Graphite moderator block - for high temp gas cooled reactor

摘要

Graphite moderator block construction in which a hexagonal configuration with cylindrical fuel channels is used and in which the bottom face of each block is recessed to promote core stability and grooved at the periphery to accept profiled graphite or ceramic sectional seals. The seal profile enables it to adjust to core structural changes induced by thermal or shock loadings and the gas pressure differential between the fuel channels and peripheral interfaces of the stacked blocks constrains the sections to maintain contact with sealing faces and retain primary coolant gas flow within the fuel channels. The formation of channel hot spots is thus inhibited.