Abstract: In this parper, the neutronics performance of a solid breeder blanket of a elementary designed fusion-fission hybrid experimental reactor has been studied in one-, two-, three-dimensional analysis and comparison. For being easy to describe the complicated geometry of the Tokamak torus, the neutron and gamma ray coupled transport calculation has been performed with the help of the Monte Carlo code MCNP. For avoiding uncertainties and errors involved in the generation and application of group constants and self-shielding effects, a continuous energy representation of the nuclear data base has been used.The main concern of the study has been the assessment of the spacial distribution of the tritium breeding ratio, the plutonium breeding ratio, and the power density in multi-dimensional configuration and the comparison between One-, two-, three-dimensional global calculation. The role and the limitation of one dimensional calculation has been pointed out.

Key words: hybrid reactor, tokamak torus, neutronics, multidimensional geometry, spacial distribution, power density, plutonium productivity