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

since 1971

Русский (РФ)

ISSN 2414-1038 (online)

GENERALIZED RESULTS  OF THE EXPERIMENTAL STUDIES ON HEAT EXCHANGE IN FUEL SUBASSEMBLIES OF FAST REACTORS

EDN: YRPRRO

Authors & Affiliations

Sorokin A.P.1, Sorokin G.A.2, Kuzina Yu.A.1, Denisova N.A.1
1 A.I. Leypunsky Institute for Physics and Power Engineering, Obninsk, Russia
2 Moscow Institute of Physics and Technology, Moscow, Russia

Sorokin A.P.1 – Chief Researcher, Dr. Sci. (Tech.). Contacts: 1, pl. Bondarenko, Obninsk, Kaluga region, Russia, 249033. Tel.: +7 (484) 399-70-00 (add. 84-47); e-mail: This email address is being protected from spambots. You need JavaScript enabled to view it..
Kuzina Yu.A.1 – Head of Department of Nuclear Power Engineering, Cand. Sci. (Tech.).
Denisova N.A.1 – Lead Engineer.
Sorokin G.A.2 – Associate Professor, Cand. Sci. (Tech.).

Abstract

Modern requirements for justification of operability of elements of the fast reactors core require determination of not only the level of maximum temperature of the fuel rod cladding, but also significantly greater detail in the temperature distribution along their perimeter, as well as the temperature distribution of the fuel assembly jacket. The article presents the methods of modeling heat exchange processes developed at IPPE JSC, developed sensors and measurement equipment directly on models in channels and fuel rod assemblies of fast reactors with alkaline liquid metal coolants. The results of experimental studies on test facilities with liquid metal coolants of heat exchange and temperature fields for laminar and turbulent flow regimes for a wide range of geometric parameters and flow characteristics of fuel rod assemblies of fast reactors are presented and analyzed. The article presents the results of studies of the influence of various factors on heat exchange and temperature fields of fuel elements for nominal and non-nominal conditions, including the operating conditions of the reactor during a campaign: the influence of the features of the geometry of the peripheral region of fuel assemblies, deformation of the fuel element lattice and fuel assembly jackets with deviation of geometric parameters (tolerances for manufacturing and placement of fuel elements, displacement, deflection, radiation swelling), non-uniformity of neutron flux (energy release), heat exchange through the fuel assembly jacket to coolant leakage in the gaps between fuel elements, various types of spacing of fuel elements, including multidirectional windings on fuel elements, etc. The effect of equalization of temperature fields in the cross-section of the fuel assembly due to interchannel heat and mass transfer is demonstrated. The dependences for coolant temperature distributions in the cross-section of the fuel assembly, heat transfer and azimuthal non-uniformity of the fuel element temperature under various geometric conditions and operating parameters obtained as a result of generalization of experimental data are presented. The degree of influence of various factors on the temperature regime in fuel rod assemblies is demonstrated. The presented data can be used both to justify the temperature regimes of fast reactor core and to verify thermal hydraulic calculation codes that take into account the influence of random (stochastic) and regular deviations of parameters on the temperature regime.

Keywords
fast reactors, liquid metals, experiment, heat exchange, reactor core, fuel assemblies, energy release, geometric, regime, technological factors, distribution of parameters, campaign, deformation, radiation effects, temperature, heating of coolant

Article Text (PDF, in Russian)

References

UDC 536.24:621.039.524.4:621.039.584

Problems of Atomic Science and Technology. Series: Nuclear and Reactor Constants, 2026, no. 1, 1:15