Series: Nuclear and Reactor Constants

since 1971

Русский (РФ)

ISSN 2414-1038 (online)



Authors & Affiliations

Zhikhareva N.S., Onegin M.S.
Petersburg Nuclear Physics Institute named by B.P. Konstantinov of NRC "Kurchatov Institute", Gatchina, Russia

Zhikhareva N.S. – Senior Assistant.
Onegin M.S. – Senior Researcher. Contacts: 1, mkr. Orlovaroshcha, Gatchina, Leningradskaya Oblast, Russia, 188300. Tel.: +7 (911) 187-95-50; e-mail: This email address is being protected from spambots. You need JavaScript enabled to view it..


The result of calculation of the possibilities of using burnable poison in the PIK research reactor is considered in the article. It is donein relation to the transition from the starting core to the standard. The PIK reactor is a high-flux reactor with a neutron flux in a light-water trap of 4·1015n/cm2sec. The light-water trap is located in the core center and is surrounded by two rows of fuel assemblies with gadolinium and boron burnable poison (twelve hexagonal inner and outer diameters and six tetrahedral outer diameters). The hexagonal fuel assembly contains 241 fuel rods, and the tetrahedral fuel assembly contains 161 fuel rods. In the standard core, the mass of uranium in one fuel rod  has been increased, which leads to an increase in reactivity at the beginning of the reactor life-time, therefore additional burnable poison  are required. Fuel assemblies with gadolinium burnable poison rods and with a different number of rods with a boron burnable poison, a different concentration of boron in the rod and various options for refueling the ½ core are considered. A conservative calculation was performed on the MCNP6 program, in which there was no division in the height of the fuel rods of the core. The most optimal parameters were obtained: the value of the mass fraction of 10B, which is necessary to compensate for excess reactivity at the beginning of the reactor life-time, the number of boron rods in one hexagonal fuel assembly, the option of refueling the ½ core, the length of the equilibrium reactor life-time with refueling and the burn-up depth of 235U and 10B. The article demonstrates that boron burnable poisons can replace cruciform gadolinium burnable poisons in new fuel assemblies of the PIK reactor. Since boron burns out more slowly than gadolinium, this makes it possible to avoid a positive increase in reactivity during the reactor life-time.


PIK reactor, burnable poison, refueling the core, equilibrium reactor life-time, burn-up

Article Text (PDF, in Russian)


UDC 621.039.5

Problems of Atomic Science and Technology. Series: Nuclear and Reactor Constants, 2023, no. 4, 1:7