Irradiation campaign in the EOLE critical facility of fiber optic Bragg gratings dedicated to the online temperature measurement in zero power research reactors

Frédéric Mellier (1) , Adriana Morana (2) , Guy Cheymol (3) , Christophe Destouches (1) , Jacques Di Salvo (1) , Sylvain Girard (2) , Guillaume Laffont (4) , Emmanuel Marin (2)

1 CEA-DES (ex-DEN) - CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire)
2 LHC - Laboratoire Hubert Curien
3 SEARS - Service d'études analytiques et de réactivité des surfaces
4 LCFO (CEA, LIST) - Laboratoire Capteurs Fibres Optiques (CEA, LIST)

The control of temperature during operation of zero power research reactors participates to the overall control of experimentation conditions and reveals itself of a major importance more especially when measuring small multiplication factor variations. Within the framework of the refurbishment of the MASURCA facility, the development of a new temperature measurement system based on the optical fiber Bragg grating (FBG) technology is under consideration. In a first step, a series of FBGs is irradiated in the EOLE critical facility with the aim to select the most appropriate. Online temperature measurements are performed during a set of irradiations that should allow reaching a fast neutron fluence nearly 5-1014 n.cm-2 and a total gamma dose less than 4 kGy. The results obtained, especially the Bragg wavelength shifts during the irradiation campaign, are discussed in this paper and compared to data from standard PT100 temperature sensors to highlight possible radiation effects on sensor performances. Work to be conducted during the second step of the project, aiming to a feasibility demonstration using a MASURCA assembly, is also presented.

Mots clés: Fiber gratings; Inductors; Temperature sensors; Uncertainty; Bragg gratings; fibre optic sensors; fission reactor instrumentation; fission research reactors; radiation effects; temperature measurement; EOLE critical facility; online temperature measurement system; zero power research reactor operation; temperature control; multiplication factor variations; MASURCA facility refurbishment; optical fiber Bragg grating technology; fast neutron fluence; total gamma dose; Bragg wavelength shifts; irradiation campaign; standard PT100 temperature sensors; sensor performances; MASURCA assembly

Domaines: Physique Nucléaire Expérimentale [nucl-ex]; Instrumentations et Détecteurs [physics.ins-det]; Thermique [physics.class-ph]; Optique / photonique

Frédéric Mellier, Adriana Morana, Guy Cheymol, Christophe Destouches, Jacques Di Salvo, et al.. Irradiation campaign in the EOLE critical facility of fiber optic Bragg gratings dedicated to the online temperature measurement in zero power research reactors. 2015 4th International Conference on Advancements in Nuclear Instrumentation Measurement Methods and their Applications (ANIMMA), Apr 2015, Lisbon, Portugal. pp.7465570, ⟨10.1109/ANIMMA.2015.7465570⟩. ⟨hal-01889948⟩