Reactivity monitoring of the accelerator driven VENUS-F subcritical reactor with the "current-to-flux" method. (June 2019)

• Record Type: Journal Article
• Authors: Marie, N.; Lecouey, J.L.; Lehaut, G.; Chevret, T.; Billebaud, A.; Chabod, S.; Doligez, X.; Kochetkov, A.; Krása, A.; Lecolley, F.R.; Mellier, F.; Uyttenhove, W.; Vittiglio, G.; Wagemans, J.
• Is Part Of: Annals of nuclear energy. Volume 128(2019)
• Page Start: 12
• Page End: 23
• Publication Date: 2019-06
• Subjects: Reactivity monitoring -- Current-to-flux -- Subcritical -- ADS -- MCNP simulations; Nuclear energy -- Periodicals; Nuclear engineering -- Periodicals; 621.4805
• DOI: 10.1016/j.anucene.2018.12.033
• Languages: English
• ISSNs: 0306-4549

Abstract

Highlights: The "current-to flux" method for monitoring ADS subcriticality was successfully tested experimentally. Spatial effects affecting the reactivity estimation can be corrected with Monte Carlo simulations. The robustness and precision of the correction technique is demonstrated. Abstract: In this article, we evaluate the quality and robustness of a method envisaged for the on-line monitoring of the subcriticality of an ADS, called the "current-to flux" (CTF) method. For this evaluation, we performed a dedicated experiment at the GUINEVERE facility. It is hosted at the SCK-CEN and consists of the subcritical VENUS-F reactor coupled to a continuous external neutron source provided by the GENEPI-3C accelerator. During this experiment, the reactor control rods were moved in various patterns, and the subsequent dynamical evolutions of the reactor reactivity were monitored using nine fission chambers (FCs). The space-energy effects that bias the reactivity values are corrected using a procedure based on simulations computed with the Monte Carlo neutron transport code MCNP. We investigate the precision of this correction procedure by comparison with a reactivity value extracted with the beam interruption technique and we demonstrate its insensitivity to the simplifications made on the VENUS-F reactor modeling and to a simulation key parameter such as the boron carbide density filling the control rods.