Table of Contents Author Guidelines Submit a Manuscript
Science and Technology of Nuclear Installations
Volume 2015, Article ID 140979, 14 pages
http://dx.doi.org/10.1155/2015/140979
Research Article

Properties of Neutron Noise Induced by Localized Perturbations in an SFR

Institute of Research and Development, Duy Tan University, K7/25 Quang Trung, Da Nang 550000, Vietnam

Received 31 March 2015; Revised 6 June 2015; Accepted 10 June 2015

Academic Editor: Keith E. Holbert

Copyright © 2015 Hoai-Nam Tran. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Investigation of the properties of neutron noise induced by localized perturbations in a sodium-cooled fast reactor has been performed using a multigroup neutron noise simulator. Three representations of the noise source associated with the perturbations of absorption, fission, and scattering cross sections, respectively, were assumed to be located at the first fuel ring around the central assembly. The energy- and space-dependent noise, that is, the amplitude and the phase, was calculated in a wide range of frequencies, for example, 0.1–100 Hz. The results show that in the important energy range (>1.0 keV) where the noise amplitude is significant the phase is almost constant with energy at the calculated frequencies despite the source types. At low frequencies, the variation of the phase is negligibly small at a large distance from the source. The perturbation in several fast groups has a significant contribution and dominates the amplitude and the phase of the induced noise.