Pebble bed reactor bottom reflector - has peripheral blocks keyed into side reflector to prevent rotation

摘要

A bottom reflector for a nuclear reactor of pebble bed type comprises vertical, horizontally divided hexagonal columns (of graphite blocks) and contains one or more fuel elements discharge zones. A number of the edge columns (46, 48) of this bottom reflector penetrate with projections (50, 52) into corresp. recesses (54, 56) in the inner cylindrical wall face (8) of the side reflector (1). When absorber rods are dropped into the core considerable forces are exerted on the core and transmitted to the bottom reflector; these forces are not necessarily symmetrical and can result in a tendency of the bottom reflector to rotate.