Insertion reliability studies for the RBC-type control rods in ASTRID

M. Zabiego (1) , D. Lorenzo (1) , T. Helfer (1) , E. Guillemin (2)

1 CEA-DES (ex-DEN) - CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire)
2 AREVA

This paper reports on preliminary studies performed regarding the insertion reliability of the RBC-type Control Rods designed for the ASTRID Sodium-cooled Fast Reactor. At this stage, the primary aim of the analysis is to evaluate the mechanical behavior of RBC Control Rods under Emergency Shutdown conditions, for which reactor core structures are subjected to significant misalignments (including earthquakeimposed displacements). Using a Finite Element Model based on the Cast3M solver and developed specifically for these studies, computations are performed that allow assessing contact reactions (and the associated friction forces and contact pressures), deformations and stresses (mostly due to bending-induced deformations) which are considered for design. Based on these preliminary results, some optimization of the Control Rod design is proposed that ensures some stable behavior all along the rod drop, with substantial design margins

Keywords: ASTRID; Control Rod; Insertion Reliability; Mechanical Behavior

Domains: Nuclear Experiment [nucl-ex]; Nuclear Theory [nucl-th]

M. Zabiego, D. Lorenzo, T. Helfer, E. Guillemin. Insertion reliability studies for the RBC-type control rods in ASTRID. International Conference on ast Reactors and Related Fuel Cycles ext Generation Nuclear Systems for Sustainable Development(FR17), Jun 2017, Yekaterinburg, Russia. ⟨cea-02435061⟩