Advanced thermionic reactors for surface nuclear power applications Conference Paper uri icon


  • © 1991 by the American Institute of Aeronautics and Astronautics, Inc. A preliminary feasibility study on a new concept for a highly compact space reactor power systems is presented. The considered reactor concept, resulting from a previous trade-off study among various core configurations, consists of in-core thermionic fuel elements and in-core heat pipes for passive core cooling. In arriving at the most desirable configuration, various options have been considered and analyzed, and their advantages/disadvantages have been compared. The reference fuel considered in this study is Uranium Carbide (UC). The calculations reported in this study include a neutronic design analysis using a twodimensional neutron transport model, as well as a simplified one-dimensional thermal analysis of the reactor core, using a preliminary thermal sizing of the in-core heat pipes. Initial results indicate that the proposed core design is thermally and neutronically feasible, with a maximum steady-state fuel temperature below 2000 K. This finding is true when UC fuel is used. Alternate advanced fuels, such as various oxides of 242Am, result in exceedingly high fuel centerline temperatures because of the associated low thermal conductivities. Thus such exotic fuels have not been further considered in this study. Notwithstanding the preliminary nature of the present study, the results which include a new space reactor configuration and its associated technologies indicate promising avenues for the development of highly compact space reactors for use in planetary surface applications with medium power (10 kWe through 100 kWe) needs.

author list (cited authors)


publication date

  • January 1, 1991 11:11 AM