Patent Number: 039430367
Section: claims

1. Fluid-cooled fast breeder reactor comprising an outer cylindrical boundary wall, a plurality of canless fuel elements and breeder material elements received within said boudnary wall and being in an array therein forming a fissionable fuel zone and a breeder material zone coaxially surrounding said fissionable fuel zone, a coolant supply system for applying fluid coolant at uniform pressure to the entire cross section within said cylindrical boundary wall, and flow guide devices extending substantially horizontally and disposed at different levels one above the other within said breeder material zone which coaxially surrounds said fissionable fuel zone, means for elastically securing the flow guide devices at alternate levels within said breeder material elements to said boundary wall, the flow guide devices at the levels intermediate said alternate levels being spaced by an annular gap from said boundary wall. 2. Fast breeder reactor according to claim 1 wherein said flow guide devices are formed of spacer supports, said flow guide devices being disposed in gaps respectively at the levels of said spacer supports for said breeder material elements and the ends of the latter, said spacer support being of such dimension as to fill the gaps between individual breeder material rods forming said elements and the end pieces of said elements to an extent that a limited longitudinal flow of the coolant along said rods is possible. 3. Fast breeder reactor according to claim 1 wherein said flow guide devices are annular in shape and are formed with radially extending heat expansion joints. 4. Fast breeder reactor according to claim 1 including devices for producing turbulent coolant flow disposed in said annular gap. 5. fast breeder reactor according to claim 4 including mounting structures for holding said flow guide devices, said mounting structures being disposed in breeder element positions and extending in axial direction through said breeder material zone. 6. Fast breeder reactor according to claim 1 wherein said flow guide devices are formed of spacer supports for said breeder material elements, said spacer supports being disposed in substantially horizontal planes. 7. Fast breeder reactor according to claim 6 wherein the spacer supports of adjacent breeder material elements abut one another elastically in a sealing manner.