Izvestiya vuzov. Yadernaya Energetika

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

Reactor Testing of Experimental Fuel Rods under Design-Basis Loss-Of-Coolant Accident (LOCA) Conditions in the MIR.M1 Reactor Channel

5/18/2026 2026 - #02 Safety, Reliability and Diagnostics of NPI

Izhutov A.L. Dreganov O.I. Kiseleva I.V. Alekseev A.V. Kotov N.P. Sutyagina Ya.A. Poletaev E.I. Markelov A.N.

DOI: https://doi.org/10.26583/npe.2026.2.11

UDC: 621.039.548

The relevance of this study is associated with the necessity to substantiate the safety of reactor facility operation under maximum design-basis loss-of-coolant accidents (LOCA), which represents a key requirement of federal rules and regulations in the field of nuclear energy use. The paper presents a methodology for conducting reactor tests of experimental fuel rods under LOCA conditions in the MIR.M1 research reactor. An experimental procedure and a temperature scenario have been developed to ensure simulation of the second stage of a LOCA, including core dryout and fuel rod depressurization, as well as the third stage corresponding to thermal shock caused by cold water injection. The paper describes design solutions of the irradiation device and a refabricated fuel rod equipped with a differential transformer pressure sensor, which enables real-time monitoring of the internal gas pressure in the fuel rod and the cladding temperature during the experiment. Since 2014, a series of experiments has been carried out on fuel rods with different design features, burnup levels, and fuel compositions. The processes of fuel rod depressurization, cladding ballooning, fuel fragmentation, and fuel relocation have been investigated. The developed methodology ensures safe performance of experiments and prevents contamination of the primary coolant circuit. The obtained experimental data are used to evaluate the thermomechanical state of fuel rods, substantiate the safety of reactor facilities, verify computational codes, and expand the experimental database.

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LOCA MIR.M1 research reactor fuel rod fuel rod depressurization cladding ballooning fuel fragmentation fuel relocation thermal shock cladding temperature gas pressure irradiation device reactor core

Link for citing the article: Izhutov A.L., Dreganov O.I., Kiseleva I.V., Alekseev A.V., Kotov N.P., Sutyagina Ya.A., Poletaev E.I., Markelov A.N. Reactor Testing of Experimental Fuel Rods under Design-Basis Loss-Of-Coolant Accident (LOCA) Conditions in the MIR.M1 Reactor Channel. Izvestiya vuzov. Yadernaya Energetika. 2026, no. 2, pp. 174-189; DOI: https://doi.org/10.26583/npe.2026.2.11 (in Russian).

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