Thermal neutron shielding for gas ports - has aerodynamic formed columns of graphite material with high neutron capture cross section material inclusions

摘要

In a core shield for a gas cooled high temp. nuclear reactor, passages are for hot gas flow to boilers and heat exchangers. Graphite pillars are provided, streaching from top to bottom of the passages, to baffle the passages against escape of thermal neutrons. Material for the pillars is graphite with a high thermal neutron capture cross section material embedded in it. The immediate sides of the passages are of graphite blocks with the same embedded material. ADVANTAGE - Considerably less gas flow pressure drop and is simpler and less costly than current solns.