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Applications open for the fall cohort of Mentor Match
Applications are officially open for the second cohort of the American Nuclear Society’s newly redesigned mentoring program. Mentor Match is a unique opportunity available only to ANS members that offers year-round mentorship and networking opportunities to Society members at any point in their education.
The deadline to apply for membership in the fall cohort, which will take place October 1–November 30, is September 17. The application form can be found here.
Carl Sunde, Christophe Demazière, Imre Pázsit
Nuclear Technology | Volume 154 | Number 2 | May 2006 | Pages 129-141
Technical Paper | Fission Reactors | doi.org/10.13182/NT06-1
Articles are hosted by Taylor and Francis Online.
The subject of this paper is the calculation of the in-core neutron noise induced by the shell-mode vibrations of the core barrel. The original motivation was to investigate whether an out-of-phase behavior can exist between the in-core and ex-core (ex-vessel) detectors lying at the same azimuthal position. To this end, a two-region two-group diffusion model was used in one dimension. The noise was calculated by representing the vibrations of the core barrel by a model developed earlier to describe control rod vibrations. It was found that such an out-of-phase behavior indeed exists, although only for in-core detector positions close to the core boundary. This behavior is due to the local component of the noise, which is accounted for in a two-group treatment. The finding is in accordance with the experiment whose result prompted the present work. In addition to its effect on the phase, the local component also manifests itself by a large amplitude of the noise around the vibrating core boundary, i.e., in both the core and the reflector. The appearance and the properties of the local component of the neutron noise for core-barrel vibrations is the main finding of this paper. The results suggest that the efficiency of core-barrel vibrations can be enhanced if in addition to the ex-core detectors, the in-core detectors in the outermost fuel assemblies are used.