FIELD: thermionic plants primarily for space engineering. SUBSTANCE: thermionic conversion reactor has neutron deflector; core assembled of power-generating channels with fuel elements filled with fissionable material. Power-generating channels with fuel elements disposed near deflector are filled with fissionable material based on isotopes having higher neutron breeding factor and are separated from deflector by minimum one layer of power-generating channels with fissionable material of lower breeding factor. Chosen as isotopes of higher neutron breeding factor are 233U, 239Pu., and 241U. isotopes. Chosen as isotope of lower breeding factor is 235U. Proposed design ensures higher reactivity margin of reactor, heat-transfer field equalization throughout reactor core section, equalization of mean temperature of emitter cans over reactor core, and equal operating conditions for thermionic fuel elements. EFFECT: enhanced power characteristics and enlarged service life of reactor. 3 cl, 3 dwg
