LOWER SUPPORT OF THE CORE OF A NUCLEAR REACTOR

The lower support of a nuclear reactor core, intended to support each of the combustible assemblies of the core and to distribute the primary cooling fluid through said assemblies. The support is comprised of a first thick plate (7), supporting the combustible assemblies (9) and drilled, facing each assembly (9), with vertical channels (8) intended for the primary fluid flow, and a second thin plate (13), drilled with ports (16), fixed under the first plate (7), and positioned so that each port (16) is located opposite one of the channels (8), each of the channels (8) being open to at least one port (16). Application to nuclear reactors cooled by light water, particularly to those which are used for the production of electric power or for naval propulsion. Support inferieur du coeur d'un reacteur nucleaire, destine a supporter chacun des assemblages combustibles du coeur et a distribuer le fluide primaire de refroidissement au travers de ces assemblages. Le support est constitue d'une premiere plaque (7), epaisse, supportant les assemblages combustibles (9) et percee, au droit de chaque assemblage (9), de canaux verticaux (8) destines au passage du fluide primaire et d'une seconde plaque (13), mince, percee d'orifices (16), fixee sous la premiere plaque (7), et positionnee de facon telle que chaque orifice (16) soit situe au droit de l'un des canaux (8), chacun des canaux (8) etant ouvert sur au moins un orifice (16). Application aux reacteurs nucleaires refroidis a l'eau legere, en particulier a ceux qui sont utilises pour la production d'energie electrique ou la propulsion navale.