New measurement system for on line in core high-energy neutron flux monitoring in materials testing reactor conditions

Research output: Contribution to journalArticle

Authors

  • Benoit Geslot
  • Ludo Vermeeren
  • Philippe Filliatre
  • Anabelle Legrand-Lopez
  • Loic Barbot
  • Christian Jammes
  • Stéphane Breaud
  • Ludovic Oriol
  • Jean-Francois Villard

Documents & links

DOI

Abstract

Flux monitoring is of great interest for experimental studies in material testing reactors. Nowadays, only the thermal neutron flux can be monitored on line, e.g., using fission chambers or self-powered neutron detectors. In the framework of the Joint Instrumentation Laboratory between SCK-CEN and CEA, we have developed a fast neutron detector system (FNDS) capable of measuring on line the local high-energy neutron flux in fission reactor core and reflector locations. FNDS is based on fission chambers measurements in Campbelling mode. The system consists of two detectors, one detector being mainly sensitive to fast neutrons and the other one to thermal neutrons. On line data processing uses the CEA depletion code DARWIN in order to disentangle fast and thermal neutrons components, taking into account the isotopic evolution of the fissile deposit. The first results of FNDS experimental test in the BR2 reactor are presented in this paper. Several fission chambers have been irradiated up to a fluence of about 7 × 1020 n/cm2. A good agreement (less than 10% discrepancy) was observed between FNDS fast flux estimation and reference flux measurement.

Details

Original languageEnglish
Pages (from-to)33504-33510
JournalReview of Scientific Instruments
Volume82
Issue number3
DOIs
Publication statusPublished - 10 Mar 2011

Keywords

  • fast neutron flux, MTR, fission chamber, Campbelling

ID: 72999