PROBLEMS OF ATOMIC SCIENCE AND TECHNOLOGY
Series: Nuclear and Reactor Constants

since 1971

Русский (РФ)

ISSN 2414-1038 (online)

RESEARCH OF THE EFFECT OF ISOTOPIC COMPOSITION OF FUEL ON NEUTRON-PHYSICAL CHARACTERISTICS RP BR-1200

EDN: EUZJNE

Authors & Affiliations

Zhirnov A.P., Davydov V.K., Moiseev A.V., Soldatov E.O., Khakhulin V.I.
N.A. Dollezhal Research and Development Institute of Power Engineering, Moscow, Russia

Zhirnov A.P. – Head of Department.
Davydov V.K. – Senior Researcher.
Moiseev A.V. – Scientific Supervisor of the BREST-OD-300 Project, Cand. Sci. (Phys.-Math.).
Soldatov E.O. – Head of Group. 1, bld.3, pl. Akademika Dollezhalya, Moscow, Russia, 107140. Tel.: +7 (499) 763-04-57; e-mail: This email address is being protected from spambots. You need JavaScript enabled to view it..
Khakhulin V.I. – Engineer of the 2nd Category.

Abstract

The paper considers fuel composition options using the BR-1200, BN-1200M starting load, the BN-800 blanket, the VVER MOX spent nuclear fuel and the VVER spent nuclear fuel plutonium to confirm the operation of the reactor in an equilibrium mode with a low reactivity margin. Calculations and research of the effect on the neutron-physical characteristics of the reactor by the considered fuel compositions were performed. The fuel density and the mass fraction of plutonium are adjusted when the isotopic composition of plutonium changes. The calculations of the neutron-physical characteristics and campaign at the initial stage of the BR-1200 reactor operation were carried out using the MCU-BR and FACT-BR programs. Changing isotopic composition of BR-1200 plutonium to isotopic compositions of other variants leads to redistribution of absorption and fission rates among plutonium isotopes. Since the reactivity weights of isotopes 238Pu, 239Pu, 240Pu, 241Pu, 242Pu have different values, the course of reactivity in the campaign differs for different variants of the isotopic composition of plutonium. As part of the simulation of the reactor campaign with the researched fuel compositions, the fuel assembly reload scheme was determined at the initial stage of operation. The fuel density and the mass fraction of plutonium in the loaded fuel were selected to ensure a reactivity margin within 1 βeff and the order of permutation and replacement of permanent reactivity control absorbers was determined. The research was conducted on the dependence of reactivity margin on fuel storage duration. It was concluded that for the isotopic composition from the BN-1200M, the VVER MOX spent nuclear fuel and the VVER spent nuclear fuel it is necessary to adhere to the panned dates for the reactor start-up and reactor commissioning. For the initial core load of the BR-1200 and the BN-800 blanket the reactivity margin can be maintained within 1 βeff by using permanent reactivity control absorbers.

Keywords
BR-1200 reactor, neutron-physical calculation, lead coolant, isotopic composition of plutonium, fast reactor fuel

Article Text (PDF, in Russian)

References

UDC 621.039.51

Problems of Atomic Science and Technology. Series: Nuclear and Reactor Constants, 2026, no. 1, 1:7