Reactor core, used in light water reactors contains, number of fuel elements with fuel rods with cladding tubes surrounding nuclear fuel column containing combustible neutron absorber with enriched gadolinium

摘要

Reactor core contains a number of fuel elements during a first operating cycle, each element containing a number of fuel rods. Each rod contains a cladding tube which surrounds a column made of nuclear fuel. The fuel contains a combustible neutron absorber. The absorber contains enriched gadolinium at the beginning of the first operating cycle. The gadolinium is enriched with one or more isotopes which have a larger neutron absorption cross-section than naturally occurring gadolinium.