FIELD: nuclear power engineering and space engineering; space-based nuclear power plants. SUBSTANCE: thermionic conversion power reactor has power generating stacks in the form of pressurized vessel provided with coolant inlet and outlet pipes disposed at one of its ends; this vessel accommodates cooled thermionic powergenerating fuel assemblies, coolant dispensing and accumulating headers disposed at two ends of power-generating stacks; connected to accumulating header is coolant outlet pipe wherein at least one coolant feed pipe is installed inside each stack coaxially to power-generating fuel assemblies; one end of this pipe is hydraulically joined with coolant inlet pipe and other end is hydraulically connected to coolant dispensing header. All power- generating fuel assemblies operate under approximately same coolant temperature conditions. EFFECT: enhanced power generation efficiency, reduced space requirement, facilitated assembly, reduced heat transfer from one part of core to other. 1 cl, 3 dwg
