Status of GFR pre-conceptual design study

The revision of the GFR (Gas cooled Fast Reactor) core design (plate type with a honeycomb SiC structure containing separated uranium/plutonium fuel pellets) is underway. The self-breeding searched for is achieved with an optimized core design called 12/06-E. The S/A fuel is divided into 3 zones: the upstream zone, the fissile zone and the downstream zone. The fissile zone is made of 24 fuel plates separated by helium channels. The core coolability in natural circulation for pressurized conditions has been studied. The design and safety criteria are met but no margin remains. Fluid dynamics calculations confirms the maximum pressure drop in the central S/A. Finally, the new core design is considered as acceptable from the thermal-hydraulics point of view. The project is now addressing the feasibility and the design of the S/A fuel. (authors)