Izvestiya vuzov. Yadernaya Energetika

The peer-reviewed scientific and technology journal. ISSN: 0204-3327

Loop tests of thermionic fuel elements in the AM reactor

12/29/2014 2014 - #04 History of science

Yarygin V.I.

DOI: https://doi.org/10.26583/npe.2014.4.03

UDC: 621.039.566.2(09)

Reactor tests of thermionic fuel elements (TFE) in the loop channels in test reactors have always been and remain an important step in justification of TFE and core design solutions for thermionic reactors (TR) of nuclear power systems (NPS) of various applications. Consideration is given to the results of reactor tests of TFEs inside the loop channels in the core of the World’s First AM Nuclear Power Plant, which in June 2014 celebrates its 60-th anniversary since its commissioning. These results were obtained in the course of over 100 loop tests conducted during the process of designing and development of thermionic reactors under the program of research and development of space NPSs of the first generation, like TOPAZ, AKATSIYA, etc. The principal unresolved problems were stated and recommendations on their solution were given in the studies dedicated to development of space NPSs of the second generation, with the TR extended lifetime and improved value of the output electric power.

The description is given of the AM reactor technological infrastructure that allowed for the TFE loop tests. The profiles of initial and follow-up loop channel and TFE design solutions are considered for various projects of thermionic reactor designs. Special attention is paid to electro-physical and endurance characteristics of tested TFEs with various design solutions for NPSs of the first and second generations.

The analysis of design solutions and reactor test results for multi-element TFEs in NPSs of various applications made it possible to formulate the following principal conclusions: – invaluable experience of development and operation of AM reactor loop installations and the results of over 100 TFE reactor tests in these loops will certainly be used when designing test reactors and TFEs for thermionic NPSs of the second generation and various applications; – there is still an unresolved problem of how to provide a stable and long-life- time output electrical performance of TFEs, with merging the cavities of fuel elements and inter-electrode gaps, for the time period of over a year.


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nuclear reactor thermionic loop channel thermionic fuel element reactor test