Water displacer rod for use in a spectral shift nuclear reactor.

摘要

The invention relates to an improved water displacer rod for use in a nuclear fuel assembly.
<??>The rod (30) comprises a relatively thin-walled tube (36) sealed at both ends thereof and containing a stack of substantially cylindrical pellets (34) each of which is hollow and defines an inner void (48) individually sealed from the inner voids of adjacent pellets.
<??>The pellets with the sealed voids therein increase the collapse-resistance of the thin-walled tube without destroying its lateral flexibility or unduly increasing its mass, and they also prevent reactor coolant from flooding the tube in the event rupture thereof occurs.