Method to Study the Release of Fission Gas Products from Fuel Rods

The high-flux research reactor SM was constructed in 1961. This is a vessel-type high-flux reactor with a trap and pressurized water cooling. The reactor design makes it possible to achieve a high flux of thermal neutrons in the moderating trap located in the center of the core with a hard neutron spectrum, the core volume being as small as possible. The priority applications of the SM reactor are energy efficiency, power optimization, and nuclear power engineering. The critical technologies that promote these applications are the physics and engineering of high-flux research reactors, operation and the nuclear fuel cycle of research reactors, and safe management of radioactive waste and spent nuclear fuel. The SM experimental cells and channels are used to irradiate samples of reactor materials under the specified conditions, to study the properties of different materials under irradiation, to produce a wide range of radionuclides, and perform research in the field of nuclear physics. To justify the safe and reliable operation of new fuels, the amount of irradiation-induced fission gas release out of the containment must be measured. In the paper, RIAR’s methodological approach to obtaining data on the activity and nuclide composition of fission gas products when sampling from the sealed region with fuel elements during irradiation is presented.