The main objective of this paper is to summarize multiphysical tasks and methods for their solution in the area of space nuclear power systems being solved and developed by specialists of JSC SSC RF–IPPE. The physical and technical justification of the development and operation of space nuclear power systems with direct conversion of thermal energy into electricity includes an electrothermophysical calculation of characteristics of a thermionic electrical power generating cell and electrical power generating channel as a whole, neutronic physical calculations and structural optimization of the core and radiation shielding.
To determine the electrothermophysical performance of the electrical power generating channel, its 3D detailed computation (software COMSOL-EGK) is used. For the neutronic calculation of the core and radiation shielding characteristics, unified 3D computational software systems are used that implement the Monte Carlo method (in particular, MMKFK-2, MCNP), making it possible to take into account the heterogeneity and all geometry features. The computational procedures and solutions listed in the review are applied in a systematic and integrated manner at JSC SSC RF–IPPE in justification of performance of space nuclear power systems being currently designed.
Key words: thermionic reactor-converter, radiation shielding, electrical power generating channel, MCNP, COMSOL – EGK.