EDN: ESGZAY
Authors & Affiliations
Ivanov A.S., Alekseev P.A.
A.I. Leypunsky Institute of Physics and Power Engineering, Obninsk, Russia/em>
Ivanov A.S. – Research Engineer. Contacts: 1, pl. Bondarenko, Obninsk, Kaluga region, Russia, 249033. Tel.: +7 (484) 399-70-00 (add. 43-88); e-mail: This email address is being protected from spambots. You need JavaScript enabled to view it..
Alekseev P.A. – Senior Researcher, Cand. Sci (Tech.).
Abstract
The article explores the potential for optimizing and balancing energy release in thermionic reactor-converters by employing iron-containing structural materials. These materials are placed on the outer wall of the electrogenerating channel (EGC), in the space between the channel wall and the moderator, enabling effective energy distribution management without altering the internal structure of the reactor. This approach allows the method to be applied without significant modifications to the EGC design. To balance energy release along the height of the EGC, optimizing elements are positioned in the most thermally loaded zones, minimizing thermal overloads and enhancing system stability. For balancing energy release among individual heavily loaded EGCs, iron-containing elements can be installed along the entire height of these channels, ensuring uniform thermal load and extending the reactor’s lifespan. The nuclear power unit with thermionic energy conversion “TOPAZ” is analyzed as an example, alongside a hypothetical large-scale thermionic reactor to assess the scalability of the approach. A key feature of the method is that iron-containing optimization elements are not integrated into the EGC’s internal structure, thus having no impact on the thermionic conversion process or the reactor’s overall functionality. The selected material is a structural steel used in the liquid-metal eutectic coolant (sodium-potassium) circuit, widely applied in thermionic reactors, ensuring compatibility, reliability, and technological continuity. The proposed method enhances the efficiency, safety, and durability of such systems, opening new prospects for their use in space power systems and other high-tech fields requiring stable energy release.
Keywords
thermoelectrophysical characteristics, electrogenerating channel (EGC), thermionic emission, thermionic thermionic reactor-converter, electrogenerating channel, thermionic fuel element, heat generation distribution, power flattening, steel structural elements, reactor temperature reduction
Article Text (PDF, in Russian)
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UDC 621.039.5
Problems of Atomic Science and Technology. Series: Nuclear and Reactor Constants, 2026, no. 2, 2:13
