BIR and BIGR Upgrade Variants for Enlarging Their Interior Cavities

Computational results are presented for the neutron characteristics of BIR and BIGR fast pulse reactors, specifically, cylindrical systems with a core consisting of an alloy of 90% or 36% enrichment uranium with 10 mass% molybdenum or a composite uranium–graphite material. The purpose of the calculations is to determine the possibility of increasing the size of the interior cavities in reactors without appreciably degrading the time parameters of the pulses.