and frequency-dependent response of a molten salt reactor (MSR) to stationary perturbations is investigated in a simple analytical model. The Green's function of the system is investigated in the general case of arbitrary fuel recirculation velocity and in the limiting case of infinite fuel velocity, which permits closed-form solutions in both the static and dynamic cases. It is found that the amplitude of the induced noise is generally higher and the domain of the point kinetic behavior valid up to higher frequencies than in a corresponding traditional system. This is due to the differing behavior of the delayed neutron precursors as compared to the traditional case. The MSR equations are not self-adjoint and the adjoint equation and adjoint function have to be constructed, which is also done here. Finally, the space-dependent neutron noise, induced by propagating perturbations of the absorption cross section, is calculated. A number of interesting properties that are relevant to full-size MSRs are found and interpreted. The results are consistent with those in traditional systems, but the domains of various behavior regimes (point kinetic, space dependent, etc.) are shifted to higher frequencies or system sizes.