NUCLEAR REACTOR NEUTRONS REFLECTOR Russian patent published in 2009 - IPC G21C5/00 G21C11/06 

FIELD: physics, nuclear physics.

SUBSTANCE: nuclear reactor neutrons reflector contains a tight cover from a structural material, a beryllium block being fitted inside the aforesaid cover and made up of, at least two parts. There is a gap between the block and the cover. The cover thickness is preferably selected subject to the condition of maintaining durability and radiation stability so as to reach the neutrons fluence not less than 7·10²² cm^-2 with energy over 0.8 MeV. The cover material may be represented by a material with neutron absorption low section and high radiation stability at neutrons fluence making at least 7·10²² cm^-2 with energy over 0.8 MeV. Aluminium- or zirconium-based alloys are, mainly, used. The gap between the block and cover preferably makes not less than 0.01 of effective size of the block from beryllium. The reflector can additionally be furnished with spacers representing flexible elements designed to provide a gap between the block and cover. Note that the aforesaid gap can be filled with inert gas, preferably, krypton, xenon or their mix with helium.

EFFECT: longer life of beryllium reflector.

8 cl, 2 dwg