Influence of uranium dioxide and reflector surface on neutron yields of the nuclear hybrid fusion-fission reaction using MCUNED code

Abstract

The goal of the present work is to demonstrate the effects of adding uranium dioxide (UO2) to deuterium fuel in the fusion-fission hybrid reactions. The effectiveness of applying a reflector surface on the neutron yield in D-D and D-UO2 reactions has been investigated. The neutrons yielded from the fusion reactions were considered as a neutron source for fission reactions. For this purpose, MCNPX and its extension, the MCUNED code, for D-D fusion processes and UO2 fission reactions were used to calculate the neutron yield and the generated power. Using externally evaluated nuclear data libraries, MCUNED is capable of light ion transport. The D (d, n) 3He reaction with 0.25 gm of deuterium and the fission reactions with 0.25 and 1.0 gm of UO2 were utilized. The results showed that the calculated neutron flux from the D-D fusion reaction increased by a considerable amount when applying the reflector surface. Adding 1.0 gm of UO2 to deuterium fuel enhanced neutron flux by 4.95 times on average, outside the source with the reflector surface. The calculated power increased by about 3-folds when 1.0 gm of UO2 was added. Despite the narrow cross section of the D-D reactions used in this study, it was found that utilizing the reflector surface and UO2 or depleted uranium with restrictive high masses may be able to multiply the generated neutrons and the resulting power.